Compression Problems
Hi everyone, I'm looking for a little help here. I recently rebuilt the top end of a bike for a buddy of mine because it was burning oil. The bike is an 83 Honda Shadow 750. I've had it apart several times with different issues now so here's the work I've done on it. New valve stem seals all around, new standard size piston rings, standard bore honed by a professional machinist, seated the valves. The lifters on this bike are hydraulic and are supposed to automatically adjust but there are shims underneath the tappets that I'm not %100 sure went back in where they came out, but I think they're right. So here's my problem, I tried to start it yesterday and it wasn't having any of that, it would pop occasionally but wouldn't fire, so I broke out the compression tester and I have 150 psi in the rear cylinder, and maybe 20 psi in the front, both cold measurements. I'm going to do a leak down within the next few days but I was looking for some input on what you think it may be? I should also note that I had the bike running after the hone and new rings, but it was running really bad, that's when I pulled the heads off again, ground and seated the valves and moved one tappet shim, but I don't remember which cylinder that was on.
Any input is appreciated. Thanks!
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