And here I am stuck on huge bicycles wishing there was a viable option for wheels larger than 700c…
really? my road bikes usually have a 62cm top tube, I kinda like having teeny wheels whipping around waaaaay underneath me
36er (though the tire selection may suck dead bunnies through a straw)?
I really like the steamroller or monster truck feeling of big wheels. From a purely aesthetic point of view 36ers are rediculous unless you’re like 7ft tall. I want 27" or something a little bigger with good tire options. Never gonna happen, so I’ll stick with 700c/29" on everything except for long travel mountain bikes, 650b/27.5" is sweet on those.
I think there should be like 5 or 6 different common wheel sizes and they should be proportional to frame size, similar to a 700c on a 56cm frame.
I also want +175mm cranks and frames designed for them to be more common so I can give them a shot.
Maybe I should bring this to the dream bikes thread.
I’d say maybe 32", except the tire selection there sucks as well.
(And is the 8mm difference between 700c & 27" significant?)
Marginal gains at best from what I’ve noticed, I’d like to go another 8mm larger though.
http://zinncycles.com/custom-cranks/
I’ve had this as a possible component around which to design a frame for a long long time
Oh rad! Rough measurements while chasing a toddler around the kitchen shows I should be running 200-205mm cranks.
that’s about what I get too, I think we’re physically similar.
I’m sure someone will chime in with why it’s bad to use cranks that long and why Zinn’s basic theory of crank length is wonky - there was some debate about it a decade or so ago on some other forum, but who knows.
My main concern is that preserving cornering clearance would mean reducing the bb drop to about 45mm. It seems as if that would do some not-awesome stuff to the bike’s handling, right?
wait but to rebut myself this is where your magical slightly larger wheels would come in handy. an od of 675 instead of 622 would let you use 200mm-ish cranks with a 70mm bb drop and not lose cornering clearance, but you’d have to have at least 430mm of chainstay to clear the back of the seat tube, all other things being held equal.
Surely someone has figured out a way to put a 622-42 on a 50cm bike without toe overlap by now?
PVD
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26" rim and tire choices are not encouraging. It’s not just toe overlap, but jacking the ST angle, with all the trickle down from that. Actually stoked to have better choice for smaller riders. Also fine with the 27.5 trickle down parts.
Properly inflated tires are certainly more efficient and more volume is probably going to be more forgiving for getting that part right. I would wager that actual fast people have figured that out or have someone who figures that out for them. For regular joes, having the fudge room that larger volumes allow will deliver a better effecient+comfort) ride, more often, but not faster in absolute terms.
Separate from magic tires. I can’t in good faith recommend Compass tires having ridden them and seen them fail for others. They’re a lot less fast when the bead won’t stay in the rim.
It’s doable, but maybe not in a way that anyone would like. If you put in a long TT and use a very short Pacenti-style stem you might be able to get a decimeter’s worth of extra room before the geometry goes completely to hell. (a 50cm square frame with an 11cm stem can be converted to a 60x50 with a 1cm stem which will look super-funny until a front bag is put on to hide your shame.)
Aka pvd’s allroad bike
I was thinking of Kirk Pacenti, but, yeah, the ego that walks like a man does the same thing with his bicycles.
No?
If your pedal at 6:00 is the same height from the ground and you’re just moving the axis of your cranks up, your ass is the same distance from the ground.
Only real drawback is getting fucky with closing hip angle.
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My ti 29er is this way, with tiny ~30mm BB drop and 200mm cranks
Yeah 6 o’clock is at the same height, but 3 and 9 o’clock are waaay different
Moving around out of the saddle is now much easier because it’s further beneath you while standing on the pedals. Your center of gravity is much higher over the axles, which is part of how folding bikes feel weird.
I’ve got some 190mm square taper Zinn/HSC 130bcd cranks that might be educational for you. I rode ~5k miles with them on a road frame with a 78mm BB drop, so you could totally get away with it on a normal frame.
I have no frame to take such cranks and my current build is using plastic Schrams. 