Originally Posted by
fuji86
In that case, every bike manufacturer's track frames has different geometry and some are virtually indistinguishable from a road frame, others have totally different geometry within the track frame category. The vintage Fuji road bike I have has a straight top tube, even the atb bike I have is a flatter top tube than what today's designs have incorporated for mtb/atb frames. Both are/remain mutli-gear. And going with different front forks with various rakes and angles is going to change the bike's stance and road manners too.
As for throwing a chain tensioner on one (SS/FG that is), that defeats the concept of a direct drive bike, crank gear wheel to rear gear ? The first tensioner increases chain length, adds weight to the bike, creates an inefficiency in the drive train.
but the OP is talking about buying a high-end frame. high end track frames have track geometry. i agree that there are a lot of FIXED GEAR frames that have very close to road geometry, but those are generally not really high-end frames.
p.s. how straight the top tube of a bike is has
NOTHING to do with geometry.
as for a chain tensioner, it in no way creates inefficiency in the drivetrain, that is a myth. a "direct drive" is a rod-driven bicycle, has nothing to do with bicycles who use chains. the OP has also mentioned that he wants a single speed, NOT a fixed gear. they are two different things; one of which a tensioner is totally acceptable for, the other of which it is not able to be used. furthermore, eccentric hubs are HEAVY. my rear hub plus the tensioner weigh less than a WI eccentric hub would. i also do not have any additional links in my system. the tensioner simply takes up the excess slack in a different way than the eccentric hub does.