4 cycling at lower RPM's

[Junster]

My motor's not broken in all the way yet. Running at lower to mid rpm the motor 4 cycles alot. If I twist the throttle as it picks up it quits and starts to 2 cycle well but when I back off it goes back to 4 cycling. Is it too rich or to lean? Or is it just the heavier oil mix and just not broke in all the way? The plug read is very dark brown/black and dry. I have just a little oil at the exhaust. I'm running 16:1 just finishing the first gallon. Plan to goto 7oz. oil in the next gallon. It starts very easy and seems to have good power. I live at sea level.

 

[Junster]

As the engine has been breaking in this has almost stopped. 4 cycling on a 2 stroke is when the engine is firing on every other upstroke of the piston. Motor kinda sounds like it is going putt putt instead of wing ding ding ding. Only way i can think of to describe it.

 

[loquin]

Is this one of the happy time engines?

If it's a mitsubishi, (or other two cycle with a spark arrestor screen in the muffler) the spark arrestor screen can get fouled up and cause this.

 

[Junster]

No it's a 2 cycle HT but it has stopped now. I rode alot today and the motor is getting broken in. I think that's all it was.

 

[BSA]

I have found that you cant set the right mixture to idle (ans dun at low speed) well, and run well at high rpm without reprofiling the metering needle.

BSA

 

[Junster]

Ya I don't think the stock carb is going to let me get it perfect. But I'm about halfway thru my second gallon of gas and it's running pretty smooth now. Starting really easy. Thanks for the tips.