Bike is an '07 KLX250S. I'm going to mod the intake by removing the lid and plan on purchasing a Two Bros slip-on for it. Can someone link me to the correct part number? I was looking on DynoJet's website and I saw the kit only for '09 models, will it work on an '07? Do I need a stage 1 or 2? I'm new to this whole re-jetting thing so any help at all is greatly appreciated.

Oh, and I tried searching and couldn't find anything.

 

Okay, I just search a little bit more and found out that our bikes use the KLX300 kit.

... but how do I know which 'stage' I need? ... and how do I know which needles to use?

 

The KLX300R Stage 2 kit. It comes with only one neeedle.
This is the link.
http://www.dynojet.com/pdf/2206.pdf

 

Alright, thanks for the link!

Is it hard to drill the carb?

 

no, it's easy. it's plastic as in the slide drilling. it's all cake if you use the illustrated instructions posted on this website. or, search yahoo for hmf engineering klx250s and it will bring them up. follow them and it's a breeze. adjust your main jet to your altitude. like they said, buy the 300 kit. the '09 kit is watered down and will not make the power of the 300 kit. the needles are different with the '09 needle not being as aggressively tapered as the 300's.

 

I appreciate the information!

So everything I need to re-jet my carb comes in the box? I know I'm seeming redundant, but I want to make sure I get everything I need before I start pulling the carb out.

 

What he said, though no one's actually proven the performance difference. In theory it's better...but that's for another thread. Looking back I would've ordered the 300 kit, just to be sure. Get that one.

Seriously, the hardest part about jetting? Getting the carb in and out.

 

true about the carb removal/installation. in regards to the power claim, I'm comparing what dynojet has posted on their website. the '09 kit makes less power gains on the 250S than the 300 kit does on the 300R. I realize they're different bikes, but I know which one I'd buy again; especially since the 300 kit fits the 250S.

 

That statement is correct.

Is it possible to us the jets from the 09 250 kit and use the needle from the 300 kit together? We know the needles are different, what about the jets?

I wonder if you could just order the 300 dynojet needle. I would love to go dyno the bike and compare and really see what the difference is. Do a couple tests, run out to the lot, change needles real quick, do some more tests.

 

If you can just order the needle I'll take one, but I don't think you can. Anyone?