Topic: Yet Another CB500 Clutch Question

[Dr. Frankenstein]

I'm working on this 1972 CB500 Four, and can't seem to get the clutch cable dialed in; I thought I had it adjusted right, but something is amiss because when I try to pull the clutch in, it just stops, and won't do that little 'give' you feel when you pull in a normal one...pull the clutch lever and it feels like it won't go any farther - did I have it adjusted too tight?? it still has the original pushrod, and the ball in the adjuster, and I thought I had it yesterday but the whole clutch action seemed too 'weak' or something so of course I had to keep screwing with it.

I'm using a new clutch cable that is the same length as the old one; with the clutch side cover on, I can pull in the clutch at the handlebars, but the lifter itself only moves slightly - it's loose/it will go in and out, probably about 5 mm - but when the engine is buttoned up and you pull the clutch in, it's like the clutch lever just STOPS, and won't go any further. The clutch plates themselves are free - I cleaned them a while back (3 or 4 months ago), but do they get sticky again over time? I'll clean them again and see if that does anything... 

Also, I am torquing the clutch plate bolts to what the book says - 5.8–7.5 ft-lbs - would that have anything to do with it?

From what I have gathered though, these early 500 clutches seem to be a bit problematic - I'm assuming my problem is something I'm doing (or not doing!), but I wanted to field this question and see what you guys say.

[bryanj]

Torque has no effect adjustment of mechanism has a big effect and there is a bulletin on how to, that is the big round adjuster in the sprocket cover

[Dr. Frankenstein]

Hi Bryan - Yes, I know, I was following those instructions - loosening the bolt, turning the adjuster clockwise until a slight resistance is felt, then back it off an eighth of a turn and tighten the nut - but it just felt weird, it wasn't hard at all to pull the clutch lever in. Maybe I was tightening it too hard...? Do you know the link for the bulletin?

[bryanj]

Somewhere in a service letter there is a procedure with the modified adjuster that has a small notch on one end of the big slot which has to be within a certain position on the circumference, if i can find it i will copy it for you.

NOTE:- there are both sevice bulletins and sevice letters which are different

[Dr. Frankenstein]

Huh - yes, I'd like to see that. As far as I know though my adjuster is not modified...is that common on '72 JDM 500's?

[bryanj]

It was not a recall just a mod ifcuztomer complained

[Dr. Frankenstein]

Just out pf curiosity, I found two different torque settings for the CB500 clutch bolts: the internet says 7.2 - 10.1 Ft lbs, while the actual CB500 manual I have says to torque the clutch bolts to 5.7 - 8.6 Ft lbs... I googled 1972 CB500K, but could that larger torque value be for a 550?

Using the first number, I set the clutch bolts on my 500 to a median of 8.4 Ft lbs before I discovered the 5.7 - 8.6 value; what kind of difference will this make as far as the clutch is concerned? 

Also, since I set the torque on the 1972 CB500 to 8.4 Ft lbs, it is in spec, albeit on the outside edge of the torque values for that bike - would that make it harder to pull the clutch lever? (I would assume so...)