49cc terminator cycle problems

I have a pocketrocket terminator 49cc. ive had it since they first started coming around. it was wrecked and now it doesnt run right. it seems like the engine is holding back speed. it wont go past 40 k/h. the top is 60. i ve tried every small thing i could. i thought about rebuilding the carberator but wasnt sure if it could be the problem. and the carb doesnt have a cover or filter i lost it. and sometimes it will go fine then other times ill be going and the carb will make back firing sounds. please help me

 

Hello barnhouse,

As you've probably found out by now, most small engine shops refuse to work on these cycles. I have worked on several (The only ones I'll work on are the ones that come in to a local pawn shop that sends me ALL their business, which amounts to quite a bit). There is literally no telling what the problem is, but I can tell you where I'd look first. Look at where the throttle cable connects to the carb. Open the throttle wide open with the control on the handlebar, then reach down and see if you can open the throttle more on top of the carb. If so, you have a problem with the throttle control and/or adjustments on the handlebar.

As for the backfiring/popping, I suggest a new spark plug before anything else. The spark plugs that these come with are as prone to failure as the rest of the components on the bike.

 

It sounds like it's falling on its face and it could possibly be as a result of not having an air filter installed...If you've run it alot without such, that is. If so, I'd recommend having a look at the piston and cylinder through the exhaust port by removing the exhaust manifold. The engine may have sucked in particulate matter and toasted the piston and cylinder and more inside the engine. You should not run any engine without an air filter, especially a two-stroke!

 

Puey, why is it especially important for a 2 cycle not to run with the air cleaner off?

 

thx for your help guys. i will have a look at the piston and stuff though

 

The air/fuel/dirt ingested by a 2 stroke doesn't just enter the cylinder and get blown out the exhaust like it does on a 4-stroke. It goes through the crankcase...having the opportunity to ruin the rod bearings, crank bearings, etc...
Also, most 2-strokes have very small cylinders, pistons, and usually only one ring. Most 4 strokes have several times the size of the components and 3 rings. A smal amount of dirt ingested by a 4 stroke may leave only minor scratching, maybe even a gouge in the cylinder, but it can continue to run. That same small amount of dirt can render a 2 stroke useless, because there is much less surface area on the parts to accept the damage. A pinch of dirt fed to both may go unnoticed by the 4-stroke, but permanently shut down the 2 stroke.