Comer 80 Stalling

Matt Miskoe · Joined: 27 Dec 2011 Posts: 12

So my son is running a Comer 80 on a cadet chassis, first season w/ this motor, his first season at sprint races. As a result we're learning, sometimes faster than other times.

Last weekend was an outstanding failure with him DNF'ing 4 out of 4 sessions due to the motor not wanting to stay running if he came off the throttle. Due to other carts stalling/spinning causing slow downs, he spun once and a very slow (15mph) turn on the course there were ample opportunities for the motor to get down low in the RPM range. The motor has always been prone to stalling if it is turning decent RPM, he comes off the throttle and it gets low in RPM it won't catch and stay running.

The motor seems to be sound, I did a leak down the night before and it was nearly zero. I've changed the diaphram and cleaned the areas/passages below it.

I've got the idle stop cranked in as far as it will go and although I have messed w/ the needle screw closer to the motor, I put it back to where it had been. I change the spark plugs a lot as this seems to help, but that might be in my head.

First question - which is which on the two screws on the carb? (Closest to the motor = high or low speed?)

2nd - which of these should I be adjusting to cope w/ a low RPM problem

3rd - I assme that loosening either of these two screws allows more fuel, so I suspect I want to loosen which ever is the low speed adjustment.

Any thoughts/help would be appreciated so we can at least try for changes in the right direction to start.

Walt Gifford · Posted: Thu Sep 20, 2012 9:58 am Post subject:

The needle closest to the engine is the low speed. Sounds like you're loading up with fuel by being off the throttle too much. just get him to burp the pedal anytime he has to slow down and maybe try a hotter plug if they're always fouling. Close both needles then open 1/2 turn on the high and 1 turn on the low. If you think the engine is starving for fuel or running hot you can try 3/4 on the high and 1-1/4 on the low. Should get you in the ballpark.

Gif Cool

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marc-andre hubert · Joined: 10 Apr 2012 Posts: 174

I am new to these also but i have been playing with them for few months, and daughter did same thing this weekend, in the formation lap she was going so slow motor got a bit too much fuel, did not help that it took 3 laps to get them going, plug was wet, screw needle in for leaner mixture, change plug and go, that is if your carb is operating right to start with

Gregory Dzielinski · Posted: Mon Sep 24, 2012 11:13 am Post subject:

What are your low & high needle settings?

Another words, how far out do you have the 2 needles turned ?
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