97 EZ GO with Robin EH29C, spark

[L&D Small Engine]

I just rebuilt a Robin Eh29C engine out of a 97 EZ GO cart. Jacked up back wheels after dropping engine back in and fired it up. Runs great until high RPM's, then I loose a small amount of spark (sputters a little). Let off throttle, press throttle again and runs great again until high RPM's. Is this the high side of the coil that bad? Or does EZ GO have a rev limiter and this is normal?
Thanks in advance to anyone that can help

[Larry1950]

Rev limiter kicks in about 4500 rpm. Plus make sure the valves a adjusted properly

[L&D Small Engine]

Rev limiter kicks in about 4500 rpm. Plus make sure the valves a adjusted properly

So EZ gos do have rev limiter? Valves are properly adjusted to .004"

[Larry1950]

The Robin ignition system has a built in rev limiter. The Robin 29 or 35 is a very detuned motor. A 295cc or 350cc motor is capable of 30+ hp, however the way Robin is built it would grenade at the rpm's necessary to make 30 hp (9000 and better) The valve train,crank, etc. simpley will not take those rpm's. The carburetor is very small, jetting is lean, ports are small, valves are small and the valve springs are weak, and very mild cam timing.. I suspect that valve float will occur at about 5000 rpm or so with the valve/spring combination. So the rev limiter is set to prevent the valves from hitting the pistons. When valves meet pistons bad things happen inside the motor.

[L&D Small Engine]

Thanks for your post! I was pulling my hair out for nothing. And yes, bad things do happen when valves and pistons meet! FYI, greetings to Battle Creek MI Larry. I havent been to the cereal city in years. Thanks again!

[Larry1950]

Only been in North Dakota a couple of times, but been to South Dakota many times pheasant hunting.

[L&D Small Engine]

Very nice!

[L&D Small Engine]

So there is another problem now. Engine ran great for 30 seconds and idle rpms started to float, a backfire, now no spark or anything. Im ready to scrap this Robin engine. Any ideas anyone? FYI, I ohmed the pulser coil and got 20.8 OHMs. I dont know if this is in spec or not. Thanks in advance to anyone who can help.

[Diajoh]

I have a 2001 exhibitors with eh29C engine. It surges at low speed. What could cause this