94 150 yami carbed 2stroke - cough/skip

[esteym]

Just finished timing and sync-ing the carbs etc. as well as rebuilding the carbs. (blew everything out and soaked)

My engine is coughing / missing now (not sneezing). what should I adjust to fix this? IT is also idling a bit high. I backed the carb screws back to 3/4 turn from bottom. Idle dropped from 1100 to around 850. Manual says it should be 675 or so. It was skiping before that though. The idle speed screw is set at 1 1/8.

thanks

 

[Ryan M]

Re: 94 150 yami carbed 2stroke - cough/skip

Sounds like you are running lean. Try starting fluid in carbs while running to see if it evens out or rpm picks up... Maybe wrong float bowl hieght?

 

[esteym]

Re: 94 150 yami carbed 2stroke - cough/skip

I'll try the starting fluid trick. I'm pretty sure I got the float bowl height correct, but if it gets fixed by the starting fluid have done it incorrectly? Would this cause the lean skip? Thanks

 

[esteym]

Re: 94 150 yami carbed 2stroke - cough/skip

Just a quick update:

I adjusted the throttle cam, back to spec. I accidentally changed it when I was sync-ing the carbs. (this was causing the high rpm before)

Now it runs great except it only hits 4500 rpms - before it hit 5100-5200. It is like it is not running on all cyl.

Would advancing the timing (assuming I got that wrong - I just set it to spec not with the light) fix this? Also I still get a skip every once in a while mostly when the engine is decelerating down from full throttle.

any help would be greatly appreciated - im leaving Saturday for a trip on Lake george and would like to have it tip top before then.

Thanks

 

[esteym]

Re: 94 150 yami carbed 2stroke - cough/skip

Just a quick update:

I adjusted the throttle cam, back to spec. I accidentally changed it when I was sync-ing the carbs. (this was causing the high rpm before)

Now it runs great except it only hits 4500 rpms - before it hit 5100-5200. It is like it is not running on all cyl.

Would advancing the timing (assuming I got that wrong - I just set it to spec not with the light) fix this? Also I still get a skip every once in a while mostly when the engine is decelerating down from full throttle.

any help would be greatly appreciated - im leaving Saturday for a trip on Lake george and would like to have it tip top before then.

Thanks