GY200 problems

[Brett]

I last posted in 2014 after buying both a used Yamoto and Lifan GY200. I've spent the last 3 years, when I've had time, building one good bike. Yesterday, I decided it was time to start the bike for the 1st time and it fired right up. Here's the issues I'm having:

1. The engine didn't seem to have a lot of power. I couldn't spin the back tire in the gravel.
2. The clutch seemed to slip under hard acceleration. I loosened the clutch cable and that didn't help. Using diesel oil in the crankcase, I think 15w40.
3. After I rode up and down the street, the bike died and would restart, but then died again, unless I kept the throttle open. I'm running a new Keihin carb with a new unifilter and fresh gas.
4. The original owner put an iridium spark plug in, could this be part of the issue?

Any thoughts would save me a lot of troubleshooting!

Thanks in advance.

[pete]

I think you need to look at the carb...
you say a new keihin... was it or did you jet it for your motor...
Sounds like it could be lean... revs ok but no power can be a sign of a
lean mixture...
or it's picked up some dirt & blocked a jet...


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