I have a 00 polaris virage tx and have the engine out to replace the magneto. I would like to do a leak down test on the lower end while it is out. What is the best way to do that? The carbs and exhaust are off. I reason for the pull is because I could not get the ski to do more than 35 mph. I have replaced all the electronics on it and still could not get it to do anything. any help at this point would be greatful.