Carby Need help getting carb tuned

[German_guy]

Hello guys. Recently I build my Minarelli Hybrid 70cc with a windowed piston. I’m not using a reed valve or anything fancy, just a basic setup with a china pwk21 carb. I’m guessing that I can’t get the carb tuned right, that’s why I can’t get my bike to run. What jets are yall using?

 

[Xlr8rr]

78 main needle clip top slot

 

[Itsssmeee]

Hello guys. Recently I build my Minarelli Hybrid 70cc with a windowed piston. I’m not using a reed valve or anything fancy, just a basic setup with a china pwk21 carb. I’m guessing that I can’t get the carb tuned right, that’s why I can’t get my bike to run. What jets are yall using?

Windowed piston you need a reed

 

[German_guy]

Windowed piston you need a reed

Okay that makes sense now that I think about it. Guess I have to get a different piston then. Thanks for the help

 

[Gordy]

This explains everything you need to know

Reed valves (informative)

I decided to share my personal opinion on reed valves. The short and skinny: Do not reed valve an engine without a pipe upgrade!!! You will have to add a windowed piston or window your own piston. Reed valves add power, however it will not on otherwise stock engines. And a little more in...

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