Hello, i just picked up a new 2007 klx250s about a month ago. After reading through alot of the threads its been tempting to get into some of the differnet mods. Should i break the bike in first before doing any major modifications? and if not what are the simple free-bee mods i can do.

 

I'd say break it in 1st just to get familiar with it and so that once you do start to mod it up you can see the improvements. You could remove the smog crap but you really don't a get performance gain from that.

 

what I did with mine last year was at 256 miles I ripped the snorkel out (free) and put a K&N filter in it ($40). Instant difference in the way it revs between shifts, ithe rpm's didnt drop as much. @ 500 miles when I changed the oil the 2rd time I put a 13 tooth countershaft sprocket ($15), major improvements on the trails.
Then I ran it hard a fast,