Hey Guys,
I just picked up a 07 KLX250 with Bill Blue 351 and TM33. Bike has a FMF exhaust and four 1/4" inch holes drilled in the air box, I assume the snorkel is stock. I have a few questions that I am hoping someone can help me with. What is the optimal airbox mod on these bikes? Also, the bike was running really lean down low when I got it. I ended up drilling the pilot jet out with a .5mm bit. It is a lot better now but still a bit lean. Idle hangs just a tad. There is also a small stumble with low throttle openings, although it doesnt happen very often. My carb is currently at:
40P drilled out to .5mm which I think would be a 50.
135M
5FP96 Needle
Clip is in second position from bottom.

How do these settings look? What is the standard jetting most run with the Bill Blue setup?

I know with the mixture screw on other TM/VM carbs in is rich. The 33 is opposite right?

Thanks guys!

 

You paid Bill the big bucks, I hope you went to the man who would know the big bore and the modified carb characteristics best? That would be my first "stop" in this case. Of course it won't hurt to hit here too.

 

bandit88, Bill won't mind that you didn't purchase the carb and BB from him and he is certainly the foremost authority on the use of his products.

 

Thanks, I will probably give him a call tomorrow then. Been riding around some more and have noticed that it is usually hard to get the bike into first from neutral. Shifts into first fine when coming from second. Is that just a quirk of this tranmission or is something off?

 

Also bandit88, I'm not sure why you drilled the pilot jet as it only controls fueling at idle, decel, transition to needle, and low load/low throttle/high RPM ops.. Such as "cruising" at 3500 rpm in second gear with the throttle just cracked open.. Perhaps you should wait on any further "mods" before talking to Bill.. The difference you feel is likely a richer transition to "needle ops" while throttling up from below 3K..Could be that what you actually need doesn't involve the pilot system at all - For instance, it could be accelerator pump timing,duration, (function).. Caveat: My experience is strictly with the CVK..

 

Bill just jetted & modified my TM33 pumper carb, set up for my new 351, stock exhaust & stock airbox. Pilot 42.5 & Main 142.5 @ 600ft, not sure of needle position. A bit rich and wouldn't rev above 1/2 throttle. Switched to my KDX snorkle and runs strong. Slight off/on throttle hesitation I have to work on but otherwise I love it. Has anyone mentioned what a great guy Bill is lately? Well kudos to him again! Haven't spoke to Bill about the off/on throttle issue yet as I am having too much fun with the newfound power. Next year the Q4 and I think I'll be done.

 

Thanks,
I will start with that jetting. I am finding out that the previous was a moron, as usual with the bikes I get. Air system was partially removed, but not all the way. Cylinder is actually a Kustom Kraft 330. Jetting was too lean, gearing was different than what he told me, and a few other small things. At least the bike is in good shape and nothing is broken haha. Jets will be in soon, bought a second rear wheel, still deciding on what tires I should get for the street, thinking BT45s. I prefer a total dirt tire for off road.