Help!! I have a few Jetting Q's!! Need fast response!!!

[Kyleb15]

Hi I have a 2000 Yz 125? It has a FMF fatty, powercore 2 silencer and a 136 big bore kit. First off, I took it out to my local track about 3 weeks ago and it was snowing. By the time we got there the snow had stopped and it was 40F. I took the bike around the track just to get the groove on again. This was in like 1 st gear, not too fast. So I bring it back to the track after that lap and wipe my goggles off. I try to start the bike and it won't start. So i put another plug in it and off she go's. Well it was running kind out rich and I had a hard time keeping it running, but lasted the day. So, i get it out about a week ago to test out my new spprockets. Take it out in the feild and try to break in the sprokets. Then i tried to do a WOT test run. Imediatly it is'nt real peppy and when i let off the gas it just wanted to die. Mind you it is 50F. It lets out a lot of smoke and does run like a properly jetted bike. I know it is not the top end because it has but 6 hours.

So, when it was 40F it is really rich.
When it is 50, it is better but not right.

I tried RAISING the needle CLIP, but it didnt have nush off and affect.All of my local stores dont have main jets. So, I getting two sizes lower of pilots tommorow.

Currently I am running a 35 Pilot, and a 370 main, with the needle at the 2nd from the top slot. It is going to be 60 tomorrow so I need to get it figured out so i can ride. The plug is a B8ES. If it wore lean it would be whitish but it is dark brown. When it was 40F the plug was black. To me this signals a rich condition, and since it is getting warm I should lean it, right? Please any suggestions!!!!!!!!!!!!!!!!!!!!

 

[Vic]

You will likely have to go leaner across the board with the big bore. For now, I would try raising the clip another notch.

What fuel:oil ratio are you running?

Is the air filter clean and properly oiled?

Are the reeds in good shape?

 

[Kyleb15]

Yep reeds good shape. They are carbon fiber. The airfilter is clean too.I am running 2.5 ounces to a gallon a belray H1R.

 

[Vic]

I would run at least four ounces per gallon (32:1).

50:1 is pretty light on oil, especially for a 125.

Your jetting would be effectively leaner at 32:1, also.

 

[Kyleb15]

Well I got th new scoop now. Went to the chat dump where i ride. It is preety much wide open riding up big huge chat. I lowered the pilot to a 40 and truned the air screw to 1.5 and put in a new plug. I ogt there and man it was running sweeet. Just right on. Lots of power, So i keep riding shut it off then and there. Then one time i shut off and talked to somone. Started bnack up and went riding, then it started not hitting high rpms. It was really flat on the top. So i get off the bike look for any signs of anything. i find the plug about two turns loose. So i tighted it back up and tried it agian. Still it did the same theing. it was running perfect all day. Then it just wouldnt hit high rpms. Aslo there was oil coming from out of the top of the exghsust valve cover. i dont know why it is doing that either. Any suggestions. Sorry for the bad typing but i have to leave in a minute. Please help!!!