Today I picked up a bone stock 2009 KLX250s. Now I knew it was going to be lacking some power but after riding it all day i am realizing this thing needs quite a boost. What is the best way to get this baby moving a little bit? I definitely want to get an exhaust but don't know whether to go with just a slip-on or a full. Anything helps and thanks in advance for any replies!

 

I put a jet kit and a Leo Vince slip on. Stock Header. The re-jet and pipe really wake the bike up. I really like my Leo Vince pipe as its all metal inside. Nothing to repack after so many miles. Other than that get a 330 or 351 kit and a pumper carb.

Cheers.

 

THIS. Even without the pumper carb the Big Bore cheapest power to dollar mod you can make.

 

slip on, stage 2 dyno-jet kit...start there.

 

Don't waste your money, go right to big bore 351.

351, exhaust, jet kit, done.

 

What does a big bore 351 run?

 

351 Big Bore Kit $527.45


Plus $175 core charge if you don't send in your cylinder.

 

That sounds pretty reasonable considering the only one I can find online is a 330cc bore kit for $789. Where did you find that 351 at?

 

bill blue is who they are referring to, which is who i need to contact for a kdx snorkel soon as well...

 

By the way thanks everyone for all of the quick replies. You all gave me some good info and now there are definitely some things to consider.

Also, for those of you who have the big bore kit, does it affect the freeway riding in any way, good or bad? And also the fuel efficiency? Since I am going to be riding to work mostly I want to make sure the mileage is still good. I read somewhere that a big bore kit reduced someones mileage to around 40?? Seems way low even with the 351 kit.