I have an '09 KLX 250 s with a couple hundred miles on it. I got a KLX 300 exhaust and I want to put it on without re-jetting. Will that be OK? I will get to the re-jetting, but wanted to put the exhaust on right away to get the bike to sound better. Thanks.

 

i put a two bros slip on on my 09 250s without jetting it and it seems to run just fine i havent really riden it that much because i broke my wrist on it. so maybe it will run crappy when i really open her up. I asked 2 local dirtbike shops and they said dont worry about jetting unless your bike doesnt run well with the aftermarket pipe or you want maximum power. so im gonna hold off on jetting for now. just my 2 cents

 

Y'all should be OK, so long as you don't open-up the airbox prior to rejet.