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Larry, another way to look for the problem cylinder would be to use compressed air. If your compression tester is a two piece design with a quick connect, try your air hose connector on it, if it fits, you are in business. If not, try to get an adapter from NAPA that would screw into the plug hole. They are available as I have two different sizes I have used to put air into cylinders for valve seal replacements. Dial your compressor regulator down a quite a bit, as high psi is not needed nor recommended. You will also need to make sure your piston is positioned in the down-stroke just before TDC. Hook your air up and seeif you get any hissing out of your airbox or exhaust. You'll need to listen closely. A burned valve will leak, whether the engine is hot or not. If you heara lot of hissing (some is normal) inside of the engine block, your rings on that piston would be suspect. With that pressure on the piston, try to manually turn the engine over with a wrench (yeah, you gotta get to the crank bolt). Do not use the starter to do this!If it turns very easily,and there is no hissing coming from the airbox or exhaust, then I would bet the rings are the problem.You should have a decent amount of resistance when trying to turnover the crank since it is coming up on the compression stroke.A compression test will give you the same results, but it will not tell you the rings or the valves. I have used this on all kinds of vehicles. Hope this helps! BTW, make sure you have the tool you are turning the crank with off of that crank bolt before pressurizing any cylinder! That thang wil fly off to holy :cooldevil:if you don't and damage the bike or possibly your noggin'!
Larry, another way to look for the problem cylinder would be to use compressed air. If your compression tester is a two piece design with a quick connect, try your air hose connector on it, if it fits, you are in business. If not, try to get an adapter from NAPA that would screw into the plug hole. They are available as I have two different sizes I have used to put air into cylinders for valve seal replacements. Dial your compressor regulator down a quite a bit, as high psi is not needed nor recommended. You will also need to make sure your piston is positioned in the down-stroke just before TDC. Hook your air up and seeif you get any hissing out of your airbox or exhaust. You'll need to listen closely. A burned valve will leak, whether the engine is hot or not. If you heara lot of hissing (some is normal) inside of the engine block, your rings on that piston would be suspect. With that pressure on the piston, try to manually turn the engine over with a wrench (yeah, you gotta get to the crank bolt). Do not use the starter to do this!If it turns very easily,and there is no hissing coming from the airbox or exhaust, then I would bet the rings are the problem.You should have a decent amount of resistance when trying to turnover the crank since it is coming up on the compression stroke.A compression test will give you the same results, but it will not tell you the rings or the valves. I have used this on all kinds of vehicles. Hope this helps! BTW, make sure you have the tool you are turning the crank with off of that crank bolt before pressurizing any cylinder! That thang wil fly off to holy :cooldevil:if you don't and damage the bike or possibly your noggin'!
