can anyone tell me of all or at least some of the different types of exhaust there is out there for a 98 gs500. and if possible the price ranges.
another question whats the difference between a slip on exhaust and putting a whole new one on? thanks

made specifically for GS:
Cobra makes a slip on-cut pipe in front of muffler per their directions and clamp this on. not necessary to rejet carbs but helps. about $150 good for sound only-no performance benefit.

Vance & Hines still makes a full system-replace everything, probably needs better air filter and definitely needs carbs rejetted to run right (wont run decently even without it). costs about $280+ for system alone. performance benefit!

Yoshimura, Hindle, etc USED to make full systems and can sometimes be found used-same as above.

I think Nikko still makes full system, same as V&H in terms of jetting, etc.

There are other full systems available though UK distribution channels: Remus, Motad, etc..expect to pay $700+ for full system and needs attention as V&H above.

so what do you think Im looking to spend If I go with V&H? for the exhaust and the jet kit?how much is the jet kit alone and do I need to put on exhaust to make the bike ride right without perf exhaust on and just the jet kit?

V&H will run maybe $280, jet kit about $90 (or just buy the individual mains and pilots for $5 each-need 2 each-at dealer). You'll have to search past posts (or check my site) for jetting formula based on K&N filter (airbox replacement, not in airbox) and exhaust. Airfilter runs somewhere around $35 I think...Im guessing on that one though. Its reuseable too.

A dynojet kit will actually run about $80.00. The K&N air filter is closer to $50.00 this is for the stock airbox replacement.

 -Anti

what web site do you recommend I buy the dyno jet kit for?   I dont exactly know what you mean by the air filter thing, please explain.  Im completely new at this perf part thing.