Small frames: high trail or toe overlap?

[Gattonero]

On a road bike or s/sp with freewheel isn't a big deal, worst case scenario you pedal back a little.
On a fixed-cog is a bit of a pain. But that is the punishment for riding fixed-cog outside the track
Mudguards are a different story, they may be a real necessity for a use that is not only "commuter". And toe-overlap with mudguards is an unfair nuisance.

[blasdelf]

That graphic makes my head hurt atmo. The 5 degree hypothetical change is mad painful.

did you not read anything around the graphic?

[e-RICHIE]

Some posts should be an escape valve from this nonsense, not a reinforcement of it atmo...

did you not read anything around the graphic?

[11.4]

Some posts should be an escape valve from this nonsense, not a reinforcement of it atmo...

Damn right. It's time to start a unicycle thread.

[Zimmermanbicycle]

It's time to start a low trail, toe overlap,disc brake debate unicycle thread

Damn right. It's time to start a unicycle thread.

[Doug Fattic]

The most likely 2nd frame someone will build is for a female companion. At least that is what many of my framebuilding class students say. Get it right and she will love you more and support your future framebuilding ambitions. Get it wrong and there will be bad consequences all around. Fortunately for everyone’s future happiness, I’m here to give you advice about how to design her frame if she is shorter than the average American women’s height of 5’ 4” (163 cm)! And my advice doesn’t include ignoring toe overlap.

Lets be realistic, it’s unlikely a framebuilder’s women knows how (or wants) to ride in a pack fast so making her a racing bicycle (where speed considerations are more important than comfort) doesn’t make any sense. You are lucky if she wants to ride at all and it’s up to you to increase those chances. If you copy store model designs you are starting out wrong. Those companies want as much consistency as possible across all sizes for profit savings and don’t want to get sued because somebody got hurt when their foot hit a 700C front wheel. Their goals shouldn’t be your goals. Instead, your job will be to build her a frame based on her most comfortable/efficient position (with probably the most emphasis on comfort).

Most likely this means her drop bars (if that is her choice) will be near the height of her saddle to take pressure off her crotch. Her seat should be set back far enough so she is balanced over her pedals taking pressure off of her hands. You can tell this when you have her barely lift her hands off the bars/hoods and she doesn’t have to strain to hold that position. Most likely this requires a shallow seat angle (around 72º using a setback seatpost) and a fairly short top tube length to get approximately a 45º back angle with arms extending out at 90º. This amount of setback and top tube length will lead to serious toe overlap even with a 72º head angle. That is why I strongly push for using smaller wheels on smaller frames for normal (as in not racer) riders. Don’t expect her to turn by leaning unless she is fast. She will blame you if overlap causes problems.

Put her on a typical small size production frame with a steep seat angle and then raise her handlebars up so she is comfortable and she will look and feel like she has been shot in the butt with the seatpost. So make her a frame better than what you could buy. Bring her handlebars up high enough to make her crotch happy, move her seat back far enough to make her hands happy (so they don’t have to support her weight) and don’t make her unhappy with toe overlap that might make her crash. This isn't a complicated formula but if she is small it probably means you need smaller than 700C wheels to make it work.

It is possible she is one of those that wants to ride just millimeters off of your swiftly moving rear wheel in which case this advice doesn’t directly apply. But I’m betting most partners want to look around instead of just down at your back wheel.

[crumpton]

i successfully put 700c wheels under a 4'9" women and i'd do it again. While it does have the shortest FC i've done at 560, the 71.5 HTA and 50mm rake give a great 60mm trail and super handling for Norma.

As for toe overlap, you know people tend to scale to their own dimensions for the most part. What I mean is a 4'9" women generally has a very small foot like in Norma's case, a euro 36 along with a custom 160mm crankset. She has no toe overlap.

[Mike Mcdermid]

im going to have to get it out again arent i

POW

https://www.kickstarter.com/projects...universal-bike

KUNG FU CHICKEN

[Craig Ryan]

I don't think a small frame has anything to do with gender.

[e-RICHIE]

Anything down to a 47cm c-t is no problem designing or making. Smaller
than that and they can go to a custom builder and take their chances atmo.

[MrkiMedo]

there is a series of youtube videos about designing frames and small ones in particular by framebuilderess Georgena Terry. Here is the first part:



She also builds small bikes with normal 700c wheel at back and small wheel in front:

Designing a bike around a 24" bicycle wheelGeorgena Terry

[Andrew R Stewart]

Despite the fact that a smaller front wheel (as in Terry or Boston) has been a successful solution for thousands of riders there is a strong resistance to it in many levels of bicycling. Andy.

[e-RICHIE]

Let's be honest; the small front wheel "thing" (sorry, but it was a thing atmo...) from the 70s and 80s was due to the fact that some builders, still using conventional lugs, could not figure out how to forge ahead and make frames without doing complete workarounds on the parts. Rather than think critically, they reduced the length of the fork blades in order to expand the lower end of the head tube - thus giving them a fighting chance to use the material/process they were indentured to. It was charming in an ass-backwards way atmo.

[Vancouverdave]

When I worked at a shop that sold Terry and Bridgestone in the 80's, we used to call the import 24" front wheel bikes "Terryyakis."

David Feldman

[Michael Gordon]

Let us not forget the short lived 69er mtb's! 29" in front / 26" in back. Did they even last a year? Goofy!

[Gattonero]

Despite the fact that a smaller front wheel (as in Terry or Boston) has been a successful solution for thousands of riders there is a strong resistance to it in many levels of bicycling. Andy.

Indeed.
What's the point for some riders using 700c and 50/34 + 12-30 for normal rides without much climb?? I don't get it!

[Doug Fattic]

It has got to be said that the same logic used against Georgina Terry’s 24” front wheel choice (the limitation of yesterday’s fabrication and parts possibilites) can be used against specing only 700c wheels on small frames. Back when she borrowed Bill Boston’s solution to little frame issues, 24” was the most common wheel size smaller than 700C (in the States anyway). Now days we can chose from a greater variety of MTB, 650C and 650B rims/tires. These on a small frame look normal (often more normal than bigger wheels) unlike the oddity of a 27”/24” combination. Depending on the application, they all work fine and solve big wheel problems on small frames.

A true custom frame should be primarily based on a person’s seat/handlebar/pedal relationship. 700C wheels may work for some small riders but it isn’t always the best solution for everyone if the designer has an open mind and starts with a blank sheet of paper. There is no reason to be stuck with the limitation of yesterday’s one option with today’s expanded possibilities.

Another consideration that is very important to me besides what works best mechanically is what looks right aesthetically. 559 or 571 (and sometimes 584) tires provide a little more head tube length for the top and down tube to fit onto and don’t require as much top tube slope to give straddle clearance. They make the entire bicycle look more proportional.

Keep in mind that my alternative wheel recommendations (actually they should be called middle size since they aren’t that small) on small frames are based around a recreational rider’s needs (whether they are in shape or not) on a conventional road bicycle. Racer types like a longer lower cockpit that eliminates some small frame issues. In fact I often think this division of opinion on acceptable toe overlap is based on whether one is a racer type or not.

[11.4]

In fact I often think this division of opinion on acceptable toe overlap is based on whether one is a racer type or not.

This is exactly the difference. eR pointed that difference out early on.

I'm a racer. I'm a trackie. I ride small frames. I could probably go to a 650 frame and have a little more flexibility in the geometry but frankly, I like a short head tube, slammed stem, a fair amount of drop from saddle to bars, and a long reach. My bottom bracket to saddle top distance is 707 mm so I'm not exactly undersizing the frame to get a look or a fit. I've always had toeclip overlap (see how long I've had it if I have to call it that?). Every new rider I've been with, male or female, serious or casual, has cussed out the first frame they rode with toe overlap, but once they learned a little, it was like learning to duck when you step into a car.

I am happy to concede that there are clients for Gatty or for Doug that might want to avoid overlap. They probably have other preferences in steering, top tube height, and other dimensions -- if they were aware of those preferences -- that made a frame easier to ride. In the end, you end up with a Schwinn. But I have no problem if someone builds a Schwinn for a rider who wants it; in fact, I'd prefer it to someone who builds a weird trapezoid to fit someone with a bizarre self-invented sense of bike fit. I likely won't spent a lot of time looking in that direction for my next custom frame, but others will. That's why it's a free market. I'm glad eR won't head that direction because his frames have a special look and style that stands out long before they're close enough to read the decals.

What are we arguing? Two different design styles for two different communities of buyers? What's so hard about that? I'd rather be arguing about ... damn, we already discussed toe overlap.

[jclay]

Curt answered the OPs Q straight away, and as far as this tangential discussion is concerned, for my money, Doug's putting the darts squarely in the bullseye. The comments about the different needs of commuting, and by extension other types of non-road racing cycling, were also squarely on the mark.

The diagram was a useful illustration; the author wasn't suggesting the use of the angles in the model, they were simply for illustrative purposes.

[fpavao]

As the OP on this thread, sorry for my absence. I had a busted keyboard and writing with some keys missing is a pain in the ass. Now it's fixed finally.

I've read all the replies and thanks all for the inputs. But my original post was just asking which would you choose high trail or toe overlap on a frame that HAD to have either one.

You see, 650 wheels are not common in Brazil, and for someone to buy one, it would cost about the value of the frame itself, or maybe the rider could try to look for an old one but that's pretty difficult to come across. Forks for anything smaller than 700 (for road bikes) are also very rare, and I don't make forks because they would have a final cost exceeding the frames I make, in account of import taxes and whatnot.

I'm designing and building for a market that still uses crappy old ten speeds as fixed gear conversions and parts are mostly imported from china. So price for the customer is a huge deal.

But thanks for all the replies and time spent here. I've learned a thing or two (: