Carb issues??

Jay Cobb

New Member
Mar 28, 2018
New to all this. We just finished my son's 80cc motor installation about 2 weeks ago. His friend has same bike and motor (i think). My son's is bogging when throttle is pressed hard and his friends is much faster and responsive to throttle. I noticed my son's use much more gas than his friends. Was thinking his is running rich but my son's exhauat gets much hotter than his buddies. He is running it a little richer for break in. But just seems such a big difference in the 2 bikes when it comes to speed and acceleration. Can anyone give me some advice to tweak or adjust on it?? Thanks guys!!!


Well-Known Member
Sep 30, 2012
I never do any real tuning until it has run in for quite a while - if it 2-strokes only when going uphill, I'd drop the needle a bit, but that's all.


Mar 1, 2018
The engine requires a pretty long break in. Something like 150 miles or more. As your son keeps riding it should get better. The bogging at wide open throttle usually means it's running rich but the hotter exhaust sounds like it's running lean. A good way to tell is to look at the spark plug. If it's black and oiley then your too rich. If it's a light grey or white and clean your too lean. You want something in the middle like a dark brown or chocolate color. There's a little clip on the carb needle that looks like Pac-Man and 5 slots to adjust it up or down. Raising the clip will lean out the mixture and lowering the clip will enrichen it. Also the 16:1 ratio mix is waaaaay to much, even for break in try running a 24:1 and then 32:1 after a few tanks of fuel