Can someone tell me if all the main parts needed to SM my 426 are pretty much the same from '99 models onwards?? The same goes for 400/450 and YZ stuff too. I keep coming across stuff on Ebay, such as 320mm front discs, caliper brackets, chains, wheels etc, for models across the board, but I'm uncertain as to whether the YZ/WR 400/426/450 models and years are all cool to use the same stuff on??? The main reason I ask is that I've had problems with my '02 WR426F. I ordered a DEP Enduro Pipe for it, but it didn\'t fit (bracket was a couple of Centimetre's out). Both myself and the dealer assumed it was a fault and a one-off. I then asked for another one (but a YZ pipe instead as the WR pipe didn't really have as much power/noise as I wanted) and it had exactly the same problem!!!! We concluded that because my WR is such a late model (reg'd 04, and they stopped producing them in late '02) it may have a WR450 frame. Either way the frame spec seems different than a regular '02 WR. With this in mind, I figure that I just might have all sorts of probs if the parts that I need have not been manufactured to fit all WR/YZ's (depending on which bids I win!!) The wheels aren't really an issue as I'm having these rebuilt - but obviously my frame is different. Are such things as brakes spindles, bar clamps, chain lengths etc etc homologous on all models? Any advice would be well appreciated as I really want to get moving on the conversion pretty soon!! Cheers, Riffton.