Have I blown up my motor?

cyclepro101 · #1 07-01-2009, 10:14 PM

Well I finally had it going great. I got the SBP Tuned pipe and it was screaming. But I went out to start it and noticed it was hard to start and would not idle. Also there is no or very little compression. With the cluch out I can push the bike around the garage. Also when I get it going its very clunky, it will go ok for a while then just go CLUNK and stop. The fuel is 30:1 and fine. The plug is fine, very light charcol. The carb is perfect. I thought it was electrical as is goes ok but then going down a hill off the gas it just dies intermitenly. I started it up this morning for my son to have a listen and once I got it going all he said was "that sounds bad". Then CLUNK, it stopped. Still no compression.
So what should I do. I have been ringing its neck flat out a bit lately should I just replace the ring? What else should I look for when I have the head and barrel off? I was told to check under the clutch cover as I may have blown and oil seal? Are these hard to change?

Steve

**Bikeguy Joe** · #2 07-01-2009, 11:02 PM

Sounds like you may have smoked it...look for scratches on the cylinder wall. You may get by with a new set of rings.

cyclepro101 · #3 07-02-2009, 12:40 AM

There is just no compression. Its hard to tell if an oil seal is gone. How much should or would be leaking out behind the clutch if it was gone?

xlite · #4 07-02-2009, 07:43 AM

Quote:

Originally Posted by cyclepro101

There is just no compression. Its hard to tell if an oil seal is gone. How much should or would be leaking out behind the clutch if it was gone?

The seals, although important for operation, have little to do with compression. I would look at the piston, rings, and cylinder walls. Only takes a few minutes and tells a lot. Might be bearing gone and took the top end with it. Not costly to repair but sometimes better to just pick up a whole new engine for $75 and use old for parts.

Pablo · #5 07-02-2009, 08:24 AM

Quickly pop the head off. Too easy.

freewheeling frank · #6 07-02-2009, 12:01 PM

sounds like broken rings or bad wrist pin bearings gotta pullthe head and jug

cyclepro101 · #7 07-02-2009, 08:00 PM

OK But what am I looking for when I get the head and jug off?

Pablo · #8 07-02-2009, 09:12 PM

Suspicious holes in the piston, alleged gouges in the bore, loose parts laying about....the usual suspects.

fm2200 · #9 07-02-2009, 09:40 PM

These engines are not good at screaming

cyclepro101 · #10 07-03-2009, 12:00 AM

OK, Thanks team. Check this out. I also e-mailed back to my Aussie supplier and he said he will E-mail the photos to China and he will send me a new motor.
It looks like all the chrome came off the inside of the jug? Also there is bits of this metal? stuff in the bottom end too.

Steve