Getting a Project Going- Compression

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efinke96
New to XJR
New to XJR
Posts: 5
Joined: Mon May 29, 2017 9:38 am

Hey everyone, new to the forum. This is my first time working on a bike like this, usually a car guy, so forgive any ignorance. Bought a non runner from someone who said a new fuel pump was needed for 900 bucks, seemed like a good deal. As far as I can tell everything he told me is true, but still running into some problems. My main concern is some slightly low compression.

First off, changed the oil and filter. Bike had been drained before storage by the previous owner.

Secondly, when i was pulling the spark plug on cylinder one and went to put in a new one, it revealed a cross threaded spark plug hole. Just a little at the top, but enough to stop progress until a back tap comes in. Absolute bummer, but it really is very minor so I'm not too worried about it. The other three are fine though, and all cylinders appear to have spark. All spark plugs were replaced.

On the other three cylinders, Compression was around 130-135 for all cylinders. I'm assuming the cylinder I wasn't able to test will be around the same, but obviously will have to wait and see. For the sake of this post let's assume it reads between 130 and 135 like the others. I know this is a little low, and based on what the PO told me, I believe it will be a head gasket and valve adjustment. I'm fully willing and able to do both jobs, but I'd love for the bike to run at least on starter fluid before I start tearing it down. Does that sound possible with these compression numbers? I just want to hear signs of life before diving into the engine.

I'll keep updating with progress on the bike. I appreciate any and all advice. Thank you in advance!

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