Gosh I'm frustrated...

[jeffd]

Originally Posted by roostafish

LTR's Jetting kit is not a cure all end all. It is that magic needle that, once you find out the right brass, will make you one happy camper. It's a starting point for where you ride. I have the LTR jetting kit in my 300 and started where you are. I ride in the 500 to 4000 foot level, and my bike runs great from the valley to the peak. I will say it took a while for me to get it right, and I may still fiddle. I'll explain in a minute. Bottom line, you're too rich. Go to that 42, lean the needle out another position, leave the main alone for a while, that probably won't matter unless you are riding on roads wide open all the time. Anyway do all that, but here's the key. Your air screw has a LOT to do with the way the bike runs at low throttle openings.
Now my explanation of my further fiddling. I'm running a 45 right now, and I'm 3 full turns out on my airscrew, which is screwy, but my bike runs AWESOME! It has better throttle response than you can imagine. There is no drool from the silencer, and there's a faint brown ring at the exhaust tip at the end of a ride. That said, I may put in the 42 in search of going to a more standard 1.5 to 2 turns out on the airscrew.

FYI - Les told me that this carb is designed to go up to 3 turns out on the air screw - so you being there isn't "screwy". If I were you, I wouldn't mess with perfection and just leave it. It seems to run better that way... (it used to be my bike...)

The stock keihin is way too finicky on the pilot circuit - Ron at RB-Designs modifies the carb internally to make it very, very happy. I rode Magellan's bike with his carb mods - it was very clean all the way through..

jeff

[GMP]

I suspect tolerances/minor flaws in the carb casting are coming into play in a lot of these cases, in addition to the nozzle wear in older bikes. I have seen PWKs with slight flashing on the nozzle. My particular bike/carb runs just perfect, great power and milage. Others have issues. I would have the carb done by Ron.

You should try jetting a Husky WR250 with the Mikuni TMX, now thats touchy.

[widebear]

I would'nt worry to much about the drool but concentrate on how your plug looks and how the bike runs. A lot of the synthetic oils dont burn completly at the temps we run so a little drool can be expected. My buddy has a new Husky 250 and it drooled like crazy till he changed to a fmf silencer, L.O.L. he's still trying to jet that Mikuni but at least his silencer is drool free.

[ggrider]

I installed the LTR kit from my 300 into the MC250, noticed immediately the deceleration was much slower than the stock needle (RPMs stayed higher longer when throttle closed) Same situation with the 300 too, must be the characteristic of the needle.

Still too rich off idle so I switched to the 42 pilot from a 45 with the needle clip at the 2nd notch from top with screw 2 turns out, the bike rips, absolutely perfect in cooler ambient temps with very slight spooge using 36:1 Mobil1...bought a case of Mobil1 after hearing they discontinued making it after August 31st.

Definitely will send the carb and head to Ron when the snow flies around here.