'06 cr250r factory float setting to high?

I just got my honda 2 smoke 2 weeks ago! Can't get my jetting correct, plug fouling and very black, smokes.. Typical problems. I've dropped the jetting down to 380 main and 35 pilot air screw 2 1/2 to 3 turns out (big drop) still rich so I dropped the float (it was set correctly according to the manual) 1mm to 8.5mm and it did help but didn't fix it! my elevation is 5800 ft! Reason I feel the float is high: first day I got it, it was loosing a bit of gas out of the overflow while it was in my truck and fouling plugs bad before any adjustments so I did the above and now after the adjustments: after idling for 10 to 15 seconds during a ride (stopped talking...) I can hear the sound of the engine, it change as if the float bowl has been given time to fill while not using much gas? Also if its shut off for even a short few mins, I start it, it smokes excessivly and if I give it throttle right away it'll foul the plug. The Idle does sound lean after the engine has been run hard, again for only a few seconds (it should be a little lean with that pilot and air screw out that far) till the float bowl is given time to overfill? P.S. air screw adjustments don't seem to change much as if the float level is still slightly high.

I'm at 4600 ft and run a 350 main. Temperature is mid 70's now.

Don't know what your temperature is. You are at a higher elevation so air is less dense. Quick guess is your main is too big.

when I first got my 04 250 it too leaked from the overflow if you tilted more than a couple of degrees off center. I thought to myself "this cant be right" it would soak the swingarm and back wheel with gas when riding. I checked the float height it was right according to the manual-7.5mm so I just like you, set it to 8.5mm and now its fine. :confused:

Hi Guys,

I need help. My Dad rides a Honda CR250R 2005.

Its a beauty of a machine, but I need help in tuning and working on it.

Does anybody, anybody knowwhere I can find a manual for the bike?

Please help me guys.:confused:

I dropped down to a 350 lowered the needle 1 notch which put it as low as it would go yesterday did a WOT test and it was lean went up to a 360 raised the needle back up one notch now it looks good at WOT but still rich on the bottom fouled a couple plugs but only after it had been shut off (not for long) it runs great too great power all over sounds good good throttle response I did notice when I put the 350 in I lost some low end power? thanks for the help?

My 04 doesnt have the same stock jetting as yours, but when my bike was new I had to drop the pilot jet several sizes down to clean up the 0-1/4 throttle. Even after that it blubered off the bottom a little. I googled TMX11A, and found a Australian FMX forum where I found a hot tip for the tps mikuni. If you pull back the airboot to expose the back of the carb, there is a small gauze filter covering the air passage for the air screw, The 03 and earlier mikunis dont have this. Remove the gauze filter and put the small bolt back in with some blue lock-tite, after I did this I actually had to go back-up on my pilot by one size! Now my bike runs crisp in the 0-1/4 range, I can putt around on technical singletrack all day long without the bike loading up. MY advice is to remove the small filter before you dial-in the pilot jet size and air screw settings.:confused:

Thats interesting? I know what you're talking about mine is a small screen not gauze I think I'll have to try that sounds like the best answer I've gotten so far? I've seen alot of older carbs that had a plastic plug in the air screw passage maybe I could find one of those? It fouled 2 plugs yesterday and its about to drive me nuts! It defenitly is 0-1/4 throttle where its having issues and if I'm on a straight road slowly rolling on the throttle its real "blubery" (technical dirt biker lingo) till about 1/4 throttle where it instantly clears up and turns into a fire breathing dragon!

I ride the same elevations and had the same issues. I went with a JD Jetting kit which simplified things.

Vforce3 reeds & PC Plat2

My setup with JD jetting kit

6000 ft. Elevation

32.5 Pilot Jet

Red Needle 3rd groove

380 Main

Never fouled a plug yet

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