32 posts were split to a new topic: Crank Lenght and Fit: Pros and COns
This is basically what everyone said about 29ers, though. And half of cyclists is a LOT of cyclists! Why should everyone from 5ā0" to 7ā tall be on 650b/700c for gravel? Those sizes are only 6% different!
36" is too big, IMO. Too many compromises and only really āfitsā 2% of the population. Theyāre fun as hell, though, and you can easily feel the advantages in traction/rollover ability on a trail.
32 would be great, though. Thereās no real downside and the bigger the wheel, the better, if youāre on rough terrain. How do I know this? Because the US government studied it during WW2 with tractors, aiming to figure out how to save fuel. No, I am not jokingā¦
-Walt
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No doubt there are possibly benefits to be had but youād have to weigh them up against the cons. Two being heavier ( though bikes are hardly heavy these days) and the affect that has on centripetal and gyroscopic affects on wheels and handling dynamics. It would be something that would have to be R&Dād properly.
I say half because 29 wheels already have packaging issues, which have mostly been worked out, but smaller riders end up compromised in their positions to fit a 29 wheel, fork and head tube in the space under their bars. 32 would just mean more people compromised.
Big problem is lumping all gravel into one category. You know yourself gravel can be anything from smooth cracker dust through to chunky double teack and bryond. Horses for courses, so pick your equipment for the intended terrain. Though obviously yourāre not disadvantaged to your roll by using big wheels on smoith terrain. My only go/no go is fit trumps everything, which then affects design and equipment choice. 
Offsets combined with head angle, fork height and wheelsize is an interesting one!
I agree with you on the lower offset forks Walt. It is common in the WC DH racing world to use fork offset and head angle to balance the grip with the rear end and or create more grip on the front tire in corners. In my experience, there is a middle ground which has neither a pushing nor tucking feel in corners.
Iāve tried many combinations on a Fox 40, 36 and Ohlins DH38. My impressions are when the offset is too low and there are some g-outs mid corner then the tire bites and tucks in a bit too much creating a high side situation. With an offset too low, I had to run the fork harder then I would like to combat this. With too much offset the tire pushes wide in corners. Also, with too much offset the front tire doesnāt climb out of a rut or off camber very well. The tire sort of slides back into the rut and gets pushed around by the terrain. It is also harder to recover when the front wheel starts to slide. Here you can see my front tire sliding but controllable. This is with 29ā wheel, 44mm offset Fox 38, 180mm on a 64* head angle.
On a DH fork with 63* head angle I think 48-52mm feels pretty good.
Double crown forks are a lot easier to test and play around with. At one point I had 4 different Fox 40 crowns and 5 Ohlins DH38 crowns. I had one angled 40 crown which was interesting but a pain to use in practice since you had to be so precise with head tube length for them to line up. Iāll dig out some pics of that stuff.
Hereās a pic with 3 different offset crowns on a Fox 36. I settled on 44mm offset with 170mm of travel on a 64* head angle.
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Again, same thing that was said about 29ers.
If youāve ridden a 36er, youāll understand quickly that while the handling is a bit different feeling, gyroscopic effects and handling dynamics work just fine. Itās a bike, just one that rolls over stuff better. If you spin the wheels up to 10,000 RPM, youāre going to have problems. But at bike speeds, no biggie. Ride one sometime and see.
Now, again, 36" causes a lot of problems for normal sized people and fitting suspension and such. 32 would work for a lot of folks without much in the way of compromises (29+ is very close to this size already, but the 3" tire width isnāt that many peopleās cup of tea). It would be relatively trivial to build something that ended up at, say about 31-31.5" diameter with a 2.4" tire. That would fit a lot of extant suspension forks.
Heavy, schmevy. I remember 20 years ago when everyone was saying a 29er couldnāt win a world cup because the wheels were too heavy. It was a ridiculous argument then, and itās ridiculous now, as anyone who has ridden a 20" wheel bike offroad knows right away after they finish picking up their fillings from the side of the trail.
Even custom builders are conservative when it comes right down to it, right? Weāre clinging to some standards (cranks, wheel sizes, seat angles, etc) that for various reasons may or may not make sense.
-Walt
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If you wanted to really test a moto-style front end, youād need a 20mm offset fork (give or take) and a longer reach/zero stem. WAG youād end up with a similar hand position and a little bit longer front center.
Motos have much longer rear ends than mountain bikes, though, so the weight balance would be pretty odd.
Back in the day Keith Bontrager sort of tried this by making low-offset crowns for the (at the time) bolt-on crown Judy forks. I recall the offset being 25 or 30mm but Iām not positive on that. He combined it with a steeper head angle, though, and didnāt lengthen the front end. The idea was to improve traction when cornering but the end result was too scary for OTB reasons.
It would probably be pretty easy to build your own crown for some Fox lowers. If I were extremely bored and didnāt have 3 small children on my hands I might do it. Which is to say Iāll never get to it.
I love the experimenting!
-Walt
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You did see my side comment than bikes are hardly heavy these days?
We have to be to a certain extent because we are trying to sell to a market that has been brain washed into certain mind sets. We coukd design and build bikes that donāt fit into the ānormā but you wonāt sell anything. Look at my mtbās They certainly arenāt out there but do push a little at the edges of doing something a little progressive, though what Im doing geo wise the big companies have started too as well. They ride great, people seem to like what Im doing visually and rave about them after theyāve ridden one but Im not selling any. So you have to kind of make what the market is buying otherwise you are pouring time and money into a bucket with a big hole in it. I work another job because I donāt make enough frames but I believe in the bikes Im making so Ill keep at it. 
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I donāt know, I have been part of at least a few evolutionary changes in bike design that were due in at least some part to custom builders pushing things in interesting new directions, the most obvious being Wesā 29" wheel advocacy and Pacentiās 650b idea (which Iām less enamored of, but thatās another story).
There are actually a lot of weirdos out there who want to ride something wacky and different and I donāt know that marketing to those folks exclusively is a viable business plan, but you can still do weird interesting stuff even if itās just for your own personal satisfaction (and the aforementioned weirdos).
Just off the top of my head:
-29" wheels
-650b wheels
-Fatbikes/plus bikes (with an assist from Surly)
-Alt bars (yeah, yeah, they all existed 100+ years ago, but JJ revived the concept)
-Singlespeeds in general, though this is more garage tinkerers than āframebuildersā per se
-Offroad touring (bikepacking) bikes (again, Surly is a big deal here, though, and this genre is entangled with fatbikes so closely that itās hard to really decide who to credit)
Realistically custom bike building isnāt a viable business for basically anyone anyway, with a handful of exceptions. So IMO thereās not really any reason to worry about trying to fit in with the prevailing trends too much. You can always build people Session copies if theyāre beating down your door for that, of course.
-Walt
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True, but its not until the big brands pick up on the change and push the marketing that the market then accepts it as a good change. A few years ago people were telling me my bikes would never ride wrll and everything was whack. Now a huge number of big brands are making bijes with very similar geo numbers and everyone is loving them. Im hoping thats the cue where the market accepts that what Im offering is a viable alternative.
Sorry to hijack again, 
, this whole business is so intricate and multifaceted. Every part of it is tied into the rest of it. Things like choice of design affects how you market and who your customers are.
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I like to experiment too! My goal is to make my life easier at the cornering grip limit.
I found some pics of the 40 crowns with different offsets. You can see how the steerer is placed in a different spot relative to the stantions. I need to find the angled crowns to show you guys(angled instead of offset).
My personal cornering techniques donāt work very well with shorter stems and longer reaches. They do work better for me in a straight line. I canāt get enough weight over the front wheel to get the grip when the bike is leaned over. Then when I do get the weight over the front for grip I end up loosing traction on the rear tire.
The longer the fork and slacker the head angle then I need a 50mm stem. I can get away with a 40mm stem but have no grip with a 30mm stem. In that video I posted above you can see my flat track cornering style and trying to find the grip on the front tire. Sliding both tires on flat corners gives me a good idea how the offset versus head angle relationship will perform on the trail. If it is working well then I donāt mind when the front steps out because you have more time to correct and almost a second chance before slapping the ground.
I think the low and forward weight of the motor helps get the grip on the front tire on a motorcycle. Sprung/unsprung weight theory as well as an incredible low center of gravity, etcā¦.
I currently have a KTM 300 2t, KTM Freeride 350 4t and a Beta Rev3 2t which all have drastically different steering behavior. My wife and I like the motos but we only do it on the shoulder seasons when riding bikes is cold and slippery.
This was before I started building frames in here.
My wife is on the right working her way through a technical creek bed.
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Whatās the geo on your bikes that is/was different? Are you talking about the full squish bikes? Havenāt you only built 2 or 3 of those?
Keep in mind, when Wes went all in on 29ers, he built a LOT of them and he talked peopleās ears off and he bugged the WTB and White Brothers (now MRP) guys incessantly. Itās not like he just built himself or his buddy a bike and waited for the world to notice.
-Walt
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I think motos tend to be pretty close to 50/50 weight distro when youāre up on the pegs, but I havenāt ever spent the time to check. Certainly more balanced than most mountain bikes (and much lower COG, which is another reason Iām a short crank/low BB advocate).
Sadly my moto stable went from 5 down to zero when I met my wife. I do live somewhere with a lot of motorized trail access so maybe Iād get back into it someday, but to be honest between skis and bikes and kids itās not like Iām swimming in extra time.
-Walt
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Iāve been pushing the longer reach, ultra short stem and moderate head angles as opposed to the rage of long, low, slack. You get a benefit of the longer wheelbase the slack head angles gave but a better weight balance and a bike that still steered well at slow speeds and flatter ground. I wasnāt the only one as there were a few others advocating the same thing. PVD and Sam Wittingham being two. Though PVD was extreme and I donāt agree with his short chainstay length ideas. Iām more in line with what Sam advocates. Iāve explained it a couple times now.
Iāve built four suspension bikes. Iām not sitting on my hands waiting for the market to come to me. I have two guys riding for me. Iāve booked a booth at Made to get out to the wider world, a much bigger market than the insular one we have here. Iāve booked our local show in June, which ironically looks like will cost more than going to Portland for a week. Iāve had conversations with Pinkbike about a possible review in the future. Iām currently ordering materials to make a batch of 10 frames which will include customs butted and shaped tubes from Columbus. These will be demos and some for sale and a review bike or two. Iām had my bike reviewed in a local mag and another one hassling me for a review bike. Iāve all ready been in a bunch of Pinkbike and Radivist postings. Im pushing hard everyday. I donāt expect everyone to suddenly just start buying because Iāve got a nice paint job. Itās definitely not like Iāve just built a couple bikes and hope they might sell. Maybe, just maybe Iām making something that nobody wants and if at the end of the day thatās what it is then so be it. The feed back that I get from people who see and ride them is to keep going, so I will. No shortcuts.
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Yeah, the equivalent of what Wes did would be to get RS to make you a run of 20mm offset forks (or have some crowns made and swap the lowers) and design around them and then build a few hundred for all the hardcore locals or something. In other words, something really out there and different, not a degree of angle here or there.
Wes was also TIG welding and doing bikes pretty quick/efficiently (ie, he could when motivated to do so accomplish the Carl Strong ābuild a simple frame in one dayā minimum threshold). The slower you move, the harder it is to get any traction on interesting ideas. The selling point of fillet is generally the look, and the people that want the fillet look usually arenāt the same crowd as the enduro bros.
-Walt
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Im not doing small offset forks though. My approach uses standard forks. Im not trying to revolutionise or change the landscape or sell a million bikes and Im not interested in selling āproject bikesā. Justcsell enough to pay for my living expenses and go ride some different places. . ā¦and Iāll stick with brazing because ultimately it makes for a better structure that handles stress better. Call me insane, naive, stupid, whatever this is my chosen path that has come from a lot of trial and error.
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Tig, lugs, fillet, and wrapping and vacuum bagging all make joints that are just fine. Done properly none of them are going to fail so from a performance standpoint itās irrelevant.
Like I said, fillet is super cool. But if a frame takes 40 hours itās just not viable except for the art bike market.
-Walt
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I donāt disagree with the time thing. It is more labour intensive but I can build a lighter steel frame that will last with fillets that wonāt with TIG.
I donāt think thatās the case, but ok. High end air hardening tubing isnāt arguably even safe to fillet braze if youāre trying to use thin/light gauge stuff. I have a hard time imagining the 150g of bronze could be made up for with lighter tubes even if fillet was somehow superior mechanically.
Agree to disagree, I guess.
I got done chasing grams a long time ago regardless. If you want to build light full squish bikes with solo framebuilder level technology, aluminum is the way to go for sure. If youāre doing steel youāre pretty much not competitive on weight no matter what.
-W
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I donāt doubt your expertise. Iām not using ultra thin tubing but I know I can run a slightly thinner wall with fillet than I can with TIG and with the shape and size of the filler and the lack of a HAZ I can build a lighter structure that will be far less prone to the constant parade of TIG repairs Iāve had to fix on other brands over the last ten years. The thinner walls make for a bike that feels great on the trail, and yes you can feel the difference, and Iāve ended up with a 160mm travel enduro frame weighing in at a litle over 4kg with a piggy back air shock. I reckon I m doing ok in getting the weight of the bikes down and being built to last. These arenāt just hammered together with basic materials. Thereās been at least a couple thousand hours in design, modelling, fea, consultation, bench testing, real world testing, failures and refinements.
Appreciate the input though. I have been taking notes for research. 
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@anon91558591 Can you expand on this comment? Fillet brazing is essentially an archaic process everywhere but the frame building world so it is hard to piece together information like this.
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