what jets to run???

[KYmxracer52]

My brother bought an ESR 330 kit for his 86 R and he's running a Keihin 38 A/S w/ an LRD exhaust. He has it set up for MX w/ the race dome. What jetting do you guys recommend starting out with? I believe it has a 172 main, and I believe a DEG needle. I'm unsure on the Pilot, but do know its around a 55. Seems to do pretty good on top, but bottom to mid is a little sluggish. So much that when it comes in good on top, seems like it hits like a light switch. Hes also running the V Force2 reeds.

[beerock]

I run c-12 race gas,K&n,39mm pwk, cr 250 rad valve, 230 psi, curtis sparks TT pips,br8es plug 52 pilot dgh with a 185 at sea level. nacs said around the same thing. id start here and work your way down, my plugs are a bit rich, but i run my bike that way. Iusually change plugs every ride anyway and after about 5-6 hours its time for a new plug because my bottom end gets a bit sloppy. id rather change a plug then a piston though so i run it a bit rich.


curtis sparks told me that jeff runs a cel needle and cuts down on the pilot to a 50, im running a 52. seems fine, i think a 50 is low but two companies told me the same thing. Id call cnd check,

[dober250R]

55 pilot is huge!!! I have a 40mm carb, bored .080 over, no port work, with stock 250R intake and boyesen reeds. I'm runnin a 48 pilot, 185 main. I'm runnin crappy 94 gas with octane booster right now, but i just found some 110 around town. I'm also runnin the b8's, the b9's foul out on me. I'm runnin 210 pounds also. Do you guys think my pilot is 2 low? sorry to butt in on your post. oh yeah, i'm runnin a full bill's exhaust. u can check out my quad in the open forum, or on the 250R page. A 55 pilot seems a lil big. With jetting that's all you have to do is experiment with different jets and be careful, and read the plugs.

[88350R]

i donno if ne of this will help you, but Allen at CT racing told me to run a 52 and a 190..and mine is a 350pv, ct exhaust, delta reeds, k&N, right now its runin on 114 fuel. ive gotta 38mm...

[methyman]

You can call ESR for jetting recommendations. They will probably tell you like a 50 pilot and 180 main to start and you will have to lean it out from there. My 330 has 178 main with a 50 pilot with the air screw 2 turns out.

[KYmxracer52]

Which needle are you guys running? I believe his is a DEG. Is that abut right?

[zedicus00]

theres a lot more that goes into jetting. im running a 57 pilot 200 main deg needle in midle clip on a ported 300cc kit. 38A/S short body carb. with a BP5ES plug.