Piston rings the problem?


XS400 Enthusiast
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how can i see if my rings are bad? do i need to check the gap? really want to figure out if theyre bad before trying to track down a set...
Is the top end off? Take the rings off the pistons carefully; do not mix them up. The rings are directional and they also need to go back on the same piston, but I digress. Take the rings off and stick them in their respective barrel, one at a time, about an inch or so from the top. The rings need to be square, so use a piston to push them in or carefully measure all the way around the circumference. Use a feeler gauge and you're done.
top end is not off, i was hoping my problem wasnt internal, but my compression tests were low, and the one problem cylinder was low low, and i have some blow by so this leads me to think thats its piston rings. i want to measure first though.