Originally Posted by psychsurf
XT600 forks are 41mm, but they taper down below upper triple
great idea to compile info, pscyhsurf. this is a very late reply but i just picked up a pair of XT600 forks from an 80s model and there is no tapering, just 41mm the length of the stancheons. this will help as there is a fair bit of adjustment possible before the forks hit the handlebars. possibly the tapering forks are from a later model xt600? i heard they changed in the 1990s...
these should be a great fit and just slide into the SV triple clamps so no messing around with steering locks, instrumentation etc.
i'll need to confirm but it looks as though the stock SV650 axle will work in the XT forks which would be a bonus.
there are various suzuki 1000cc front discs that are 320mm and will bolt on the SV hub, so all i'll need to do is grab one of those then a complete front brake caliper, brake line and lever etc and rig up a caliper adapter plate to space it correctly for the larger disc.
the front should go up by three inches or so for extra clearance, which should balance out nicely will the 90s model ZXR rear shock which is an inch longer than the SV650 so should kick the rear up about the same amount. or just get a set of dog bones that will kick up the rear instead.
at this stage will just fit a high profile front tyre to take it a bit closer to the diameter of a 19" front wheel. but i do have an old RM250 21 inch one lying around. this has the same 20mm axle as the SV650 so shouldn't be tricky to fit.
and some preliminary measurements show a honda transalp rear wheel could be easily adapted (and i can get one for just $100). the only tricky bit looks to be the rear disc is too big for the SV650 but the transalp has the same disc bolt hole pattern as an XR400 rear disc which is 220mm like the SV. too easy!
just thought i'd mention this in case anyone is looking at spoked wheels. if so, other 21" front wheels with a 20mm axle diameter are the WR250F, WR450F, YZ250F, YZ450F and early RM250s. all have the same bolt hole pattern and the cheap way to put a bigger disc on is the 310mm DRZ400SM front disc with the correct bolt hole pattern, and under $150 new on Fleabay.
it would be interesting to get hold of a wrecked transalp actually. the forks would slide straight in, you'd still have twin discs up front....