hesitation and gas in oil.

[nuclearmuscle523]

Hey there guys.
Got a tomos nitro with a 50cc gy6
Previous owner says he put a 100cc kit on it. Likely to be around 80cc from my research.
I bought a new stock carb and put a #88 main and #38 idler in it, and changed the spark plug.
He could not get the scoot running after he did the swap.
Oil and gas blows hard out of the dipstick tube when I have it taken out and motor is running. I assume I still need to seat the rings.
Motor bogs and hesitates when running around mid to heavy throttle.
Any help would be much appreciated. Thanks guys.

[Deleted]

make sure the vent from the valve cover is not pinched.
what does a compression test say?
an 88 is too lean for a 50mm bore it needs a 95 assuming a free flow air filter is being used.

[nuclearmuscle523]

When I completely remove the air filter it revs about 500 more on the top end, so a considerable difference. The valve cover has just the barb fitting, no line. I don't have a compression tool.

[nuclearmuscle523]

Just noticed the green wire to the cdi was cut. I reconnected but no change. I also put oil in it. There was like no oil in it.

[90GTVert]

Sounds like there's a problem with the piston rings to me.

That green wire may have been a restrictor. If it ran and shut down OK, that's prob what it was. Some have a loop of wire that when cut removes a rev limiter.


Oh, and :welcome: to the forum.

[jmkjr72]

yep gas in the oil i would suspect a ring issue
and wouldnt run it till you figure it out
gas in the oil will burn up your crank bearings