No matter of adjustment cluth still drags, do I need a new one?

[Daren]

Hello gentlemen,
Assume I have all of the cable adjustments properly taken care of,
so please rule that out. Brand new cable.
I have no idea what grade oil the previous owner filled the bike with,
he drained it because he thought the bike was being shipped and then
put new oil in it when I picked it up locally. But wrong oil is a slippage problem right?


First I unscrew the clutch adjustment bolt until it's rather loose, but not all the way so it falls out.
Then I screw it back in until I feel some resistance and back it off a little. But it's very little resistance,
I could go on tightening it. In this position I get nothing, the lever is slack and if I put it in first gear
the bike will not roll with lever pulled in.


But when I screw it in further it only makes the collar protrude and finally it bottoms out.
Even in this position with absolutely no play in the lever it still drags. I can just barely roll it
when I engage the clutch.
Can anyone tell me if this is a sign of a dead clutch?
Notice how in the last image the actuator arm is not resting on the collar.
In these images which one looks like the proper position?

thanks, Daren.

 

[dan1951]

Clutch is more than likely good, Looks like the problem is in the lifter assy.There are three steel balls that ride in a track that gives You the in and out movement to disengage the clutch. When You engage and disengage the cluch lever that shaft in the picture should move in and out.

 

[dirtdigger]

Biggest thing for dragging clutch is grooves worn in the inner clutch hub. The disks sit in the grooves and cant move far enough to completely disengage.

 

[Daren]

Biggest thing for dragging clutch is grooves worn in the inner clutch hub. The disks sit in the grooves and cant move far enough to completely disengage.

Clutch is more than likely good, Looks like the problem is in the lifter assy.There are three steel balls that ride in a track that gives You the in and out movement to disengage the clutch. When You engage and disengage the clutch lever that shaft in the picture should move in and out.

Thanks guys. I tighten the adjuster screw in all of the way until it is seated, while tightening the adjuster screw the collar protrudes out from the casing.
With absolutely no play at the lever, and the adjuster all the way in, the clutch still drags when I pull the lever.
The actuator does move in and out.




Either way if I have to get to the clutch ball assembly or the clutch lifter cam I have to drain the oil and get a new gasket.
That sucks. While I'm in there I guess it would be a good idea to just replace the plates. Cycle X has a good setup and comes with everything needed.

Any advice from the community?

 

[dirtdigger]

You dont have to drain any oil as the 750 is a dry sump motor...all oil is in the oil tank unless you have a bad check valve in the oil pump. With the bike on the kickstand any oil in the sump should be on the left side anyway. Always use a new gasket and NEVER use RTV silicone on any gaskets. Get it apart and see how the inner and out clutch basket look and send some pictures before you order any parts. I am guessing you have some deep grooves or maybe something else binding inside.

 

[Daren]

Thanks. I know it's dry sump but there is always some oil down in the case,
wasn't sure if leaning it over was good enough to avoid spillage.
I lightly spread motor oil on new gaskets, that's all they need. You can tell
an amateur build by how much silicone there is all over the engine, in and out.
I ran the bike for awhile to make some adjustments on the timing and carbs,
and the problem seems to have cleared up. I'm worried it may return while
out riding though. Will let you know.

 

[thughes0025]

I have a 1981 cb750 custom..my clutch won't disengage at all..new cable don't help..I opened the side cover their is oil in the engine but the bike has been sitting many years...I noticed my clutch basket itself is moving front to back like over 1/8 of an inch...I believe my whole basket is wore out but I'm not sure can anyone help..

 

[thughes0025]

I have a 1981 cb750 custom..my clutch won't disengage at all..new cable don't help..I opened the side cover their is oil in the engine but the bike has been sitting many years...I noticed my clutch basket itself is moving front to back like over 1/8 of an inch...I believe my whole basket is wore out but I'm not sure can anyone give further info..I do t believe my basket should move at all in and out but I'm new an not sure...I ordered a new whole set up..so any ideas let me know

 

[user8086]

Check your clutch basket... On most 750 models they are riveted...

 

[thughes0025]

Yeah..it is I believe it the problem...I got like an 1/8 of an inch of play in it

 

[user8086]

Check your clutch basket... On most 750 models they are riveted...

Yeah..it is I believe it the problem...I got like an 1/8 of an inch of play in it

Cool you can pick one up relatively cheap (used).. it's a common problem with those rivets especially after time.. what we also see is when you put your cover back on make sure your arm where your cable will connect to is pointing almost towards the rear tire... Not where you think it is going to end up or where it was when you pulled the cover off.

 

[thughes0025]

Thanks for the help..I got a new used one on the way..hopefully it fixes the ol'girl

 

[user8086]

New motor for cb750f

 

[thughes0025]

I pulled my old basket out the riveted gear on the back definitely has play in it...so glad I got a new one...thanks for the help guys

 

[user8086]

No prob

 

[Butscut]

I pulled my old basket out the riveted gear on the back definitely has play in it...so glad I got a new one...thanks for the help guys

Are you aware that you can repair that basket by drilling the rivets out, separating the gear from the basket exposing the (likely failed) rubber dampers. You then replace the rubber dampers and reassemble the clutch basket using bolts instead of rivets. It's a common repair and makes a big difference.