Small frames: high trail or toe overlap?

[Doug Fattic]

my original post was just asking which would you choose high trail or toe overlap on a frame that HAD to have either one.

If you are making bicycles in some kind of volume – be in 10 or 20 or more – than you can never have toe overlap. It is probable that at least one buyer in that group will hit their front wheel with their foot and go down and possibly get hurt. It is also likely they will see the designer as the one at fault. Every company that makes bicycles in serious numbers sacrifices other variables for toe clearance so they won’t get sued – which could be very expensive even if they did win the lawsuit. If you are making a single bicycle than the question is open for discussion.

[11.4]

If you are making bicycles in some kind of volume – be in 10 or 20 or more – than you can never have toe overlap. It is probable that at least one buyer in that group will hit their front wheel with their foot and go down and possibly get hurt. It is also likely they will see the designer as the one at fault. Every company that makes bicycles in serious numbers sacrifices other variables for toe clearance so they won’t get sued – which could be very expensive even if they did win the lawsuit. If you are making a single bicycle than the question is open for discussion.

Good advice.

[blasdelf]

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.

26" (559mm) wheels should be quite common and useful, if you can source reasonable road tires for them

[Andrew R Stewart]

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.

Richard- With due respect I don't agree. At least with your focus on the head tube aspect of the changes that a smaller front wheel can bring. I sat in on a presentation that Bill Boston gave back at a GEAR rally in the early 80's. His goal was to reduce the reach and far less so the stand over. In selling the Terry line for 15 years (and a few Terryakies that were likely built on the larger bike's jigs and suffered from too much top tube) the issue that sold the bikes was the reach and the stand over was almost never the deal.

It is easy to design and build a frame with a low stand over. And use common components. Getting a shorter top tube (then say 48cm), maintaining toe clearance and non rod brake bike steering is questionable. But as some one else mentioned we build for different markets that have different expectations. My current "market" is my partners and their needs. Not athletic, highly skilled and aggressive riders who tolerate discomfort as a trade off to a faster time.

I also agree that for their time the 540 and 520 wheel sizes were the right ones for these alternative bikes. Today things have changed and the 559 and 571 choices (I can't yet grasp the 584 stuff) offer many options that weren't around 30+ years ago. This "need" to have two wheels of the same size is, IMO, a miss guided one for most riders (how much room can a second tube take up in your bag?). Andy.

[Andrew R Stewart]

I should add and edit my above post.

Edit- The last sentence should have read more like "This "need" to have two wheels of the same size, IMO, is a misguided one for some riders as how much room can a second tube take up in your bag.

Addition- Another aspect of Richard's post that I disagree with is the suggestion that conventional lugs were easily used when a small (say 520) front wheel was speced. Both the ST/DT angle and the HT/DT angles changed by 4-6 degrees. That's a large enough amount to challenge most builders, especially with cast lugs being the standard high end BITD. Fillet brazing hadn't yet come to be accepted by the US public, for the most part (IMO the Schwinn image was still a factor).

In time Hank offered DT lugs with close to right angles for the 520 wheel. But these were not long for the having and economics moved along.

To end this triad I'd say that it was a complete "workaround" of the parts of a bike that offered a different solution for short reach riders. Just more about the components and not the frame. Andy.

[e-RICHIE]

My recollection is different, or maybe I was back in some other day. Framebuilders knew how to make frames with the available parts and did for generations. When folks with no experience, or from other trades, tried to come in through a cracked window, they lacked the ability and training to make these small frames well and/or well designed atmo. Hence the small front wheel thing.

[Gattonero]

By the look of things, TIG or FB seem the best options.

Would be interesting if one of the builders around could post a small (48cm or less) frame design with quotes and angles

[jclay]

My recollection is different, or maybe I was back in some other day. Framebuilders knew how to make frames with the available parts and did for generations. When folks with no experience, or from other trades, tried to come in through a cracked window, they lacked the ability and training to make these small frames well and/or well designed atmo. Hence the small front wheel thing.

"You can have it in any color, as long as its black"

General history suggests to me that the builders made what they made, to the best of their ability, and the riders just lived with whatever tradeoffs existed. It also seems likely that, absent the possibilities born of the Information Age, the cycling population wasn't privy to nearly as much information or breadth of perspective as is common now.

While evolution in any area of human endeavor includes plenty of duds and dead ends, that cracked window let in a lot of thoughtful and creative folks, to the benefit of cycling and cyclists; I'm thinking suspension systems, IC lugs and generally gravitating towards increasing quality of fabrication, never mind composites (which aren't my cup of tea). Some of what has been re-discovered is quite relevant too (fenders, fat tires, different wheel diameters) and has expanded bicycle usage for many. What some newcomers lack in direct experience is sometimes made up for in other ways, and after a while they too have direct experience. Many routes are available for most goals.

The cycling knowledge base is larger, includes input from more perspectives, and is more distributed than ever. I think that's a good thing.

Last time Wichita had a cracked window the infusion of creative types from outside of the mainstream aviation biz turned general aviation (twin and single engine jobs from Cessna, Mooney, Beech, etc.) on its head. In practically no time at all you had aircraft with performance envelopes so vastly superior to anything the majors had It was stupefying. That movement utterly transformed general aviation and had no small impact on commercial and even military aircraft.

In the context of this discussion, or evolution in general, cracked windows are a mighty fine thing.....else the Earth would still be flat with the sun orbiting around it.

[progetto]

Nick told it like it is in quote #47

By the look of things, TIG or FB seem the best options.

Would be interesting if one of the builders around could post a small (48cm or less) frame design with quotes and angles

[e-RICHIE]

Actually - they (the fabricators and manufacturers I had in mind when I replied...) built good small bicycles using sound designs. That was my point. They still would had they not retired, or died. The best thing that has happened since, that has allowed the next in line to make small/short frames, has been the move away from being indentured to lugs.

"You can have it in any color, as long as its black"

General history suggests to me that the builders made what they made, to the best of their ability, and the riders just lived with whatever tradeoffs existed. It also seems likely that, absent the possibilities born of the Information Age, the cycling population wasn't privy to nearly as much information or breadth of perspective as is common now.

While evolution in any area of human endeavor includes plenty of duds and dead ends, that cracked window let in a lot of thoughtful and creative folks, to the benefit of cycling and cyclists; I'm thinking suspension systems, IC lugs and generally gravitating towards increasing quality of fabrication, never mind composites (which aren't my cup of tea). Some of what has been re-discovered is quite relevant too (fenders, fat tires, different wheel diameters) and has expanded bicycle usage for many. What some newcomers lack in direct experience is sometimes made up for in other ways, and after a while they too have direct experience. Many routes are available for most goals.

The cycling knowledge base is larger, includes input from more perspectives, and is more distributed than ever. I think that's a good thing.

Last time Wichita had a cracked window the infusion of creative types from outside of the mainstream aviation biz turned general aviation (twin and single engine jobs from Cessna, Mooney, Beech, etc.) on its head. In practically no time at all you had aircraft with performance envelopes so vastly superior to anything the majors had It was stupefying. That movement utterly transformed general aviation and had no small impact on commercial and even military aircraft.

In the context of this discussion, or evolution in general, cracked windows are a mighty fine thing.....else the Earth would still be flat with the sun orbiting around it.