Photos from Freddie Novellino's post
Depends on how long she had not run . Coal May have blocked the scraper and compression rings. Spray wd40 thru the carbs into the cilinders while cranking Let it rest for a while check compression again
According to my Haynes manual. The compression numbers are as follows. Maximum 171 psi....Standard 142 psi....Minimum 128 psi. My compression numbers were in the lower 120 psi range and I had a lot of oil consumption. There is no easy fix..... At minimum honing the cylinders and new rings are required. Freddie Novellino if you are a good mechanic, private message me, I may have a solution for you.
172 cold is what they are built at from Yamaha. I'd run it with petroleum oil and watch the #s go up.
Want to buy it lol
Maybe the valves ?
Get it started it might just need the carbon blown out. Don't rush to any conclusions till you check it out. There are plenty on here that can & will help but you will need to have a bit mechanically ability.
Mine were all under a 100 when I got mine running. Now they are max 130, Min 105. Still runs well but is in need of a valve grind and rings. Oil in the cylinders before a test doesn't alter readings so looking at valves / seats as the main issue. Job for winter.
I think your right. I do have the ability for sure just not the experience
I built this bike two years ago did everything my self but started off with solid engine. I'm going to need help with that for sure.
put some oil in the cylinders and they shot past 180.... cranked motor several times and tested several times now they are from 110 to 130 lbs