I've been holding on to my 99 GS in hopes of finding a descent used GS to put together a track bike. I found a 89 GS track ready with some cool upgrades for $800 (bonus question,$800 worth it?) . My question is how interchangeable are parts between these years? would engine parts be pretty interchangeable? Or suspension? Brakes? and so on. Thanks.
Should be the exact same bike. Everything should be interchangeable.
I agree with syntax, GS is a very iterative design and little has changed over its production life. Should have very limited crossover issues, if any at all.
To me $800 for a dedicated track bike is worth it, totally. If it's in good working order and you're going to soup up your 99 with the parts... sure I'd pay that. A lot of the cost depends on area and your personal limit, however, so that'll always be subject to interpretation.