The Unicrown Fork

Those who have been reading this blog for some time, are no doubt familiar with my rants against unicrown forks. "The bike is nice... if it weren't for that unicrown fork," and so forth. When the topic comes up, some agree, others question my fixation on this detail, and others still want to know what a unicrown fork is. Now that I am temporarily living with a unicrown forked bike, the time seems right to elaborate.

A vey basic primer in bicycle fork construction: A traditional fork on a traditional lugged steel bike is made up of two blades and a crown, whereby the blades and crown are brazed together - just like the tubes and lugs on the frame itself. There are many fork crown designs in existence, but the general concept is the same. Now, a unicrown fork is constructed differently in that there is no crown. The two fork blades are bent towards each other at the top, then (typically) welded together at the steerer tube. A unicrown fork is simpler and less expensive to make than a lugged crown fork, which is why it has become so ubiquitous among contemporary bicycle manufacturers.

For some time now I've been trying to figure out the history of the unicrown fork, and I keep reading about the first mountain bikes, BMX bikes, and the quest for rigidity - suggesting that its origins were in the 1980s. But then I see antique bicycles  - like this ancient Sterling pathracer at the Larz Anderson show last summer - which to me look like they are sporting hundred year old versions of unicrown forks. I have also seen what I can only describe as antique crownless flat-top forks - which appear to be similarly constructed, but are squared-off, rather than round. Would someone care to educate me on their history?

The thing about unicrown forks, is that I don't actually dislike them per se, at least not in of themselves. What I dislike is when they are incongruent to the overall design of the bicycle. On a welded frame, a unicrown fork looks perfectly natural - integrating harmoniously with the bicycle frame. Just like I prefer lugged frames to welded frames, I similarly prefer lugged forks to unicrown forks. But objectively speaking, a unicrown fork looks fine on a welded frame - like on the D2R Boogie above.

Unicrown fork on a welded DBC Swift, also looks appropriate.  The frame joints and the unicrown fork match, and all are filed equally smoothly. 

Unicrown fork on an ANT mixte. Now, if I were getting an ANT, I would opt for his segmented fork or his dual-plate crown fork - just because I prefer those styles and they are kind of his specialties. But I don't think there is anything inherently wrong with ANT using unicrown forks on TIG-welded bikes - again, the overall design is harmonious.

The only time a unicrown fork actually bothers me, is when it is attached to a lugged frame - which is done quite frequently nowadays. Azor/Workcycles puts unicrown forks on their lugged frames, as do Batavus, Velorbis (balloon tire models only) and Abici (above), just to name a few. The reason is most likely a cost-cutting measure, undertaken perhaps with the hope that most customers simply won't notice. And it bothers me, not because I think that unicrown forks in themselves are "bad," but because I feel that a traditional lugged bicycle - especially when the manufacturer takes pride in describing it as such - calls for a traditional lugged fork. When the frame is lugged but the fork is not, the overall look of the bike comes across as disjointed to me; it doesn't "flow." It's only my opinion, but I think it's a fairly simple and logical notion as far as design goes.

Do you care what kind of fork your bicycle has? What do you think of unicrown forks - in of themselves, and in combination with lugged frames?

Comments

  1. I agree. Apart from everything else that bugs me about my bike (the shortish top tube, the shortish chainstay, the lack of rack mounts) the unicrown fork on an OK lugged frame is annoying. I think it also contributes to lack of tyre space up front.
    Matt K

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  2. Unicrowns with lugs are just *wrong*. They look like the fork is an after-thought, not an essential part of the design. My Tig-welded LHT has a unicrown, and it looks right - but the fork was designed with the rest of the bike. My lugged and beloved RB-2 has a lugged fork...and again, the design just flows. Nevermind that GP designed the bike, so I would expect nothing less. I think that's the real key - was the fork an afterthought? A cost-cutting measure?
    Does it make engineering and aesthetic sense? A yes to the first two questions and thumbs down. A yes to the second two - a probable thumbs up.

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  3. i have a problem with them on almost all bikes, lugged or otherwise.. for example, the bianchi pista is ruined by the fork.

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  4. Anon 1:04 - What fork would you want on a non-lugged bike?

    Does a lugged fork on a welded frame look better than a unicrown fork on a lugged frame? To my eye, possibly, but I'm not sure. I like a segmented fork on a welded frame, or else those antique non-lugged squarish crown forks... hey should bring them back.

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  5. I agree lugged frames look best with lugged frames, the cut outs, points and pinstriping pick up on each other and render the thing whole.

    Having said that the fork on my 2000 Bob Jackson lugged 531 absolutely sucks. The frame is sweet, but the beautiful, sloping fork crown 531 does an excellent job of ruining the ride. It's harsh, transmits bad feedback directly and generally shakes my eyeballs. It's by far the worst fork of any bike we have and, because of this element alone, the one I don't ride. This isn't to say a well-designed lugged fork can't ride beautifully.

    The cheap, unicrown Tange mtb fork I have rides, conversely, much smoother, damping high frequency vibrations (the most fatiguing kind) and flexes visibly while do it.

    I only care what kind of fork I have if it works for the intended purpose of the bike. Suspension or steel for mtb, carbon or steel for race bike, steel for general riding. It's construction method doesn't matter to me at all, aside from aesthetics.

    From a manufacturing standpoint adding a lugged fork will push a bike beyond a "normal bike price point" very rapidly, resulting in cost cutting elsewhere that affects the ride directly. They seem to have found a home in boutique bikes, though.

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  6. I agree that, in most cases, the unicrown fork doesn't look right on a lugged frame. They remind me of all of those bikes I used to see 10-15 years ago that had lugged frames but carbon front forks. The shape--and, in most cases, the color--were completely wrong.

    I also think unicrowns also don't look right with caliper brakes. Perhaps that's just because I became accustomed, over so many years, to seeing caliper brakes on bikes with lugged fork crowns, and lugged frames.

    However, there is nothing wrong with them functionally, at least to my knoweldge.

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  7. I think that if the maker has gone to the trouble of adding beautiful lugs they are missing the opportunity to continue with adding beautiful details to the fork. My CCM may be a clunker, but the lugs are pretty and the crown fork is similar to the Retrovelo crown fork. The peson who designed that bike really spent some time thinking about how they wanted it to look.

    Now, if they had only spent sometime adding a better quality bottom bracket.

    I guess that's the trade off. If you spend all your effort making it look nice, then cheap out on the quality to hit your price point the bike becomes disposable. My CCM would suggest that it has been a dilemma for bike builders since the sixties at least.

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  8. Jim - (neat, you have a Bob Jackson) How do you know it's the fork per se and not the bike in general? The fork is not the only factor responsible for ride quality. I sense no difference in bikes I've ridden based on the lugged vs unicrown fork distinction in itself.

    Justine - I think I agree re the caliper brakes. I couldn't put my finger on it, but I guess the forms are too similar and there is an overall cluttered look.

    Erin - As beautiful as that fork crown is, I doubt it was expensive to produce at the time; pretty standard on all sorts of "Sears-type" bikes back then. Sigh.

    The thing about sub-par framesets vs subpar components, is that the latter are always easier and less expensive to upgrade.

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  9. As long as the fork is in concert with the rest of the design, I don't mind. The Abici is visually jarring in the photo because it appears inconsistent.

    I like a lithe lugged fork on a road bike for the dampening effect on the ride quality, and a robust unicrown on a mountain bike. The narrow tubed unicrowns kinda weird me out, like an escapee from the island of Dr. Moreau.

    The V brake setup on the Urbana looks awry. I remember some mention was made of difficulty with setting them up. Try swapping the fat and thin spacers on the brake posts if you haven't done so.

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  10. Hmph. Don't go insulting the Bicycle of the Gods! You never know when it will throw down the hammer and smite you.

    http://rideblog.wordpress.com/my-bikes/the-89-panasonic-dx-5000/

    I think my Panasonic is gorgeous, unicrown fork and all. And yes, it's lugged. Being a small frame, those lugs and the unicrown are right next to each other. And I like them! In fact, I defy anyone with even the smallest bit of good sense to dislike the Panasonic and its epic purple-ness. Admit it: you can't.

    I like a pretty lugged fork as much as the next person, but when the unicrown is part of purple heaven? Veloria, you better watch out. I feel a lightning zap coming your way... The Panasonic is frightening in its lightning-bolt fury (really, it even has lightning bolts on it).

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  11. Experience. Lots of it. Riding consciously.

    I can feel where the vibrations are coming from, either from the rear, middle or front and try to figure out why each feels how it does. When I say sweet riding it means the frame is well-damped and provides a lively, efficient yet not harsh ride. That is the rear and middle, all else being constant, and I feel it through my feet, butt and body. I feel the front through my hands. Certain frames have a certain sound, and I'm not referring to mechanical clanking. Some forks have it too. That contributes to the feeling from the front. I can feel the fork flexing front to back. That's where a lot of the shock absorption happens, on that plane. I can tell if the fork legs are flexing or the steerer or both. It's not a special gift, it's just experience.

    Bear in mind I didn't say I could feel the difference between a lugged fork and a unicrown. I said my fork, which happens to be lugged, feels like crap and my other, which happens to be unicrown, feels pretty good.

    I referred to it earlier but I think good design, regardless of construction method or material, trumps all.

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  12. The crown on the antique is prolly not really an unicrown, its made from a curved crowns, blended into the blades that has been brazed on. It would be impossible to make the brazed joints stuctual like that, methinks!

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  13. Velouria - Couldn't agree more. Even simple lugs such as on my 80s Galaxy are so much more appealing than a unifork, especially as you say, on a lugged bicycle. And then you get beautiful fancy fork lugs such a on my friend's Hilton Wrigley that complement the frame lugs in such a way that transcends engineering and ventures in to the world of art (in my opinion :) ).

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  14. A lugged forks looks just fine with a TIG welded frame.
    somafab.com/bvista.html

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  15. I think you kind of need to get over yourself on the lug worship. A TIG crown on a fork lets the manufacturer get whatever geometry they want with basically no upfront tooling or ongoing inventory costs. These days there's only a handful of 'lugged' crowns more than 48mm wide on the inside and they're all expensive because of low production.

    Lugs were originally a labor-saving device and nothing more — they let you get away with minimal tooling — don't need a fancy jig, with stout lugs you don't really have to miter tubes, you can even braze over a central hearth instead of with a torch (hugely important in the age of coal). The old-world "dutch bike" manufacturers like Gazelle and Batavus still use lugs this way, but only really out of institutional inertia. There's also Worksman in the US, Flying Pigeon and clones in mainland China, and the multitude of Indian manufacturers of bizzaro british rod-brake roadsters.

    But nobody else would dare make bike frames in such a slipshod manner these days — you'd have a really hard time finding a shop in taiwan willing to use such crappy construction techniques. Without the institutional inertia it's actually cheaper to miter the tubes correctly, braze in cast dropouts instead of crimping them, and use cromoly instead of 3x as much mild steel (or often pig iron!). Replace lugs with TIG and the efficiencies cut the price dramatically again (even though the welding labor is more expensive).

    On the other hand you have the NAHBS crew that use lugs purely as a labor-wasting device — something to dump endless time into filing and fussing over. On top of that lugs can only really serve to make such a frame less custom, since their availability harshly limits the possible geometries. Despite what Grant Petersen says they actually make a tube much more labor-intensive to replace after a crash. Fillet brazing uber alles!

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  16. My 1897 Shelby Ideal has a fork similar looking to the Sterling pictured. The top curved section appears to be cast from a single piece of steel. The fork blades are rolled into a tube, brazed, flattened, and brazed to the curved top and filed to eliminate the visible joint. I sandblasted it and could see the seams. So I guess technically it does have a crown, it's just curved. On a side note I read that Shelby was the first company to make steel tubes specifically for bicycles.

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  17. I see the logic of what people are saying here, but on my Abici (which is grigio - a pale grey-ish/cream-ish/beige-ish colour) I *positively* like the unicrown fork! Heresy! But I think the overall simplicity of the bike is key, even though the frame is mostly lugged, and that the unicrown fork contributes to that fluidity and simplicity - maybe more so in a colour like "grigio" than in the violet pictured above?

    My other lovely Italian bike (the Orco cicli Ariel) *does* have a lugged fork and it looks great (but the design is different in other ways, too, and I have it in a much stronger colour - a dark bluey-green). But I can see reasons other than cost cutting for Abici to have made a different choice (that is, maybe they made the choice because it's cheaper - I don't know - but I think it works aesthetically, at least in a neutral colour where the simplicity of the bike design is most marked.)

    Velouria has taught me to notice the seat stay clusters (I may have misremembered what they're called), and I *do* wish that everyone made those as beautifully as the most beautiful ones (the Abici is great there). E.g. I'm not crazy about the bolt design on the Pashley, and I agree with what Velouria has said in the past about Betty Foy there.

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  18. Velouria, you do seem to be sensitive to this particular anatomical item. Are you perhaps a "Fork girl"? I'm into them as well but my REAL fetish is for Italian drop-outs.

    I'm partial to unicrown forks, probably because when I was a kid and BMX bikes were still exotic and almost unknown in rural South Texas, a unicrown fork was one of the unique things about a real BMX machine and a sign that whatever bike was sporting it was the real deal from CALIFORNIA(!)and not some knobby tired fake from Sears or Western Auto.

    The sexiest unicrowns to me are the ones where the tubing meets the steerer at less than a right angle and has an angled slice at the bottom with a wedge shaped fork end that extends the axle below the end of the fork leg (pant, pant...ohh yeah, just like that...) A vintage SE Landing Gear fork (the 20" version as fitted to P.K.Rippers, in Blue or Black) being the Farah Fawcet of my particular(sad) bike fantasy.

    I don't like unicrowns on skinny tired bikes. Period. But rigid MTBs NEED them for similar reasons as above. The first Mountain Bikes had flat-topped forks that, while nice looking as forks, were part of the aesthetics of bikes that seemed to me to be awkward, uncomfortable hybrids between Roadbikes and Dirtbikes. They go together like a Mullet and a Tuxedo. My 1983 Shogun Mountain bike has a beautiful flat-top Tange fork with 4 eyelets and lovely tapered legs and flawless workmanship. That bike looked such a dork as an off-roader. I converted it to a touring-heavy-duty commuter and it's really nice looking to me now.I still ride stairs on it and it seems happier now.

    I think the fork on the Sterling you show is not really a Uni-crown by the way, at least not in the modern sense. That type of fork was popular for a long time and I'm not sure why you don't see them much anymore. The whole top/crown section is a forging and the legs are flattened tubes brazed on to it. I think i can see something that looks like the joint in your picture. There are also lots of similar forks where the entire fork except the steerer is a one piece forging. They are commonly called Ashtabula forks after the company that made many of them, which was named after the city in Ohio where the factory was(is?). You see them mostly on old Schwinns. They are really neat forks. Lively, strong as liverwurst, and (like it mattered on a bike like that)VERY aero. They aren't really any heavier than other forks for the same type of application either. They look best with a chrome cap and a pinstriped chevron right below the cap. Check out some 50s 60s Schwinns. They are, like, so hot in that area.

    Have you ever seen a lugged Unicrown fork? There is such a thing. Tange and a few other makers produced forkcrowns where the steerer had nicely scalloped short lugs on the side complete with tasteful little points. The legs were brazed into the lugs instead of being welded onto the steerer. I'm not sure when they stopped making them, I still have a few Tange frame component catalogs back to 1992 and they no longer listed them then. They were neat but nothing to get excited about. Like a great haircut on your Mom.

    Well, thats about all we have time for on this edition of "Spindizzy's Old Time Bicycle Hour", join us next week when we reminisce about how we made bike tires from gardenhose and rubber-cement "back in the day".

    Am I really this pathetic?

    Spindizzy

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  19. Oh, I also want to say that EVERYTHING about that Sterling pathracer is just so fine. The bars, the fork, the headbadge. The EVERYTHING.

    The tires are way too wide and heavy for what this bike was built for but they have that funky chain tread pattern that I like so much. I wish someone would make modern tires with chain tread or the old NON-SKID pattern where the tread was just NON-SKID spelled out in block letters at a jaunty angle across the tire. You can buy them for old cars again(they are just the thing for model T Fords) but not for bikes. You can buy flame treads and tires with dumbass tattoo-style skull patterns though.

    Spindizzy

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  20. OK, I'll be contrary. I'll go ahead and say that while I think it's certainly easier to make a crowned fork look classy and refined, I really like the Abici unicrown you have pictured. I think the designer(s) did a great job making the junction look clean and well-integrated with the front of the frame. I'm not really sure, but it almost looks like the steerer ends in a single "lug" and the tops of the fork got brazed in. I think it looks great. Even the curve of the brake caliper follows the curve of the fork blade so cleanly. Bellissima!

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  21. Hey Erin B. I'm not sure what your bikes bottom bracket situation is but if the problem is that it's bottom bracket is for one piece cranks you can easily and in-expensively install an adaptor spindle that will allow you to use a nice alloy 3 piece crankset on it. They are even available with sealed bearings. "Consult your bike doctor for details and to see if this is right for you."

    Spindizzy

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  22. There's another type of fork crown that hasn't been mentioned, but appearance-wise, it's a hybrid between a lugged fork crown and a unicrown (although technically it is lugged):

    http://www.flickr.com/photos/21306332@N07/4253334982/

    http://www.flickr.com/photos/studiobeeldruis/4333861955/

    The blades are indeed brazed onto inverted lugs (i.e., the blades act like the lugs) and the brazing is filed down flush with the crown. Not sure what it's called. What's your take on them? They are generally considered desirable among the high end C&V community, and were found on the some of the highest end lugged lightweight road bikes back in the day.

    As for ride quality between unicrown and lugged: there should be no detectable difference. 99% of the shock absorbency is accomplished through flexing of the lower half of the blades, and is dictated by factors such as wall thickness, blade diameter, metal composition, and curvature. There should be zero flexing at the crown.

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  23. A fork can look good or bad, but one of the main purposes of the fork is to be the front suspension of the bike. I want a fork to be flexible and springy, to cushion all those bad bits in the road.
    In that respect, it is more important to the ride than any other element of the frame, and second only to the tire. If a unicrown fork will suspend as well as a blade & crown fork, it has my blessing, but I suspect that it won't, because it is not designed to be.
    Can it be?

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  24. Thanks for pointing out a design feature that I hadn't thought much about. You are very detail oriented, Velouria. But then I'm the kind of guy who sees nothing wrong with wearing brown loafers and a tux.
    In our stable of bikes, the lone TIG-welded bike has a unicrown fork. The lugged-frame bikes all have flat-top forks. My vintage lugged Stumpjumper from 1983 has a really cool biplane fork. Later Stumpys went the unicrown route until suspension forks became standard equipment.

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  25. More and more, reading this blog and thinking about bikes (I spend an inordinate amount of time around bikes these days) I'm beginning to think of lugged bikes as an anachronism (I know, heresy, etc.) I know that they are easier for small manufacturers to make and allow a level of artistry that has not been approached in TiG-welded frames but I think this is mostly because TiG-welding is inaccessible to small shops. As the technology progresses, I expect small shops to adopt TiG welding and think they will eventually produce bikes that fascinate your eye, Veloria.
    Moseying back to the point of this blog entry, I agree with you about the inconsistency in design of a unicrown fork when coupled with a lugged frame. Nothing else on the frame is bent that much (on a diamond frame, nothing is bent much at all) and the lugged fork conveys a, dare I say, masculine aggressiveness to the approach of the bicycle. It announces itself; the unicrown fork sort of drops its shoulders and slides into the room.
    But I do look forward to seeing what small artisans do with TiG welding once technology and fashion lead them to adopt its use. I doubt the unicrown fork is the final word in TiG-welded design. It looks preliminary and unfinished.

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  26. Velouria - re: old bikes without fork crowns.

    I believe those older bikes do not have "unicrown" forks, technically. They appear to have flat-bladed forks which are bent at the top, and welded or brazed to the stearer tube.

    A modern (BMX or Mountain Bike style) unicrown fork has round, tubular fork "blades" which curve together at the top, where they are usually welded to a vertical tube which continues up into the headset. This design is strong, due to the wide, tubular structure and lack of stress points, and less likely to break on rough off-road terrain or BMX jumps, compared to some lugged designs. (Lugged forks are plenty strong 99% of the time, including light off-road trips and most "freestyling") And of course they are cheaper to make.

    Most older "cruiser" bikes, from the 30's thru 70's, used a design that looks similar from the side, but actually consists of a flat fork blade on each side, which come together at the top, welded to the bottom of the steerer tube (I think), eg: http://www.flickr.com/photos/45473072@N03/4686689163/

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  27. Ground Round Jim said...
    "Bear in mind I didn't say I could feel the difference between a lugged fork and a unicrown. I said my fork, which happens to be lugged, feels like crap and my other, which happens to be unicrown, feels pretty good."


    I misunderstood the conclusion you were making. That of course makes sense. I too think that I can feel the frame vs the fork vs the wheels/tires, as far as ride quality goes, and people are usually skeptical.

    snarkypup - Have no fear, my lugged crowned roadbikes shall stand like an army of handsome soldiers against your Panasonic's wrath.

    Fred Blasdel - I think that many would disagree with your assertion that framebuilders use lugs as a "labor wasting device." There are multiple points of view out there, and the world is a better place for it. Mine is just one point of view; yours is another. I don't think it's necessary to tell anyone to "get over" anything.

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  28. Well, the unicrown is stronger, lighter and cheaper to make than a lugged fork. If you want disk brakes, you'd probably want a unicrown to support the greater torque, and also to suuport the greater forces of mountain biking. Probably not that important for a utility bike, though.

    Would putting lugs, that cover the welds at the join with the steerer tube recover the asthetics of a unicrown on a lugged bike?

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  29. Well, you've done it again Velouria: Introduced a highly-inflamatory topic and totally polarized the blogosphere ; ). But seriously, I again find myself appreciating this blog more and more as your writing expresses my thoughts and inclinations so well. This, despite differences in age, gender, riding style, etc. I agree with you and most of the respondents about lugged forks. It's also interesting to read the history and technical facts about forks offered by others here. There's always something to learn. Yes, there is room for multiple points of view and let us not forget that the name of this blog is Lovely Bicycle! Steve in MD

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  30. somervillain said...
    "There's another type of fork crown...:

    http://www.flickr.com/photos/21306332@N07/4253334982/
    http://www.flickr.com/photos/studiobeeldruis/4333861955/

    The blades are indeed brazed onto inverted lugs (i.e., the blades act like the lugs) and the brazing is filed down flush with the crown. Not sure what it's called. What's your take on them?"


    Ah, I've been wondering about those! That must be how the antique "flat crownless" forks are made as well. I like them. On a lugged bike, I still think a lugged fork looks best. But I think these would be perfect on a nice fillet-brazed or TIG-welded bike.

    It surprises me that I have been unable to find anything like a "fork crown encyclopedia" online, showing different designs and explaining how they are made.

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  31. I think I hate them! The wishbone forks (or is that term already in use for a different kind of fork?) on the expensive bikes down at the LBSs look exactly like the wishbone forks on the rusty WalMart throwaways down at the Goodwill.

    My idea of an attractive fork is the old Chicago-made Schwinn tubular fork as used on SUBURBANS. Besides, that fork gives a very nice ride. Now on the other hand, the old Schwinn blade fork as used on the VARSITY and darn near all the old 26 inchers is way too stiff a rider for my tastes; not the best looker either, but still better looking than today's wishbones.

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  32. Lugs are not just for looks, they are not "time wasters" at all. Its a framebuilding technology that allows the builder to be very gentle on the material with his/her torch. As far as handling goes the fork is the biggest factor, a crown lets us make in many varietys. Unicrowns, by their design will have to be close to round at the steerer joint. The sectional shape is one of all the factors the builder can play with. It´s unwise to call one techiqe superior to the other, they all have their uses! I even think aluminium frames are good, so is suspesion forks...no superiority in the workshop please!

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  33. "Do you care what kind of fork your bicycle has? What do you think of unicrown forks - in of themselves, and in combination with lugged frames?"

    While nice to look at crowned forks offer more opportunity to fail due to the multiple joints used in their construction. They also are very labor intensive when the buying public only cares about price. Uncrowned forks can also be more easily repaired if bent.

    That said, I don't care that my bike doesn't have a crowned fork since it is pure function that matters most of all not looks.

    Oh yes, that's a nice yellow bike! :^)

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  34. Anonymous 7:02 said...
    "A lugged forks looks just fine with a TIG welded frame.
    somafab.com/bvista.html"


    The Soma Buena Vista mixte is an interesting design, in that it has some lugged details (the connectors between the stays and the main tubes) as well as collars(?) on the seat tube and where the headtube lugs would normally be. The sloping lugged fork crown matches these details nicely.

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  35. To me a lugged frame bike with a unicrown fork is like a well-dressed person in bad shoes. They say that reveals a lot : )

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  36. When I decided to get the Soma Buena Vista I was disappointed that it was not fully lugged (however, to get a fully lugged twin tube mixte you pretty much have to get a custom frame, so I didn't have much choice). The few lugged features and especially the lugged fork crown redeemed it sufficiently for me to be happy with it. I don't think it would look as elegant with a unicrown fork. In general, I think a lugged fork can go fine on a welded frame, perhaps depending on the overall look of the frame (in the Buena Vista case, the frame is not purely welded, so it all works well together), but not vice versa - I don't think a unicrown fork on a lugged frame ever looks good.

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  37. i agree from an aesthetic point of view..lugs look better, but i am sure they all perform just fine.. check out the 2 coolest forks(IMHO) look up Yo Eddy Fat Chance forks and Wound Up Carbon forks..they both handle great and provide a bit of shock absorbtion..

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  38. Hydroforming plus aerodynamics can result in rather pleasing aesthetics:
    http://www.flickr.com/photos/henryinamsterdam/5400516536/in/set-72157625936612962
    but does it qualify as unicrown?

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  39. Frits - Not sure how that fork is made and out of what, but I like it!

    Kyle - the Yo Eddy fork is a segmented fork though, not unicrown. I agree it's one of the coolest forks out there. There are lugged segmented forks as well. The Woundup forks I would classify as "crowned" since they do involve inserting the blades into a crown structure. I like them as well; didn't know the manufacturer's name - thanks.

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  40. One interesting aspect to frame design is to compare the basic profiles of bicycles with layers in photoshop overlays. As I've been casting about for a new bike, I've done a lot of this lately.

    It's simple in even the most basic edition of photoshop to add a transparent layer or a layer at a dimmed opaque setting. Then using the apple key + T (transform) command to drag the image to the same size as any other image.

    Then it's possible to actually see the geometry of how the basic components compare one over the other. Transforming the color layers also makes it easier to keep the two comparisons separate. I suspect this might reveal a good deal about the distribution of weight and ride quality... but I don't ride enough different bicycles to know exactly.

    I'm also curious about those handlebar grips with a flared out surface. Since my standard handlebar grip often seems slightly painful after a while, I wonder if those help.

    :0)

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  41. Velouria, I agree with you. On cheap bikes...well, what can you expect? On more expensive bikes, however, the manufacturer should create a congruent design.

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  42. Sometimes unicrown forks w weird welds just look like tiny men in ill-fitting pants.

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  43. jn: do you mean like this?

    http://www.flickr.com/photos/7516215@N03/4377035591/sizes/l/in/photostream/

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  44. I'm sort of a vintage fork collector although most of what I have are lots of weird variations of the old sprung forks on old 26" balloon tired bikes. I like to stick a nice rusty bar and stem in them and a front hub(no spokes) and hang them on the wall(even better if you cut off the headtube so you still have the headbadge, just don't cut up a usable frame), it's the best bike wall art short of a whole bike and it hangs flat on the wall. To hang a whole bike flat you have cut off one side of the handlebar and saw off one side of the crank.

    I wish I could find examples of all the forks we've discussed here to hang on the basement wall.

    Spindizzy

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  45. Funny the details we focus on. I have both a Yo Eddy and a Trek 520, both wonderful bikes to ride. The aesthetics of their forks means nothing to me. On the other hand, I have strong opinions about sentence punctuation that I sometimes need to stifle, as it can interfere with my appreciation of the piece as a whole.

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  46. Anne - Just try to re-imagine my sentences written the way you like. For instance, when I see "Yo Eddy" I tend to mentally insert a comma and an exclamation point.

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  47. Apparently a lugged crown fork is like sugar on my corn flakes...

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  48. Spindizzy said...
    "Anonymous said...
    Velouria, you do seem to be sensitive to this particular anatomical item. Are you perhaps a "Fork girl"? I'm into them as well but my REAL fetish is for Italian drop-outs."


    I guess I do fetishise fork crowns more that the frame's lugwork. I am okay with a wide variety of lugwork on the frame itself, but have very specific styles of fork crows that I prefer. The multi-plate crowns are by far my favourites. After them come the flat-tops. Drastically sloping and round crowns I don't like as much. Segmented forks I swoon over and would get a TIG-welded bike just for the segmented fork... Crazy.

    "Have you ever seen a lugged Unicrown fork? There is such a thing. "

    Do you mean something like this? Or do you mean when the crown itself is round?

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  49. I have two unicrown forked bikes - one from '94, the other from '54 (a Schwinn World). Both have non-lugged frames, so I think they look OK.

    Personally, I'm OK with lugged forks on a lugged frame, and a welded fork on a welded frame. A mix of the two seems wrong to me.

    That said, I've got an '87 Cannondale Black Lightning that's all brazed together (it's smooth...kinda like an EF or brazed Schwinn frame, but oversized aluminum) but is wearing a lugged chromoly fork. To me, it looks like wearing a bowtie with sweat pants, but I love the way the bike rides so much that I can't complain too much about it.

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  50. Peter said...
    "Would putting lugs, that cover the welds at the join with the steerer tube recover the asthetics of a unicrown on a lugged bike?"


    Good question. I guess I'd have to see it. But I think putting decorative lug sleeves on the fork would cost the manufacturer more than getting a lugged crown fork would to begin with. The wholesale prices on generic lugged forks aren't all that much higher than unicrown forks.

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  51. Being old enough to have been a kid when the roads were populated with cheap bike boom era ten speeds lugged and brazed frames they just don't seem as special to me as to some people. My first bike as an adult was my dad's old Apollo. Lugged, brazed, 45 lbs....

    That said, a unicrown would look kind of out of place on a bike which otherwise went for a traditional look.

    Of course I also own a 93 Cannondale Track which is the complete opposite of this situation: oversized tig welded 6061 aluminium frame combined with a lugged and brazed steel fork and for some reason I actually LIKE the visual dissonance in this case!

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  52. Well I'm old school, I have a TREK 730 all lugged including the fork crown, a Heron, same thing. a Windsor also lugged. and when I build a frame its gonna be lugged with a Pacenti double plate crown. and oh yes I'm jonsing for a Hetchins. I just love all that rococo lug work. It shows that a real human being made the bike not some Damned robot squirting resin. I know I'm an old curmudgeon but that's how I roll.

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  53. Joseph E said...
    "Most older "cruiser" bikes, from the 30's thru 70's, used a design that looks similar from the side, but actually consists of a flat fork blade on each side, which come together at the top, welded to the bottom of the steerer tube (I think), eg: http://www.flickr.com/photos/45473072@N03/4686689163/"


    Thanks, that is exactly the flatter design I was thinking of. i really like the way these look. Would love to see one "naked" and get a better idea of how they are made.

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  54. Velouria, yep, that's the thing I was thinking about.

    I think it''s a little ironic that it doesn't come across as more appealing(at least to me). You combine the structural and aesthetic advantages of lugged construction and combine it with one of the BMX and Mountainbikes most iconic elements, it should be dynamite. But it just isn't.

    The stacked plate forkcrown that you find so attractive is just the opposite(I think). I believe that that began as a lowcost way of making forks as inexpensively as possible with a minimum of precision equipment. You just take 2 or 3 of these plates(whacked out with a giant punch press by the crate) and drop a steerertube into the big hole in the center, then slip the forklegs into the oval holes on the ends. If it needs to be particularly strong you just add another plate. Simple, self aligning and if the fit is snug enough you can just pitch them into your brazing oven in a pile and they come out straight. But somehow it is such a satisfying thing aesthetically.

    I always thought of them as a sign of a cheap bike because so many cheap bicycles used them. But they really are ingenious and like so many ingeniously simple things only need to be made with care to become really attractive.(I almost said noble. Then everyone would have known I was full of crap)

    It's fun to really obsess on the little stuff sometimes and the bicycles small private bits are as worthy as anything else and they don't seem to mind.

    Spindizzy

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  55. No Nickname said...
    "I see the logic of what people are saying here, but on my Abici... I *positively* like the unicrown fork!

    My other lovely Italian bike (the Orco cicli Ariel) *does* have a lugged fork and it looks great (but the design is different in other ways, too"


    I am really interested to know the differences in ride quality between your Abici and the new Orco. How similar vs different are they?

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  56. Spindizzy - A related question: Why is it said to be easier to make "stacked" plate forks for bikes with wider tires?

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  57. Hello Velouria -

    I'm still trying to break down the differences between the Abici and the Ariel, because although they're much more like each other than like anything else I've ridden, they are different in the frame angles, stem height and handlebar shape, and in more specific superficial things: saddle, tires, and 3-speed Ariel vs. single speed Abici with its coaster brake. So I'm still trying to work out (as far as possible given my ignorance/inexperience) what's about the geometry of frame + handebar set up etc, and what's gearing, saddle, tires. Both are light (the Ariel is unbelievably light and very small indeed - perfect for me!), and both are responsive but stable (they've been making me much more confident about steering because they're so trusty).

    So far I've only gone about 8-10 miles in one go on either, but the Ariel feels as if it could go much further and remain comfortable (the Abici too if it weren't for hills, my inadequate legs, and the saddle). The Ariel is not *cushy* like the Betty Foy (it doesn't give that extraordinary feeling of being wafted along on the kind of pillow that the princess and the pea would like), but it's very comfortable indeed, although I'm still getting used to a relatively leaned over position (much shorter stem and less curvy handlebars) and have to remember consciously to use stomach muscles instead of wrists for support! The angles are more relaxed than the Abici, which is the funny thing - the handlebar set up means I'm more upright on the more aggressive bike, and then on the more relaxed bike I'm in a consistently slightly leaned forward position.

    The set up puts me in a completely upright position in the Abici, and I've kept the B17 saddle, which is a weird combination. I'm torn because I like the simplicity and non-squeakiness of the B17, and I like that it forces me to ride more aggressively because it makes itself felt if I just sit down all the time! I generally take the Abici for short (1 hour including stops) rides along the river bank, where the only "hills" last about 5 feet.

    On the Ariel I have a front basket as well as a slender rear rack (as you said about the Bella Ciao, this is not a bike for hauling - I carry small amounts of groceries, but not a weekly shop). On the Abici I have a solid rear-rack and nothing at the front. I haven't figured out how that affects things, either - certainly the Ariel likes having the basket, but doesn't like it if I put two dozen eggs in there (that was the heaviest it's been so far!)

    OK, this is still a muddle, sorry!!!! I'll try again some time if/when I ever feel I understand the differences better! Sorry! My guess is that the Ariel is closer in geometry to the Bella ciao than to the Abici, from what you've described, but I'm SO SO ignorant, and it's unusual lightness/delicacy makes a difference, too (it's noticeably lighter than the Abici). I don't know. Still a mystery to me.

    Oh, and one more superficial thing: I LOVE the bottle dynamo on the Ariel! I changed the front light so that it's really bright for potholes (and smaller, fitting easily tucked in under the basket), and it's perfect.

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  58. No Nickname said...
    "...the Abici and the Ariel...they've been making me much more confident about steering because they're so trusty"


    You know, I also find the few Italian city bikes I have tried - including Abici, Bella Ciao, and a vintage bike with the same basic form - to have exceptionally stable steering; I feel like I am in more control of it on an Italian bike than on a Dutch bike. However, not everybody agrees and some find them "squirrely". Just goes to show that it is all a matter of taste.

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  59. To add to my unhelpfully vague Orco/Abici comparison, I think that my *perception* of the two bikes affects how they feel to ride, too. (This relates a bit to what you were saying about what seems v stable/responsive to us seeming squirrelly to others!) The Abici has become a purely frivolous bike, just for fun rides (for the time being, unless/until my legs get stronger and I get really comfortable with a coaster brake in traffic). The Ariel is also lots of fun, and I do take it out on Sunday mornings just for the sake of it, but it's primarily designed as my getting-around-town bike, replacing the car I sold. Not actually a commuter bike as such (I walk to work), but very much a functional, all-round ride.

    So on the Abici, because I associate it entirely with freedom and frivolity, I'm more likely to tear down a stretch of path as fast as I can, whenever there's a good straight run with no one around and no muddy puddles taking up the whole path, etc. So the types of riding I do on the bikes are as different as anything else.

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  60. "No Nickname said...
    "The Abici has become a purely frivolous bike, just for fun rides (for the time being, unless/until my legs get stronger and I get really comfortable with a coaster brake in traffic"


    Wait, do you mean to say that the coaster brake feels difficult/effortful to activate? If so, the brake may need adjustment. A well adjusted coaster brake should not be hurting your legs.

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  61. Oh no, I was just being unclear! The coaster brake works fine as a brake - I like it. It's just that I'm a clutz and my legs aren't very strong yet, so I find it too fiddly when setting off after a stop - i.e. I'm already slow to accelerate, which makes me anxious about keeping people behind me waiting - drivers round here are mostly very courteous and considerate. So the coaster brake exacerbates that worry because I'm very slow to learn how to stop in a good position for getting started again. In general am a very very slow learner with mechanical/practical tasks.

    But mainly I was referring to two separate issues - (1) I find the coaster brake pedal positioning thing awkward when stopping and starting with people waiting for me, (2) having a single speed bike in a somewhat hilly town means that I get off and walk a lot, because my legs in no way compensate for the lack of a low gear. But I LOVE having the single speed, for a bunch of reasons, so it's totally worth it.

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  62. Velouria, I think(and it's just spekelashun)the advantages of stacked plate fork crowns are that as long as the holes in the plates for the steerer and the blades are nice and precise, when you slip all the pieces together they self align. No jigs, no opportunity for things to slip or move around from heat etc. and the whole assembly is open enough to get brazing filler to every part of every joint. Some of them even have the plates formed with an offset that by alternating, one up, one down, one up, you even eliminate the need for spacers between the plates. Whoever invented this came to the shop with his brain in the "ON" position that day.

    I suppose that the advantages for making them for wide tire bikes is that it's probably almost impossible to find anyone making nice crowns for wide tire bikes anymore, so if you have to fabricate something this is a great option for all the reasons above. I know that it's definitely the approach I would take if I was making a crown from scratch. The best part is that you eliminate the need for a fork jig. I've made a few forks(from ready made crowns and blades and by making custom legs from straight tubing to use in clamp-type suspension fork crowns for rigid jump bikes and Mountain fixies) and the jig was always the biggest hassle and impediment.

    All this talk about fork crowns just adds to my frustration with my favorite roadbike. I bent the fork slightly on my old 1979 Trek 970 and can't get it right. It won't track right hands free at all and it looks just slightly off. I'm going to try again but if I can't make it right I'm screwed. I'll never find another original fork for it(it was made semi-custom after the regular production run as a favor to a racer who was "connected" and is sort of special, not really valuable but you know) and I couldn't make a perfect copy(the finish wouldn't match even if I could) and I refuse to put a crabon fork on it like everyone tells me I should. This bike stopped being just a bike to me so long ago and I can't be rational about it. Poor me.

    Spindizzy

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  63. Why not pay to have it looked at professionally then? Unless you think that is of no use.

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  64. MDI, I did and the options were to try to coldset it, replace the bent blade or make a replica. We went with the coldsetting option and it got better but not quite there. The other options require painting as the last step and it would mean trying to match the original finish and patina or repainting the whole bike and trying to either save or replace the original decals. None of which seems practical. This would be simple if it was any of my other bikes but as I said, I can't be rational about this one.

    We'll probably try to straiten it again and see if we can't get it right. If so I can continue to be irrational about it but if not I'll have to come to my senses and quit being so precious about it. After 25 years of it either being my only good roadbike or my favorite one maybe it's time to replace it with something new. Something new that is as old fashioned as I can afford that is. I wish I could buy a brand new 1985 Serotta custom made to my specs...

    Spindizzy

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  65. I wasn't talking about decorative lugs, but functional lugs to join the forks to a unicrown. I've actually seen these in the 80s so did a search and here is one:
    a 1985 StumpJumper
    http://www.flickr.com/photos/jimg/146592015/

    I have no idea if this technology is as cost effective or strong as contemporary unicrowns.

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  66. It's hard to believe that this post was authored by the same person who composed this post: http://lovelybike.blogspot.com/2011/04/design-for-use-versus-posturing.html only 2 weeks ago. Everyone has their preferences, but lugged crowns don't offer any advantages in utility over unicrowns. Arguably, the lugged crowns help primarily with curb appeal, accolades from the "elegant" set, and posting hott close-up pics of one's hott bikes online. In short, they are a posture-piece. While lugged crowns don't detract from a bicycle's utility (at least, not for the type of riding that this blog concentrates on), a preoccupation with such superficial details is certainly not utility-oriented.

    On the other hand, unicrown forks are cheaper to produce, (most often) stronger, and had enjoyed more cache on the sales floor at one time. Spindizzy's first dissertation above touched on this, and Peter's succinct response drove the point home: lugged fork crowns and flat-plate forks don't hold up well to offroad abuse. BMX bikes and fully-rigid MTBs were the hot technology 20-30 years ago, and the best of these sported stout, unicrown forks, often with straight, tubular blades. As this was the hott ish at the time, nice pavement-oriented bikes started gettin them, too. The manufacturer's enjoyed the decreased expense, and the customers enjoyed having the "modern" fork, which was often less-prone to be bent then lugged crown forks. In time, manufacturers started making sleek, attractive unicrowns, like the one on Snarky's Panasonic. We're seeing a similar trend now, only far more silly: folks are buying road machines with disc-brakes, as these offer the "best" technology/stoping power. (They also cost/weigh alot more, and require more maintenance, but who cares? Many consumers demand the hottest equipment, regardless of actual needs.)

    As for what looks good with what, this is entirely subjective. There are lots of schools of thought on cycling fashion(an oxymoron if there ever was one), and the fact that so many ppl are conforming to the Riv
    aesthetic is, in my view, kind of disappointing. My LHT is TIGged with a sloping single lugged crown; never bothered me. My 1988 Miyata TerraRunner is lugged with a tapered and raked unicrown; it looks a bit off, but it's original and, therefore, period-correct. I could easily swap forks between the two; they share similar dimensions, but I could care less. Both forks function perfectly where they sit now.

    There are times when I'm a slave to fashion. I recently bought a worksman INB frameset, and the massive, hideous unicrown fork that they currently put on those ended up being replaced by the sloping lugged crown model that they'd used a while back. I did this primarily b/c the newer forks are designed to be run with worksman's proprietary front drum; i'm running a SA. I could have tried to modify the fork *or* the SA brake-arm, but figured that it'd be cheaper/easier/safer to buy a used lugged-crown version. So, I did it for utilitarian reasons, but I have to admit: it looks soooooooooo much better on the frame.

    regards
    -rob

    ps- far more important aspects of fork design exist, and will have more of an effect on the ride than the crown ever will. If you're looking at your fork while riding, you're probably not enjoying the ride.

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  67. Screech said...
    "It's hard to believe that this post was authored by the same person who composed [the use vs posturing] post 2 weeks ago."


    What's hard to believe is that we actually believe ourselves to be consistent and linear. We are not, none of us. Embrace inconsistency, I say.

    "lugged crowns don't offer any advantages in utility over unicrowns"

    Debatable, but also beside the point.

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  68. There is a fork that bridges the gap between lug point artistry and tube bending know how, it is the fork that Charlie Cunningham and Steeve Potts made some 25 years ago. It also was one of the best mtb fork then.

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  69. Thanks for educating me about the difference between a traditional fork and a unicrown fork. I agree that some can find fitting a unicrown fork on a lugged frame is like wearing suit trousers with Nike Air Rifts. But, from a performance/durability point of view, is there a difference?

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