Engine Trouble Bike not starting after removing top end. Metal shavings possibly messed it up

[OrionSphere]

I removed my top end recently to rethread the threads in the casing for the head bolts. When i removed the top end I noticed that my bottom O ring was broken, and removed it. I've heard somewhere it will run fine temporarily with one O ring on the top. I got some metal shavings down in the engine, but hoped it would be OK. Sealed it all back up pretty well and got it started.

It's difficult to describe the running. Engine had difficulty starting and it felt very weak. I was able to get it up to 15mph but no more. Anytime I slowed down without throttle it immediately died.

After riding it more gently a few times it got worse. Squeaky sound when peddling with clutch in but I suspect that's from misaligned motor (I loosened motor mounts to make room for my drill when redrilling hole).

Overall very weak power, instantly dying. Hard starting. Feels weirdly smooth. Now it has quit starting.

Did O ring fall down in the engine or did the metal shavings fk it up? I doubt bad compression would make it run this badly.


This is a 48cc engine that bikeberry from 3 years ago that I've had running off and on in the past. Alot of the time it has been running lean and leaking oil all over the motor, but i fixed the compression issue a few weeks ago via the oil ring seal. At this point I wouldn't mind spending $150 on a Seeutek 66cc motor kit because the problems with this thing have been endless.

 

[OrionSphere]

O ring set arrives on Friday, but I doubt that will solve my problem

 

[DieselTech]

I removed my top end recently to rethread the threads in the casing for the head bolts. When i removed the top end I noticed that my bottom O ring was broken, and removed it. I've heard somewhere it will run fine temporarily with one O ring on the top. I got some metal shavings down in the engine, but hoped it would be OK. Sealed it all back up pretty well and got it started.

It's difficult to describe the running. Engine had difficulty starting and it felt very weak. I was able to get it up to 15mph but no more. Anytime I slowed down without throttle it immediately died.

After riding it more gently a few times it got worse. Squeaky sound when peddling with clutch in but I suspect that's from misaligned motor (I loosened motor mounts to make room for my drill when redrilling hole).

Overall very weak power, instantly dying. Hard starting. Feels weirdly smooth. Now it has quit starting.

Did O ring fall down in the engine or did the metal shavings fk it up? I doubt bad compression would make it run this badly.


This is a 48cc engine that bikeberry from 3 years ago that I've had running off and on in the past. Alot of the time it has been running lean and leaking oil all over the motor, but i fixed the compression issue a few weeks ago via the oil ring seal. At this point I wouldn't mind spending $150 on a Seeutek 66cc motor kit because the problems with this thing have been endless.

Pull the cylinder back off. Its wasted. Or at least I bet it is. You probably going to need a cylinder kit with piston & wrist pin bearing & gaskets.
Lack of power is due to only having 1 piston ring or you could have ruined the cylinder.

 

[DieselTech]

Pull the cylinder back off & get us some good pictures of the piston & the cylinder walls of the cylinder. Then we can make a better assessment.

 

[OrionSphere]

These are pictures I have already taken, I can take more tomorrow, I'm done for the night

 

[DieselTech]

These are pictures I have already taken, I can take more tomorrow, I'm done for the night

I bet it looks a lot worse now. When you get off 2mrow. At least parts are cheap.

 

[OrionSphere]

I bet it looks a lot worse now. When you get off 2mrow. At least parts are cheap.

I actually have this old top end that I had before bikeberry replaced my motor because I broke off a bolt inside the engine.. but it's smaller. This is confusing. Usable?

 

[DieselTech]

I actually have this old top end that I had before bikeberry replaced my motor because I broke off a bolt inside the engine.. but it's smaller. This is confusing. Usable?

Maybe they sent you a 66cc replacement engine. Is that cylinder set from your original 48cc engine.

When you get your engine apart 2mrow. You need to measure your piston diameter with a set of digital calipers.
That way we All Know what we are working with.

Plus you are going to need the measurements to order replacement parts.

 

[OrionSphere]

I actually have this old top end that I had before bikeberry replaced my motor because I broke off a bolt inside the engine.. but it's smaller. This is confusing. Usable?

There's an obvious difference in size. Come to think of it, bikeberry may have replaced my 48cc with a 66cc and never told me. It would explain why the M6x1 rethreading kit I bought didn't fit, and then I had to go buy a M8x1.25 kit that did work. Why would a 48cc have M8 studs?

 

[OrionSphere]

Maybe they sent you a 66cc replacement engine. Is that cylinder set from your original 48cc engine.

When you get your engine apart 2mrow. You need to measure your piston diameter with a set of digital calipers.
That way we All Know what we are working with.

Plus you are going to need the measurements to order replacement parts.

I'd rather order a new engine kit.