CB650 Simple Service

[Ibsen]

http://home.online.no/~ivbekkel/CB650/H ... ervice.pdf

[rob]

Good article, thanks for the link.

I just read through it, and image 12, dealing with cam chain tensioner adjustment says, simply let the engine idle and then slacken the nut, tension is taken up.

Should this be done with the engine idling? I've always done it with while turning the engine over with a wrench with the ignition cover off.

Rob

[cb650]

I used to do it with the wrench but know use the starter. Dont think I would do it running.




Terry

[Ibsen]

The last time I adjusted the cam chain I did it the same way as Terry. It worked very well.

[rob]

So let me get this straight. While using the electric starter to turn the engine over, you loosten and tighten the cam chain tensioner nut? You set the igntion switch to off I presume to stop the engine from firing.

I went for a 100km ride last ngiht and there seems to be a good amount of cam chain and valve noise coming from the engine so I want to get this sorted out.

Thanks,

Rob

[Ibsen]

That is correct Rob. That's the way I did it, with the kill switch in the OFF position.

[Nate]

That is correct Rob. That's the way I did it, with the kill switch in the OFF position.

The process you mention Isben is what i thought of first when i read about adjusting the cam chain tensioner. I put a post on the SOHC4 board and was told that the starter would put to much load on the tensioner. But then the the article at the top of the post says while idling Now i'm officially baffled on how to go about it ???

[Volker_P]

There are many different ways to success and usually you should get a good tension either by hand turning or doing it at engine idle. If not, probably your tensioner is stuck, bent or misinstalled or the chain is lengthed to its limit. If you have doubts on your cam chain, remove the top center engine cover and check cam chain tension with a screwdriver. Turn engine by hand to see whether chain slack depends on position. Thats the way to really know what you have.

[Ibsen]

The problem with following the procedure in the workshop manual is that it's very difficult to maintain a pressure on the crankshaft with a spanner if you are to turn it at the same time as you are tightening the adjuster bolt. One of the English members on the SOCH4 forum, Bryanj a former Honda mechanic, posted in another topic about this issue that he never turned the crankshaft, he just put pressure on the spanner clockwise and maintained the pressure as he loosened the adjuster nut so that the spring on the tensioner unit would take up the slack in the chain, and then tightened the nut again. If you don't feel comfortable with using the starter motor for turning the engine, that is the method I would suggest.

[Nate]

I personally wasn't overly concerned about using the starter to turn it. I figure if the chain is going to go it's going to go wether I use the starter and kill it now, or it goes while i'm riding down the road. I'd prefer it to go at home so i'm not stuck someplace

[Nate]

So i dug into the bike today to adjust the cam chain tensioner. I tried the starter method first, loosening the bolt and then tightening it back while turning the starter on. When i restarted the bike after i had a hell of a racket coming from the top end of the motor. So i guessed my adjustment didn't work out to well. I tried it a couple more times and the rattle got less but still more than i had to begin with.

At this point the profanity was a full tilt, so i thought i'd try the method from the simple service manual with the engine idling. It worked like a charm, also the benifit is you can actually hear the chain tighten, or i guess not hear the rattling anymore. I guess my chain will be good for a bit longer