Hey all, this is my first post here on the forum, as well as my first bike ever (college project).
Some background: I bought the bike about a year and a half ago, picked it up real cheap because the the PO didn't want to deal with cleaning the carbs on an otherwise 90% mint bike hiding under some grease and grime. I towed it home (no license at the time) and started work on it. I pulled the rack of carbs off and tore them apart, cleaned them thoroughly and reinstalled them.
At this point it ran fine, apart from needing to replace the Reg/Rec, and it was a great starter bike. At the start of this season I decided to address a nagging problem on the bike; it wept oil from somewhere in the head gasket area. Not much, but enough to be annoying, topping up the oil every couple of weeks, really not a lot but the bike would sometimes smoke at stoplights, and it plain didn't look good with a film of oil.
I took the valve covers off, loosened the valve tappets, and removed the entire head cover assembly. If you have followed to this point, you may know what my problem was: the six little rubber pucks that seal off the head bolts from the oil flow. I had six new ones, put gasket material on each one and stuck em in there.
I reassembled the bike, lashed the valves and fired it up. At this point I had good news and bad news.
Good: Not only was the oil not leaking any more, but lashing the valves WOKE the bike UP! The throttle response was lightyears better.
Bad: An unholy clattering had developed from the engine.
My wrenching buddy and I let it run for a minute to see if it went away, then shut it down when it didnt. We decided that the cam chain must be loose, and a quick google search showed us that retightening the cam chain should be done before lashing valves.
The next day we decided to tear back into the bike and redo the lashing job, brimming with knowledge. I loosened the little nut, gave it a tap and had my buddy spin the engine while I snugged the nut up. We re-relashed the valves and started it up again. The noise was still there, so we went inside and banged our heads against the wall for a while.
(rinse and repeat a few times, no success)
After more attempts than i would like to admit, I decided we needed to re-remove the head cover and really see what was going on in the chain tunnel. I couldn't see much but I could feel the chain was loose. I loosened the top bolt that holds the adjuster to the block and the adjuster nut, and used a long extension to tap on the adjuster.
We saw some movement and felt that the chain was tight! Not drum tight, but certainly way tighter than it was before. I only tightened the top nut, then reassembled, re-re-re-re-relashed the valves, and then once again had my buddy spin the engine while I snugged up the adjuster nut. I should say that the bike had been starting somewhat hard it's whole life, but when I hit the start button this time the bike did not hesitate to fire immediately while cold.
But the rattle is still there. We are at a loss, I'll probably try and knock the tensioner around some more, get some oil/lube on it and see what that does, but any advice would be great! I'll post pictures at some point.
TL;DR: I can't for the life of me get the cam chain on my 1981 cb650 to tighten/stay tight.
Thanks!
