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When to say When

1064 Views 6 Replies 5 Participants Last post by  awd86

I've been working on my project '79 cx500 for a few months now and I only have a couple free weeks left. Bought it for $200 off a farmer who said it'd been sitting in his barn for 2 years, but it hadn't been registered since '98. I made sure it wasn't seized before I bought it (learned that lesson the hard way on a seadoo).

Before I started spending money on the bike it had to run, I wasn't overhauling the engine. After a basic carb cleaning and fluid change, it ran on one cylinder at about 1100 rpm. The clutch was free so I rode it up the driveway into the garage, where it remains. I've replaced the brake MS, pc'd the tank, replaced the front tire, added the ignitech ignition (b/c I thought the module was preventing one cylinder), and most importantly - completely overhauled the carburetors.

After the carbs were finally done (switched for a, '81 pair), for the 8th time, it would run for 5-10 minutes at a time with the choke on. Yeah, I know it was lean...but no amount of fiddling with the pilot/float/jets/needles/air filter/air leaks/etc would fix it. In fact, I had the pilot at the richest setting that wouldn't kill the bike immediately. This 5-10 run time was the best it'd been, but it would always die b/c the spark plugs would fowl with oil and gas. There was also a considerable amount of white-blue smoke from the left cylinder (nearly none from the right-the heat of the exhaust confirmed that both cylinders were firing). When I drained the oil, it was a little cloudy, thin, but not milky. The coolant still looked new.I pulled the heads (sts) and found only minor slop in the valves. I got new seals, but I'm going to measure the guides and probably not replace them.

Theres the setup, long story

So heres the issue: The RH cylinder (the one that WASN'T smoking) is very pitted. I don't know how to post pictures or I'd show everyone. I can only find one OS +0.25 piston and set of rings online, but I'm afraid it might take more than that.

Can I just go OS on one piston? Can I resleave this cylinder? Should I scrap the engine/bike? I'm already up to $800 on my $500 budget and the person I'm building for decided she'd rather have a vespa (hssss).

Any ideas?
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Called the machine shop. He suggests not going OS on a single cylinder, but he doesn't think he could resleave the cylinder either. Anyone have success with this before?
Glad to hear everyone one my side! So, I definitely took the path of most resistance and bought a middle section on ebay (probably from a forum member...picture looks familiar). I'll just throw a bag over the whole thing before it goes into storage for the next 7 months

Beside refilling the oil, any recommendations on sealing up the block while it gets stored? The head gaskets are no good, but I might bolt a piece of plastic in to seal her up.
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