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Discussion Starter #1
I have a 1994 Vulcan 1500 that the front cylinder compression is 120 or so,according to the manual it's suppose to be between 50 and 85 psi. Am I looking at a problem or just leave it? It started with just one plug in and the back plug holes open with just the leftover gas in the bowl.
 

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Compression release problem?

The front cylinder has the compression release built into it so the engine can turn over faster and start easier. It sounds like the system is not working on your bike I have never had the system apart on my bike, but I have seen how it works on a dirt bike with a manual compression release. The idea is it holds the intake valve(s) open at cranking speed to lower the load on the starter. Thats why the compression spec is lower for the front cylinder. Does the bike turn over slowly at all when starting? The service manual and/or someone who has more experience with the valve train could answer you further..... The good news is higher compression is better than too low compression:D. The bad news is I believe the engine has to be dropped down to remove the valve cover and even look at the mechanism.
 

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I think your right about pulling the engine,if I do that I might do the top end depending on what it looks like.I'm going to do another compression test,this time I'm going to hold the throttle open (realized I didn't do that last time) it rolls over and it did start.SO not sure yet
 

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According to the factory manual. the compression release may not work if the engine is well broken in and turns at a higher speed on the starter. I wouldn't worry about it.
 

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First, you should never do a compression test with the engine in a condition that it could start. Unplug all plug wires, disconnect ECM, unplug ignition coils, there are several ways to accomplish this. Throttle plate should be wide open to allow a full flow of air into the cylinders.

The reason you are seeing an abnormally high compression is because the Kawasaki automatic compression release (KAC), works by centrifugal weights which are spring loaded. At approximately 6 ~ 700 rpms these weight springs are over ridden and the weights expand allowing the valve to close completely. When your engine started you exceeded the rpm range that would keep the valve open, thereby causing a complete cylinder compression.
 
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