Yamaha V Star Forum

Full Version: Low Cylinder Compression
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I'm measuring only 90 and 95 psi of compression in both cylinders, on a V-Star 650 Classic bike that's supposed to be almost new (just bought it; on the outside it looks hardly used at all and I tend to believe the guy that sold it to me that it's the original miles).

The bike is from 2007, i.e. about 8 years old, has only 6600 miles on the speedometer (I'm in Canada - the riding season is short around here). I would expect externally exposed parts, like exhaust, breaks, etc to deteriorate with time, but the engine itself should be like new.

I've measured valve gaps - 0.004 and 0.006 - picture perfect. I also noticed that it was kinda hard to start it. You had to keep it on choke for several minutes. Any attempts to give it some throttle would stall it. When the bike gets hotter, its response would be generally much better.

Could carbon deposits get developed on the valves at only 6600 miles?

Regarding the remedy - I read somewhere on the internet that misting water into the air intake on a running engine could wash cab build up. Is it true?

Thanks in advance.

Ottawa, Canada