Norm, maybe you can figure this out-
I can start my brand new engine but it barley runs and doesn’t respond to the twist of the throttle. I ordered this engine because after replacing the plug, plug wire, CDI, magneto, etc. on my other engine and finally threw in the towel on it. It’s a 66cc Grubee ( motor only) that has a few upgrades like a sick bike parts shift kit and expansion chamber exhaust. I couldn’t get it to fire with my old CNS carb so I switched back to the factory carb.
After many frustrating attempts with both carbs I found a working CDI and was able to get it to turn over. I removed the chain that drives the rear wheel and can get it to run by pedaling. The problem is that is it is running at a weak idle. Goosing the throttle makes it louder but does not increase the rpm’s. The slide does move up and down inside the carburetor. I have tried all for settings by moving the E clip on the needle to no effect. (Although with the lowest setting it stalls.) I bought a brand new factory carb and played with the needle setting with exactly the same result. Tried filter and no filter- so I don’t think it’s the carb. I don’t think it can be the plug because it runs the same with the new 3 pronged plug or an old one gaped at .025. The CDI gives enough juice to the spark plug to start it and the wire is a SBP upgrade so I don’t think the problem is there. I replaced the intake gasket with a new one and smeared bearing grease around the joint where the carb mates to the intake as a quick check for leaks. No change. Removed the muffler and blew thru it, no dead mouse. Fuel is brand new and mixed about 25 to 1 and seems to flow freely. I have checked to make sure the the head bolts are tight.
I can get it to idle at , oh I’m guessing. 800 rpm but that is it. No power and twisting the throttle must be doing something because the slide moves and the motor gets louder but does not go any faster.
I give. Any suggestions?
I can start my brand new engine but it barley runs and doesn’t respond to the twist of the throttle. I ordered this engine because after replacing the plug, plug wire, CDI, magneto, etc. on my other engine and finally threw in the towel on it. It’s a 66cc Grubee ( motor only) that has a few upgrades like a sick bike parts shift kit and expansion chamber exhaust. I couldn’t get it to fire with my old CNS carb so I switched back to the factory carb.
After many frustrating attempts with both carbs I found a working CDI and was able to get it to turn over. I removed the chain that drives the rear wheel and can get it to run by pedaling. The problem is that is it is running at a weak idle. Goosing the throttle makes it louder but does not increase the rpm’s. The slide does move up and down inside the carburetor. I have tried all for settings by moving the E clip on the needle to no effect. (Although with the lowest setting it stalls.) I bought a brand new factory carb and played with the needle setting with exactly the same result. Tried filter and no filter- so I don’t think it’s the carb. I don’t think it can be the plug because it runs the same with the new 3 pronged plug or an old one gaped at .025. The CDI gives enough juice to the spark plug to start it and the wire is a SBP upgrade so I don’t think the problem is there. I replaced the intake gasket with a new one and smeared bearing grease around the joint where the carb mates to the intake as a quick check for leaks. No change. Removed the muffler and blew thru it, no dead mouse. Fuel is brand new and mixed about 25 to 1 and seems to flow freely. I have checked to make sure the the head bolts are tight.
I can get it to idle at , oh I’m guessing. 800 rpm but that is it. No power and twisting the throttle must be doing something because the slide moves and the motor gets louder but does not go any faster.
I give. Any suggestions?
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