I recently decided to buy a compression tester to check my 2002 Sportster LT. About 7 or 8 years ago I had a friend test it and each cyl in both engines read between 140 and 150, all was good. With the tester I just bought from O'Reilly it is reading a consistent 80-85! Now I've noticed a little loss in power over the years but if those readings are correct, I would think I'd be seeing a tremendous loss in power. In this time period I've had maybe 2-3 overheating spells wear the water intake got clogged which may have caused the cylinder sleeves to warp? Also this past winter, my dealer did something wrong on the winterizing since I had a freeze plug blow out in each engine. They repaired the one that blew in the spring and I had the other welded at work since I ran it all summer fine. I'd like to hear opinions if this this tester is working properly or I'm doing something wrong in using it. If I am really only getting this low of compression what will be needed to repair. Perhaps the head gaskets could be bad? I'm planning on borrowing another tester from O'Reilly or auto zone for comparison. I suspect the boat has around 400 hours on it but I'm not really sure. I've always used xps full synthetic. Last year I did pour a quart of evinrude full synthetic in since I was out and the light red light came on and didn't have my spare quart of xps with me so I bought what I could. <br><br>If I do need these engines overhauled, what kind of ballpark price tag would that carry?