Have I blown up my motor?

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cyclepro101

cyclepro101

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May 13, 2009
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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
 
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Bikeguy Joe

Bikeguy Joe

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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

cyclepro101

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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?
 
X

xlite

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cyclepro101 said:
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?
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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.
 
cyclepro101

cyclepro101

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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
 

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Bikeguy Joe

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
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They are pretty much all the same with slight variations. They come from a few different factories around China.
 
Bikeguy Joe

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
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30:1 was not likely too lean, however, you could have had the fuel to air mixture too lean. Tuned pipes usually require a bigger jet/more fuel.
 
Pablo

Pablo

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Dec 28, 2007
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Have I blown up my motor?
Click to expand...
YES. Fail.


cyclepro101 said:
Maybe 1:30 was too lean. Might pull back to 1:25. Or it could of just been a bad jug?
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Bad plating.

NO STINKING WAY 30:1 is "too lean". Sorry but that's not an oil related FAILURE.

So you told the dealer you rev'ed the **** out of thing and rode it like a raped ape and he gave you a new engine, no charge? Not bad!!
 
2door

2door

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Reminds me of my old fuel dragster days. I've seen the innards look like that after one run.
Keep us posted on how your dealer is taking care of you. You might want to consider taking it a bit easier on your new engine. These are after all cheap, simple little motors that were never designed to take a lot of abuse. "Screaming" implies that you might have pushed the envelope a little. Good luck and keep us informed.
Tom
 
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