A Rake's Progress
Over the summer I wrote about a dream project I had instigated with Bella Ciao Bicycles: They were to send me an upright step through bicycle (the Neorealista model) with two forks - their standard fork, and an alternative, low trail fork. I was to try the bike with both forks and tell them what I thought of the difference.
To re-cap for those who are not bike geometry geeks: A bicycle's trail, in layman's terms, has to do with how far forward its fork blades jut out (i.e. the "rake"), in relation to its headtube. The more forward the fork, the lower the trail number (measured in mm). A trail figure in the 50s is said to be neutral or mid-trail. A number in the mid-60s or higher is considered high trail. And trail in the 40s or lower is considered low. This aspect of a bicycle's front-end geometry is thought to affect handling in a variety of ways - notably, its steering behaviour and its ability to carry a front load (you can read more about all that here). While most bicycles produced today have trail in the mid to high range, trends in this respect have varied through the decades. And increasingly, manufacturers are beginning to experiment with low trail again.
Despite my casual use of the word "experiment" here, there is no question of this project being an actual experiment in the scientific sense - if only because the tester (myself, that is) was aware from the start of which version was which, and had pre-conceived notions of what to expect from each of them. But I think that, at least in theory, it would be possible to arrange a blind test of this bike with the two forks. As you can see in the photos above, the visual difference is quite subtle - so that unless testers are equipped with tape measurers or pay attention to small differences in the distance between their toe and front tyre, they might very well not know which version they'd be trying, even after switching from one to another.
In any case, here you can see the bicycle in the before and after state for comparison. The standard fork is fitted in the top photo. The low trail fork if fitted in the bottom photo. Now, as far as concrete figures, the only one I can give you is that there is an inch difference between the rakes. As Bella Ciao does not release its geometry charts, I cannot give official trail numbers of the two forks. But according to my own guesstimates based on crude measurements, it is something like 65mm for the standard fork and 40mm for the low trail fork. This latter figure is at the high end of what is considered "low trail" territory, so it was really a rather conservative alteration. Nonetheless, the difference should produce some corresponding difference in the bicycle's handling.
Excited to experience these differences, I set off from the bustling metropolis of Limavady. Here I should explain that when it came time to fit the second fork I noticed a small problem (one of the fittings had been powdercoated over and required re-drilling), which caused me to seek the assistance of a bicycle shop. This actually worked out pretty well, as it resulted in back to back rides of equal distances, with the new fork tested while memories of the original one were still fresh on my mind.
Riding with the low trail forked bike in this manner, I immediately felt a difference. But that difference was not what I had expected. Rather than feeling a change in the handling, what I felt was a very distinct change in the feel of the road: The ride was noticeably plusher, cushier, less jittery over bumps and uneven patches - just overall smoother. This is not to say that the Bella Ciao is a rough ride to begin with. But those who switch to it from, say, a vintage roadster or a Dutch bike (which is often the case), will notice that it isn't quite as smooth. It is a far more responsive, faster, more lightweight category of machine. But you do feel the texture of the road beneath you a bit more on it.
Now with the low trail fork, I felt it only as a distant echo. The same 8 mile stretch of crumbly chipseal I had just cycled on with the standard fork, was now transformed beneath my wheels, as if a crew of pavers had arrived to smooth and polish its surface.
To investigate this side of things further, I veered off into the woods and rode along the unpaved forest trail for as long as I could manage before it disintegrated into MTB territory requiring skillz I lacked. Whether going over stones, roots or rutted-out stretches of hard packed dirt, I couldn't help but marvel at how much more dampened the roughness felt with the new fork. In truth I had not expected such a difference from the additional 25mm of rake. In fact, my expectations had been so focused on handling, I had forgotten to even think about any other aspect of things.
Now, as far as the handling itself (the way the bicycle steers, corners, etc.), in the first instance I was rather disappointed: I could not really sense much of a change. The main reason I love low trail bicycles, is that I find their handling more intuitive, particularly when cornering and maneuvering. On a low trail bike, I can take tight corners more confidently and at higher speeds; I can deal better with hairpins and tight alleyways. I also feel more comfortable riding no hands, or with limited hold of the bars. This time, however, I did not feel a pronounced difference in this respect; the bike just did not scream "low trail!" to me.
But as I continued to ride the bike on that and subsequent days, I began to notice that my behaviour on it was different than it used to be on the standard-forked version. Namely, I was multitasking more than previously - taking things out of my pocket, eating (I have a long commute!), checking my phone, removing and putting on articles of clothing. Clearly, I now felt comfortable enough with the amount of control I had over the steering to do all those things, whereas previously I didn't. Having noticed this, I immediately sent an email to one of the guys behind Bella Ciao mentioning it, lest I forget... and I did this while cycling (on a very quiet road, don't try this at home, etc.).
These differences aside, I do not yet have anything else to report. I did not notice any change in speed what so ever. No change in responsiveness or acceleration either. One nice thing about Bella Ciao bicycles is that they feel kind of racy and aggressive despite being utility bikes. The new fork did not diminish that character in any way. I have not yet tried the bike with a front load (ironically, it sports a rear rack that I designed a few years back), but that will happen soon and will no doubt yield a new crop of impressions.
The subject of trail is a rather tricky one to raise. It only serves to needlessly confuse those who don't know or care about it. And it can polarise those who do. Overall I prefer the handling of low trail bicycles, especially when it comes to upright bikes. But there are many who feel differently, and all of our preferences are valid, by virtue of being exactly that - preferences.
Considering my experience so far with Bella Ciao's experimental low trail fork, I can say that (1) I definitely prefer it to the standard fork, and (2) I think that for my personal bike I would prefer for the difference to be even more pronounced - another inch added to the rake wouldn't hurt!
But looking at it objectively, the current version of the low trail fork would certainly be more successful than my extreme ideal, as it is actually subtle enough in its effect on handling to appeal to a wide variety of riders, while offering vibration-dampening benefits that would be universally appreciated. At this stage, my suggestion to Bella Ciao would be to simply use this low trail version as their standard fork and mention nothing special about it. Or why not go all out and offer (albeit perhaps in small print, so as not to freak out the majority of their customers!) a choice of 3 forks: standard, low, and super-low trail. Whether they consider actually implementing this or not, is of course up to them. Either way, it is exciting to be a part of the R&D process of a company that is small, flexible, and - well, a little eccentric. Thanks Bella Ciao, and happy trails!
That really is a spectacular color on the bike. I've been waiting to see more of it since the sneak peak in a previous post.ReplyDelete
I very rarely carry loads on my rides. At least not anything more than what fits in either a medium-sized handlebar bag, or a small rear trunk-bag. As such, I generally have little concern with "load carrying" capabilities of bikes. I do, however, appreciate a plush ride. As such, I like a long wheelbase, whether that's due to a low trail fork or longer chainstays. The old "sports touring" geometry bikes from 70/80s seem to hit on it pretty well for me. Plus, they typically had a nice "banana bend" fork, (rather than these straight-legged things you see now) which absorbs tons of shocks from the road. They looked nice, as well as rode nice. I see that the low-trail Bella fork has a trace of this character.
I do prefer to front-load my bikes, but find that other factors (namely: how low the weight sits and how well it is secured) play a far, far bigger role in what that load feels like to carry than trail. So for me the trail and rake stuff is all about handling and ride quality.Delete
My view on chainstays is rather unpopular, as I prefer them as short as practicable on any bike, including transport bikes!
Well, this is a bit off-topic but it always baffles me that somebody can have an "unpopular" opinion on what they like in a bike. It's like saying that your favorite color isn't as good as mine. Just read the bike forums... heh. It is fortunate for you that you are able to identify characteristics that you like/dislike and are able to explore variations like these different forks. Fairly interesting to watch these sorts of things, to me.Delete
It seems that most modern (production) bikes have the same size chainstays across an an entire range of bike sizes from 49cm up to 63-4cm. They are built to optimize production/ storage/ shipping constraints, as I'm positive that you're aware. Grant Peterson has recently (not new for him, I know.) brought this topic up again. I suspect that those of us at the extreme ends of the height spectrum probably find this more interesting than those occupying the middle ground. I am very tall (36" inseam), so I find the bikes that I can ride (almost all regular/ easily accessible production bikes are too small for my tastes. 62-64cm can be made to work, if I'm lucky) having those "short" chainstays seem unbearably squirrelly to ride long distances. It's fatiguing after a while of that. A good portion of my riding falls squarely in the "tootling around" category, so I guess quick-handling or load-carrying don't really fall much on my radar.
Sorry, that was a bit "rambly".Delete
I have a bicycle which has 3 forks of different trail. It is interesting going from weeks of riding on one to another. Obviously, each has the same bearing set, and painted different colors for memory. The shortest rake of 45 is used mainly when I'm being "competitive". The mid rake of 55 allows me to have range of riding . the low of 65... general use.ReplyDelete
That is fantastic.Delete
Out of curiosity, what about the high trail fork makes it "competitive" vs the others less so?
My fast, lightweight 700C skinny tyre roadbike is mid trail and I love it. Sometimes I wonder whether I'd love it even more if it were low trail, but even if I were getting it built again I would still not chance it - only because I already know I love it as it is, and don't want to fix something that ain't broken. Alas it is not really suitable for a replacement fork experiment, as the headtube is too slack. Otherwise I would certainly try that on it.
I've never ridden competitively so may not be as much help as I'ld like.Delete
However, when riding my Spectrum which has trail around 55 or so steering is much quicker than my city bike which has trail somewhere just below 40. Presumably if you are riding in close quarters with other riders the ability to change course more abruptly might help. On the other hand, there have been times I have almost over steered when I hit a curve fast early on a Spectrum ride after extended rides on the city bike.
The Spectrum really dislikes weight up front. Even an overloaded handlebar bag feels as though it wants to take over handling.
This is a great and interesting report. The Bella Ciao is a wonderful bike. Hope they let you keep it.
High trail = small change in steering, large change in turning radius. If you're racing in a criterium or in a pace line and want to make a sudden move to catch everyone off guard, you want high trail. If you're in a peloton and someone makes a move, you want to be able to jump on their wheel.Delete
HIgh trail = competitive
low trail = cooperative
This bike with its pleasing curves and symmetry is drop dead seductive. Thanks for this interesting comparison! Jim DuncanReplyDelete
In the old days, frame builders and mechanics could adjust the trail by simply re-bending the forks. This can still be done with traditional steel forks and a bending jig (which should be easy to build).ReplyDelete
Of course if you do that you also have to remember that the length of the fork will change also.Delete
Right. Bending the blades will only get you so much extra rake before you have to also add length, assuming you still want to be able to fit your front wheel : )Delete
You can make your own. Here's an example: https://www.flickr.com/photos/115397703@N04/albums/72157652558911154Delete
Just thinking that ideally the bike designer might subtly change the head tube angle for low trail for and a high trail fork, additionally negating some of the difference.ReplyDelete
I guess it depends on what the goal is. If the manufacturer wants to improve vibration-dampening without changing front end handling then yes increase the fork’s rake *and* slacken the bicycle’s headtube angle to compensate. That way trail will remain the same, but the longer fork will improve ride quality (not to mention create an extra boatload of toe clearance).Delete
Remember also that the fork itself can only be described as high or low trail if the headtube remains constant (for instance, if two forks are supplied with the same frame). Regardless of rake, it does not really acquire trail properties until it sits on an actual bike.
True, but much of the difference in "feel" & performance regardless of trail would be a component of the rake. A slack head tube angle with a high trail would handle terribly, especially at low speed, conversely a steep head tube angle with really low or really high trail would be dangerous or at the very least disconcerting. Speaking for myself trail is nice to improve/soften out the ride as you say, but from a handling perspective I would concern myself with the fork rake more. I guess if you avoid the extremes you don't have much to worry about. - masmojoDelete
Could the difference in the feel of the road have more to do with the fact that the low-trail fork has more curve and more shock-absorption capability than the other fork?ReplyDelete
I'm just making this up, but I would guess that shock absorption increases as rake increases (decreasing trail), and as head tube angle gets more slack (increasing trail), because both would seem to make it easier for the fork to flex.
If only you could test the same bike with different head tube angles, varying the rake while keeping trail constant. That would be interesting!
Yes, exactly. It is the fork's long rake having that effect, regardless of trail (see also my reply to massmojo's comment above).Delete
The old roadsters I mentioned in the post were so crazy comfy precisely because they had these ridiculously raked-out forks, paired with very slack head tubes.
Roadsters generally have head tubes at a 66 or 67 degree angle. My DL-1 has 3 inches of rake. That makes it a very high trail bike. To be a low trail bike with that head angle it would need 4 to 5 inches of rake. I haven't seen a bike yet with that much rake.Delete
Loaded as a post a fork blade has a lot of strength. Loaded as a beam a fork blade bends easily. Stretching out at 66 degrees the blade is loaded both as a post (compression) and as a beam (torsion). It's in torsion much more than a blade in a more typical 72 degree head tube. That extra torsion is one of the main reasons the bike is so comfortable.
The other reasons roadsters are comfortable include the very long wheelbase. Long tubes flex more than short ones. If the roadster has rod brakes it has Westwood rims. Westwood rims are not shaped like boxes or like pyramids, they are nearly flat. So they bend. And most roadsters operate with minimal spoke tension. Roadster owners don't much care about spoke tension. They do get a better ride because the wheels are soft.
Trail affects handling. It doesn't do much for ride comfort. Trail has effect only when the bike turns.
My Raliegh DL-1 was comfortable but wobbly feeling up front. Wouldn't consider a front load.Delete
In Ireland I have riden a few pre-WWII roadsters (not Raleigh) where the forks just looked stunningly long, in addition to the slack headtube. Didn't have a tape measurer on me either time, but I keep meaning to come back to the owners and measure those bad boys.Delete
I have owned 2 functional DL1s, and they seemed perfectly happy to carry a bag or basket full of laptop and camera, dangling off the handlebars. Then again I traveled at 12mph on quiet city streets.
Hey Anon 2:12,Delete
I get what you mean when you say "trail has effect only when the bike turns", but to some degree if the bike is moving, it's turning. When the you stand to power over a rise the bike turns subtly back and forth as you lean it side to side, when you countersteer to straiten the wheel from a sidewind, when you trackstand(if you trackstand, and if you do you probably get as big a smile from doing it on your DL1 as I do on mine), even when you take your hands off the bars and steer with your hips as you glide along, trail is working for or against your purposes.
It's really one of the dominant dynamic forces and if you have a bike that works with your preferred style of riding maybe it's because the trail is in the sweet spot for it. That's a big part of "Comfort" the way I define it.
I just finished building up a racy old late 80s Fuji Club frame I picked up. High trail, short stays and top-tube, with a long 120mm stem. 62cm so it's tall which tends to make bikes more stable. I assumed it was going to be super stable and it is, just the opposite of another old race bike of mine with typical late 50s to early 70s low trail road geometry. Low trail bikes gets labelled "squirrely" because of their willingness to change direction and need to be supervised more or less all the time. The high trail bike is said to corner like it's on rails which promises foolproof safety and confidence. That sort of describes those bikes of mine, which is cool until I really need to change direction quickly and precisely.Or I take my hands off the bars.
That's when the low trail bike goes where I want it, neatly and easily and the high trail bike tries to plow along on it's own course. My Raleigh International has the worst high speed shimmy of any nice bike I've ever had, and when you take your hands off the bars you have to constantly steer with your hips as the front wheel noses around hunting for a scent. It's one of my favorite, best handling bikes. It never takes much to put it just where you want it, but you have to know where you want it and keep the "reins taut". And a bike that you know is going to shimmy can't hurt you.
The High Trail Fuji just feels planted and solid, even when it's pointing where you don't want to go. Take your hands off the bars and you get to experience that panicky feeling of giving it a bit of hip to correct your line and having it just keep on heading for the fence. I really like the Fuji but not because of it's willing, intuitive handling. It's for falling out of the sky on steep hills with my hands together by the stem, my arms tucked up under my chest and the wind tugging at my ear hairs. I don't want the shimmy then.
Oh well, I just used a thousand words to say very little.
Technically you are entirely correct. In practice it is much more complicated. I sit still in the saddle. I was taught to ride that way. Once I'm faster than walking speed my 'bars barely move. Next to me is a guy whose 'bars move 2 degrees left and 2 degrees right with every revolution of the pedals. He can't ride a straight line to save his life. IMO he's using his trail quite a bit and mine is largely theoretical. Busy now, more later. It is an interesting point with room for opinion.
Hello again SpinDelete
I do not lean myself or my bike side to side when topping a rise. Why ever would I do such a thing? Leaning would mean lowering and lifting weight for no purpose. As the downward lean is controlled, not just gravity, work is being performed in both directions. Work done that does nothing to move the bike forward. If I lean on a climb it's because I have been reduced to walking speed, where trail matters a lot. It also means I'm tired and have given up on good form. I try not to do that.
I do not countersteer in crosswinds. I keep the bars straight and lean into the wind. Countersteer would mean tire scrub. It would mean wandering a bit around the road and a series of course corrections. Just lean into the wind and get on with it.
You see how this goes. The cleaner you ride the less the necessary mechanics matter. I ride the bike, the bike does not ride me. I have agency, I am in control, and it is up to me to make the wheels go. I will of course notice if the wheels are lovely or inspiring or mechanically interesting. The wheels will go well only if I make them go well. Pursuing mechanical perfection and acquiring lotsa stuff will not make the wheels go well.
Getting the next bike to fix the problem with the last bike never works. The bike was always the smallest part of the problem. Learn to ride and all the bikes go pretty good.
Just for the record I did once own a '71 Colnago Super and I tried to race it. This was mid 80s when an early Nago was old race iron, not collector Grail. 74 head and 50mm rake. I was warned about the squirrels and it was squirelly. A handful but survivable in a road race. I will not forget the crit. I was just clever enough to glue 29mm of Campionato del Mondo to the front wheel. With 75 psi up there I had more rubber on the road than anyone else in the race. I am sure I could have found a line through the corners as fast as what everyone else was doing. Thing was the only choice was to go through the turns in the same arc as the guys with 57mm of trail. The 45mm trail bike would not do what the 57mm trail bikes did. Getting through the turns involved a fair amount of sliding and bumping. I had an old Avocet 20 computer that read in km/h. Through most of the race the first digit was a 5. Approaching the final turn I looked at the clock and saw the first number was a 6. Discretion is the better part of valor. I sat up. Anyone tried to do that on a 40mm trail bike would do radical kinetic realignment of their frame, most likely in the first turn.
Excepting Brompton and cycle trucks (including postal bikes and porteur des journaux) I can't think of any series production bike that ever had low trail. Your International does not count, they made those in every rake and every head angle and put the same stickers on all of them. Not all that many low trail bikes ever existed. There are good reasons for that. Not that many people want to ride a cycle truck, no matter how it's dressed. A bike mfr big enough to employ a mechanical engineer and an attorney is not likely to want to market them to the general public. For people who go out of their way to get them, they're fine. My sweetie has one and she learned it in 5 minutes. Hardly noticed the change. Because she's a good rider. The rider is always more important than the bike.
This is such an interesting experiment. It reminds me of something that Bicycle Quarterly would do. However, a true BQ test would likely pair two equally fit riders on identical bikes, one with low-trail fork, one with mid-trail, trying to drop each other, then swapping bikes midway through the test. By the way, I hope you've made arrangements for a wind tunnel test as well. It will be interesting to see whether your research would prompt Bella Ciao to offer a choice of forks (probably quite a bit of cost involved there), switch to low trail for future production runs, or keep it the way it is.ReplyDelete
And yet all the literature, this from sheldon brown for example ("Trail is the distance from the center of the contact point of the front wheel with the riding surface to the intersection of the steering axis (head tube) with the surface. The trail is a function of the head angle, the fork rake, and the tire diameter. Trail has a major effect on the handling of a bicycle. More trail increases the bicycle's tendency to steer straight ahead. A bicycle with a largish trail dimension will be very stable, and easy to ride "no hands". A bicycle with a smaller trail dimension will be more maneuverable and responsive.") ,maintains that low trail bikes are harder to ride no hands.ReplyDelete
That's only some of the literature - whereas the Bicycle Quarterly gang, for instance, is of the opposite opinion. It's a rather opinion-polarising topic, and my own impression is that individual differences (in one's bodily center of gravity, sense of balance, proprioception, etc.) play a big role in which way low vs high trail feel.Delete
and yet you credit the lo trail with hands free stability.Delete
Yes. I wrote that to me it feels that way. And noted that sensations/preferences in this respect differ.Delete
I can't quite tell from the photos: are the wheels 700c or 650b?ReplyDelete
I have a 90's Trek hybrid and a Brompton; the former I assume is high trail and the latter I believe is low-trail.ReplyDelete
Wheel size obviously explains a ton of the difference in how these bikes feel, but I think that what a low-trail bike feels like is very rarely explained clearly. My understanding is that basically a high-trail bike is one where you don't really steer with your hands, and most turns start at the hips, whereas you use your hands/arms more on the low trail.
That's one of the big differences I notice in my two bikes - I basically lean the Trek to steer it, and I do the same with the Brompton, but my hands are involved in turning the bars/bike a bit more, in addition to leaning it.
Does that jive with what low-trail feels like to you?
I have a German Torpedo brand bike made in 1936. It belonged to my father-in-law. He rode it 1000's of kms up into the 60's, and then until about 1980 it was my main summer bike. It is still roadworthy. It is a handful to say the least. It weighs about 22 kilos, is 2.1 meters long from front tip of front tire to back tip of back tire. One doesn't speak of "riding', but rather of "piloting". It has drop bars and two gears, but you have to stop the bike and get off and get into another gear by untightening the big wing nuts on the rear axle and moving the chain over manually.ReplyDelete
It is solidly in the super-low trail range. It will go over top of anything. It was (and is) used on back roads in rural Finland. Sheldon Brown had one. It is listed in his long list of bikes he had owned. He said It "is a good bike for cobblestones". Sums it up. It ignores cobblestones.
I have seen and rode a few other Finnish and Swedish bikes from the 30's. That all fit the above general disruption.
I would prefer the low trail fork on my Bella Ciao to one it has. Maybe even super low. Do you have any idea what the cost of a different fork would be? Do you think they will make this a real option?ReplyDelete
I think that even if they don't, you can ring them up and ask for one if you do not mind paying for it +shipping.Delete
The Bella Ciao makes a nice test bed for assessing bike handling with different rake forks because of its relatively steep steering angle (for an upright city bike) that reduces “wheel flop” to a tolerable amount. I’ve always hated my father’s Dutch bike’s tendency to lower its front end considerably in tight turns and thus increase steering input by an annoying degree – thanks to Jan Heine, this phenomenon now has a name.ReplyDelete
Tire width should also be factored in when looking at a bike’s front end geometry, as wide tires also increase wheel flop. I have been researching how a front load affects handling on different bikes for quite a while now, and found bikes with narrow tires to be a lot more tolerant in regard to how they handle with a front load. In my experience, trail does not matter all that much (within reason) up to a tire width of about 30-32mm. For example, my Kona Paddy Wagon with 28mm tires (the widest they will accept with fenders) handles great with a front load of up to 8kgs.
Velouria wanders into her kitchen. No leftovers worth heating up and nothing especially exciting in the icebox that could be whipped into something tasty in a jiffy. So she reaches into the cupboard and brings down a can with an interesting label marked "Trail". "May as well see what this is all about" she murmurs brightly to herself as she clamps the can opener onto the rim and starts twisting. The lid lifts as the can spins around revealing... Worms. An effing can of worms.ReplyDelete
Taking a sidelong whiff and eyeing the glistening contents, she decants the mass into a pot and drops it on the cooker, suitably warmed she takes a tentative nibble before drawing a determined breath, throwing her head back and forcing the entire pot down, Korean Noodle Shop Style with a spoon in one hand and the pot handle in the other.
Later, after a lie-down and a Guinness, she clears up the kitchen and washes the dishes. Dropping the empty can in the bin with a quiet "burp", rinses her hands and thinks to herself "went down better than it might", then wonders how hungry she'd have to be to do it again...
You are a brave woman V.
In 1981 I bought a Trek 614 to replace my too-big Schwinn Varsity, which was a bit like going from a 1962 Ford Galaxie to a 1981 Toyota Starlet, a switch I had also recently made.ReplyDelete
With its low trail and long chainstays, the Trek was zippy, responsive and comfortable. I used it for touring, commuting, and everyday riding, and loved it. It was just a tad to small for me though, and when the composite and aluminum 2100s hit the market in 1991 I got one of those and the 614 gathered dust. I sold the 614, a decision I have regretted ever since.
Eventually the 2100 was joined by a Rivendell Atlantis. Both are great bikes in their own ways, but neither scratched the itch left by the missing 614. Recently, however, I took delivery of a low-trail 650B Chapman. The itch no longer troubles me, because my new bike at least as zippy, responsive, and comfortable as the 614 was, plus the fat, supple tires smooth out the ride even more and make gravel roads a less-challenging option.
All that may be too much information just to make my point, which is that a low-trail geometry does all things well — for me, at least.
When I was a kid we would take forks off junker frames, cut the blades off with a hack saw and jam the blades of our Sting Rays down in them. Crazy? Yes! Unsafe? Yes! But it will quickly teach you about trail and head tube angles/Rake!ReplyDelete
Jam them in so the blades actually continue the flow of the original fork and the steering is impossibly slow, rideable, but don't try to change direction to quickly! Jam'em in the other way, so that the result resembles an "S" and the front end get raised up drastically and the steering gets REAL Twitchy! Sometimes I would see kids from the projects with 3 or 4 lengths of fork blades jammed alternately together! Hilarious!! - masmojo
Great title, Hogarth or Stravinsky?ReplyDelete
A bit of both. But I think this one is particularly fitting!Delete
Tom at Spectrum Cycles has a good discussion about the effects of the trailReplyDelete
on bike handling (http://www.spectrum-cycles.com/geometry.php). His comments
seem more or less to agree with your observations.
So cool! Would this make Bella Ciao the first modern low trail city bike?ReplyDelete
Not if you count Brompton. They don't advertise this, but it's super low trail.Delete
I've just gotten back from a week of riding the Brompton on vacation. Was putting 15-30 miles a day of general puttering about plus a few longer rides. The first thing I did when I got back was put a few miles on the custom bike (trail of 42 or so.) So here are some thoughts:ReplyDelete
-The Brompton's trail is a bit lower than I prefer. The combination of small wheels, low trail, wind, and cobblestones make it a bit...loose in the steering. Not bad but bigger wheels and tires were wanted. I'm not sure if this is a factor of wheel size or trail or a combination.
-I tend to go around objects more on the Brompton than the custom.
-I think geompetrical comfort is a variety of factors including tire flotation, mechanical trail, handlebars, and chainstay length. I also like zippy bikes so I prefer shorter chainstays. The trail was ok for Amsterdam but the handlebars and tire size were less than ideal. Combined with the wind it was less than perfectly comfortable. I've actually preferred the Brompton going over hardpack desert to cobblestones.
-I also rode a modern Gazelle which was built like a tank but rode very well. Both were more comfortable set up as city bikes than the Surly I've got back home.
-For a city bike, I'd pretty much go with the old french mixtie set up porteur style, 650b, swept back bars, fat tires and if the trail hit in the upper 30's to low 40's, even better.