@Frankster I think the general idea of the USD forks was to reduce the unsprung weight and add a bit more stiffness. That said the cbr250rr and others have done very well with standard forks. For a drag bike, I can not see any real advantage. Running lighter RWU forks just might help you.
How can a heavy steel pipe reduce unsprung weight over an alloy tube? I have never weighed any but the alloy sliders always feel lighter to hold than steel legs. Fashion fads to sell more bikes?
I've wondered the same and I do actually have sets of conventional and USD forks apart at the moment, so I'll weigh some uppers and lowers. It won't be a truly apples:apples comparison as there's years between the manufacture, but 96 YZF600 RWU -v- 2006 ZX6R USD should be relatable. One thing is that earlier ZX6R RWU forks were 46mm upper stanchions for rigidity, whereas the USD are 41mm lower stanchion so it would seem that for 'equivalent' rigidity USD forks can be thinner
Thanks for that, I have learned something today. I will never ride hard enough to warrant the extra rigidity of a USD fork so am happy to continue with the RWU forks.
If anyone has a ZZR250 bike or front end can you PM me or post the dimensions of everything (fork size, triple tree length, centre to centre etc) please. Thanks
I remember you telling me when the first USD fork was used on a bike when we were discussing MotoGP suspension a few years back. When was it again?