Sorry but i just can't get my bike to idel. I is a MC250 from '00 main jet is 175 and pilot is now 45, i tried to switch my 38 pilot to the 45, with absolutly no effekt what so ever. It still is way to slow in idel. The idel screw i fully in, stil the same, i can hold it a idel with a realy small amount of gass on the throtle. What to do..
Jetting, again...
- Thread starter Thomas R
- Start date
desertgasser300
Banned
Have you checked your float height? And has the carb ever been rebuilt? May have a small air leak somewhere?
By the way as i read it pilot jet is from idel to about 1/4 throtle, and with my extra spool with the 45 it might be a good idea going back to the 38 one, yes it is a small track and I'm just learning to fly. And since it did not change anything to switch in the first place..
The symptoms you describe indicate that it is pulling over. This is where needle/nozzle is supplying too much fuel at low end and swamps out the idle fuel circuit.
The problem is the needle that is supplied by the factory. Depending on year, this is n1ef or something similar. It is garbage.
With a bike with more time on it the nozzle will wear and make bike very difficult to jet and work well.
If you do rb designs carb mod ron was offering replacement of the nozzle. He is very meticulous and machines a new nozzle....
For folks in North america - Two things I would have at the top of my list are rb designs head work to dial in the squish. Then his carb mod second. The carb mod fixes the inherent insensitivity in the idle circuit.
The head work is, by far, the biggest bang for the buck.
Jeff
The problem is the needle that is supplied by the factory. Depending on year, this is n1ef or something similar. It is garbage.
With a bike with more time on it the nozzle will wear and make bike very difficult to jet and work well.
If you do rb designs carb mod ron was offering replacement of the nozzle. He is very meticulous and machines a new nozzle....
For folks in North america - Two things I would have at the top of my list are rb designs head work to dial in the squish. Then his carb mod second. The carb mod fixes the inherent insensitivity in the idle circuit.
The head work is, by far, the biggest bang for the buck.
Jeff
memphis2857
New member
Go to a 40 pilot and drop your needle one clip then reevaluate. With it being a 15 year old bike the carb probably has lots of wear. How does it run at half throttle?
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He doesn't say what needle he has.... If it is the n1ef, then your suggestions will definitely help... but to fix it he needs a better needle along with something like a 42 pilot... back out his idle screw when switching to new needle etc.
As a side note, The MC comes with a higher compression head so it might not have as bad a squish measurement as the ec model.
Jeff
As a side note, The MC comes with a higher compression head so it might not have as bad a squish measurement as the ec model.
Jeff
CACTUSREID
New member
older bikes do wear the jet nozzle out and make the jetting really tough and different from what you have heard are the standards. I had a few lively discussions with webmaster about a 01 ec 300 that i had years ago. the bike had probably close to 1000 hr's on it, the inside of the carb was trashed, and i had to go super low on the jets to compensate for the fuel going past the needle when it was in the jet nozzle at low throttle positions. One more thing,that my buddy's and i discovered and used with great success was to go from a #7 slide to a #9. way more air getting through at low openings,made everything work much better in the idling and low throttle opening circuits. good luck !
I was aware of the oval needel tube, and it looked round, emphasis on looked. I'm running the N3CJ needel, yes stock is realy bad. The running at 1/2 half throtle is good and the cable is with a bit of slack, it slams the throtle body. And the idel screw lifts the throtle body as it should. The idel is just to low other wise it runs great, well except from some spool but that i can live with, it is a 2 stroke after all.
