tseck1
Member
Hi,
Does anyone know how this option affects the geometry? I am looking at a 56cm Vamoots CR, but would like a taller headtube to decrease the saddle->handlebar drop. I am wondering if any other geometry numbers (other than HT length) would be impacted, and if so, which ones. I'd think the top tube angle might steepen a bit, but not sure.
Any help is appreciated...
Thanks!
29ner
Member
Not sure what a 'top tube angle' is. The head tube angle? That would not change unless you spec'd it. An angle is an angle no matter the length of any tube.....now the reach will change - but so imperceptible that it would be virtually impossible to feel (in the confines of a bike and with the thinking that your new head tube spec is a centimeter and not a foot). Any reach issues could be 'fixed' easily with a slight fore/aft of the saddle and/or stem.
Moots will either cut or spec 'the size up' head tube and postion it on their jig with the head tube angle required.
tseck1
Member
I was referring to the top tube slope...the stock 56 has a TT slope of 6.7 degrees. This could certainly stay constant with a longer headtube, however that would mean the headtube would extension about the top tube would be rather dramatic at roughly 3cm (which may very well be the case). Just trying to determine what the realities are.
tseck1,
If I am not mistaken, that is the fact. When specing a size up on a head tube, nothing else changes except the head tube length, so it does in fact extend above the top tube more than the "standard" size head tube. If you're wanting a top tube to move up to increase the slope and come closer to the top of the head tube, you would then be in the realm of custom since Moots would have to change their jigs.
Gents,
Correct, the head tube would protrude more above the TT in this case. Everything else would remain the same.
We do keep the protrusion to a maximum of 3cm above the TT....it's just not good build principals to go longer without going custom and bringing the TT up the headtube....for a couple of reasons:
1. The further the head tube sticks out above the TT the more it wants to warp during welding. Not good for headset function...
2. It just plain looks bad. If the rider needs more than that we'd go custom to keep the warping to a minimum and keep the aesthetics in check.
Thanks,
Jon@Moots
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