Topic: 1973 CB750K Clutch Adjustment "3/4 of free play"

[34barab]

Just got the bike yesterday and want to check over a few things before I take it on the street.  To check the clutch adjustment, I've read that part of the manual (a few times), but reached a speed bump.  Then I tried searching the forum for "clutch" and then "clutch adjustment" but got nothing(?).  (Browsed and found a string about a 550 K, but the description doesn't sound the same.)  So at the risk of being repetitive, I have to ask about clutch adjustment on a CB750 K3.  In the manual I got as far as para d, where it says ".....so that there is approx 3/4 of free play at the clutch lever".  Does "3/4 of free play" mean 3/4 of an inch?  And I don't think the Clutch Adjusting bolt is supposed to turn after you tighten the lock nut?  Any help is appreciated.

[martin99]

Don't know where you get 3/4 from. This is how I've always done it-

Slacken off completely the adjustment at both ends of the cable, so the cable is not under any tension.
Loosen the locknut under the clutch cover. Turn the adjusting screw out a turn or two(so it is free), then turn back in clockwise until you can just feel the pressure of it getting tighter. Back it off 1/4 turn, and holding it in position tighten the locknut.
From the clutch cover end, take up the adjustment on the cable until you have about 3/8" to 1/2" freeplay at the lever - meaning you can pull the lever in by that amount before any resistance is felt.
Job done. Use the adjuster at the lever for fine tuning if needed.

[34barab]

I'll try that.  Regarding the Clutch Adjusting bolt: in the attached pic, the smaller nut (locknut) tightens against the larger nut after you have 3/8" to 1/2" free play at the lever.  Should you be able to turn the clutch adj bolt after you tighten the lock nut?  Logic tells me no.  And does adjusting the knurled knob at the lever allow you to change whether the clutch grabs high or low?  Thanks.

[martin99]

What your pic is showing there is the threaded portion of the cable outer going into the case. It is not the 'adjusting bolt' as you term it. You need to remove the kickstarter, followed by the chrome cover behind it. In there you will see the adjuster, which is a stud with a locknut. After you have slackened your cable both ends, hold a screwdriver in the slot on top of the stud while you loosen it's locknut. Turn the stud out a couple of turns, then back in until you feel it make contact, then back a quarter turn. Holding it in that position with the screwdriver, tighten the locknut.

The lever is for fine adjustment, but in reality there is not a lot of leeway anyway. I have always found these clutches bite quite early. If you follow this procedure, and your back wheel isn't turning when in neutral on the mainstand, you're all good.

[evanphi]

and your back wheel isn't turning when in neutral on the mainstand, you're all good.

when the oil is warmed up.