Race Cam with VM20

curtie94

Member
Hey I bet this has been discussed before, but I picked up a bearing race cam for my S65 and I also got a Mikuni VM20. I have a 88cc High compression top end installed.

I have a 15 pilot jet and a 125 main installed right now.

It seems to run decent at idle and off idle pilot screw at 2 1/4 turns out.

I have the needle clip full lean.

My issue is I can't ride it right now since there is ice on the roads, should be warm enough on monday to take it for a spin. but on the center stand when I rev the throttle from closed to wot I get a hard bog and it will stall, choke makes it worse so it must be running rich. But it bogs before I even get to full throttle. Could my main jet be too big? Should I try a 120?

It runs worse when I move the needle clip up even 1 slot.

Another thing I tried is moving the cam 1 tooth down since it either sits 1/2 a tooth up or down it doesn't sit spot on. It helped but still bogs, sounds healthier though.


I checked my ignition timing and it is good.


So I'm running a 88cc top end, 70cc head (new). Bearing Race Cam. VM20 Carb with a port matched intake. No air leaks.

Carb settings:

15 pilot
Needle clip full lean
125 Main
Pilot screw 2 1/4 out

It just seems to run rich.

Any ideas?
 
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