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My 2000 K1200LT has about 75K miles on it. Up until the past couple oil changes I never had to add oil between changes at 6K miles.

Recently I've had to add a little occasionally to bring it back up to where I could see it in the sight glass.

I figured I had a broken piston land or something. I just finished doing a compression and leak down test.

Bike was warmed up before testing.
Compression was no lower than 170psi and no higher than 175psi on all cylinders with the throttle held wide open. Air filter was left in place.

Leak down test was about 20% on all cylinders which I thought was pretty good.

The results surprised me, I thought I was going to find a problem.
Questions: Do these results seem good? I thought they were okay....
Should I switch to a K&N air filter now? (Okay never mind, that's a joke. ;) )

I have no visible oil leaks and no explanation as to why I seem to be using oil.
Maybe my bell housing is slowly filling up? Yikes! (Clutch is okay so far.)
Saddleman, David S., or any other enlighted opinions most welcome. Thanks in advance.
 

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Curtis while not in that group I have done a few compression and leak down tests.

As far as numbers not sure of the Compression # on the LT but the nice numbers and low variance you have sounds great. The leak down again is great.

EDIT: How many cranks did you go for each cylinder? And did your gauge hold the high from all cranks?


I have done cold compression tests and wonder if that would yield you different results?

I have also done wet compression tests where your add oil to the cylinder through the spark plug hole. This may help you if you receive odd readings using this method.

And just to ask where can oil go in a LT? You can use it but but your compression/leak down numbers would not support that.

You can loose it through the rear main seal?

Can it mix into the antifreeze?

Valve adjustment, valve seal, seat? An overheated exhaust valve could probably use a lot of oil especial blowing by a bad valve seal.

What case could/would need to be cracked underneath fo a leak?

Could you be suffering the breather/throttel body hose leak that is going around?

I am just curious what your suspicion may be as I am sure you have looked for oil leaks visually.
 

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Your compression and leak down tests are great. No evidence of a problem there.

If you have not visible oil leaks, I would think there are a couple possibilities. Valve seals would be one, but would cause a little smoking, other than the normal cold start smoke we sometimes see.

Another is the crankcase breather hose assembly. These often get old and crack, causing oil to be leaked out, on top of the engine. Quite a bit of oil can build up there before it gets deep enough to overflow and become visible as it drips down.

To check for the breather hose leak, pull the side fairings and look down around the base of the throttle bodies, and in the depression at the left rear where the breather hose attaches to the crankcase fitting.
 

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Your compressure numbers look good. All four of my cylinders are close at 10 revolutions but at 15 revolutions # 3 cylinder on mine stays the same & the other cylinders go up a little more. My leak down @ TDC ( indicated with a dial indicator ) are #s 1,2 & 4 2 to 4 % # 3 is 30%. The fact that all of yours reads the same would seem to me that your in good shape. Mind you all compressor & leak down testers read a little different. All it takes is a different length or diameter of hose to get a little different reading.

Have you changed your brand of oil lately. The reason I ask is I get free oil from Mobil & the delvac I use has always used more oil than any other brand that I have used. All the other employes at work have noticed the same thing.
 
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