Compression

Rickrod · Posted: February 28, 2009, 4:29 pm Post subject: Compression

I'm getting a little oil leakage down back of the engine.
I read an article by Farrell Hope which he describes an oil leak from the breather caused by over filling the bike with oil.
I measured the exact amount and it still leaks but not so bad.
I pulled the air boxes there was some oil residue.
Read some threads here saying it could be the rings.
So I did a compression test.
right cylinder 122
Left cylinder 120
B.T.W. I had the carburettors off the bike when I did the compression test.
I have uploaded a picture of the the plugs.
The last few mounths have only ridden short 10 to 20 mile rides infrequently.
Too damm cold!
Let me know what it means to you.

Thanks in advance
Rick

xsjohn · Posted: February 28, 2009, 4:42 pm Post subject: Re: Compression

Compresson on a well sealed stock engine should read 150 PSI...Irun mine lower but that was intentional...xsjohn

Rickrod · Posted: February 28, 2009, 4:48 pm Post subject: Re: Compression

I will try the test with a spoon of oil to test the rings.
Rick

Rickrod · Posted: February 28, 2009, 5:35 pm Post subject: Re: Compression

redid test
Right Cylinder 135 squrted in some oil got 150
Left cylinder 128 squrted in som oil got 140

It would appear my rings are showing wear.
How terrible is the 135 and 128 could the ring job wait awhile.

Rick

xsleo · Posted: February 28, 2009, 7:42 pm Post subject: Re: Compression

As far as the oil leak, it could be the gasket for the cam chain adjuster housing, where it fits to the engine. It could also be the o-rings and seal for the adjuster itself.
I wouldn't do a ring job at this point, the compression isn't that low or to much difference between the cylinders. I would ride it and see how much oil it is using.
Mine got to about 150 miles on a quart. Some burning and some leaking.
When I tore it down the pistons and rings were very worn. It needed a rebore, went first over.

Rickrod · Posted: February 28, 2009, 7:58 pm Post subject: Re: Compression

Thanks XSLEO
I think I'll wait and see how it goes.
The bike ran okay I wouldn't race anyone for pink slips.
oil really seems to be the blow by I will check those places you mentioned.

Rick

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