Topic: 1974 CB750 Clutch Woes - Stalls When Going into Gear

[whitjonw]

I have been screwing with my clutch to no end. I have installed a new clutch cable and adjusted the clutch per the manual with no positive results. Does this sound like clutch plates sticking together and not separating ? The engine had set for a few years before I got it running last September. I put about 10 miles on it before putting it away for the winter and it had a tendency at that time to want to clunk into gear and stall out but not like it does now. I'm getting beyond frustrated !

Does this sound familiar to you guys ?

[Jimray23]

Does your bike have a center stand?

--------------------------------------------------
Jim
1979 kz1000b ltd
    stage 3 cams
    pod air filters
    4-1 open exhaust(no muffler)
    full rewire
    dyna-s ignition
    dyna 3 ohm coils

[Jimray23]

It could be the clutch push rod wore off on the tip or snapped in half

--------------------------------------------------
Jim
1979 kz1000b ltd
    stage 3 cams
    pod air filters
    4-1 open exhaust(no muffler)
    full rewire
    dyna-s ignition
    dyna 3 ohm coils

[whitjonw]

Does your bike have a center stand?

Yes, it does have a center stand. I have run the bike in gear while on the center stand while trying to diagnose this problem.

[flybox1]

If you're sitting on it, does it lurch forward when going into first/stalling?
If yes, clutch plates are sticking. Last oil change?

[whitjonw]

If you're sitting on it, does it lurch forward when going into first/stalling?
If yes, clutch plates are sticking. Last oil change?

Yes, that is exactly what it does. Last oil change was September of 2016 and no more than 10 miles put on it before winter and present.

[flybox1]

Re-adjust your cable, and change oil.  Those are your first tasks.
This happened to me repeatedly after winter slumber in Bel-ray Mineral 4T 20w50,  so I switched to Spectro 4 (not Golden) motorcycle 20w50, and it stopped after my first long ride.   Love it.  No more sticky plates

[whitjonw]

Re-adjust your cable, and change oil.  Those are your first tasks.
This happened to me repeatedly after winter slumber in Bel-ray Mineral 4T 20w50,  so I switched to Spectro 4 (not Golden) motorcycle 20w50, and it stopped after my first long ride.   Love it.  No more sticky plates

Readjusted the cable who knows how many times now but will do again and will see if I can get the Spectro 4. Thank you.

[Jimray23]

If you let it set a few months withoit oil in it, you may need to go in the clutch and get the rust out again

--------------------------------------------------
Jim
1979 kz1000b ltd
    stage 3 cams
    pod air filters
    4-1 open exhaust(no muffler)
    full rewire
    dyna-s ignition
    dyna 3 ohm coils

[scottly]

Start by adjusting the screw in the center of the clutch cover, with the cable adjusters loosened. You should be able to move the lever at the cover about 1/8 inch or slightly less with one finger. Once the screw is set, adjust the slack out with the cable adjusters, but don't rely solely on the "free" travel at the end of the handlebar lever; look at the cover lever when the handlebar lever is pulled in, and fine tune the cable so the cover lever starts to move at the smallest handlebar level movement that will still allow the cover lever to return to it's normal resting position when the handlebar lever is released.

[Bodi]

Is it possible someone replaced the clutch plates? Barnett clutch kits were popular as they provide increased torque capacity, BUT the clutch would often be seriously stuck - even when left overnight. Plus the friction material wore off rapidly with short plate life and a lot of fibrous crud in the oil: filters sometimes clogged to be bypassing within a couple of thousand miles.
I had a Barnett. I cut a plywood piece with a notch that fit over the left grip and held the clutch lever in. It wasn't long before I ditched their plates and installed OEM ones.

[seanbarney41]

the plates will usually unstick if you can get the bike moving and ride it around a little.  Try rolling down a hill, then clunk it in gear and go.  Or even just scoot it into motion with your feet.

[whitjonw]

Try rolling down a hill, then clunk it in gear and go.  Or even just scoot it into motion with your feet.

I've done that a few times prior to starting this thread and a couple since and still no luck. I've got the clutch center nut tool on the way as well as new gasket, springs, etc., so feel inclined to go in and have a look at this point.

[BomberMann650]

These don't have kickstand sensors do they?  The xj600 had me punk'd like that.

[whitjonw]

Re-adjust your cable, and change oil.  Those are your first tasks.
This happened to me repeatedly after winter slumber in Bel-ray Mineral 4T 20w50,  so I switched to Spectro 4 (not Golden) motorcycle 20w50, and it stopped after my first long ride.   Love it.  No more sticky plates

I picked up the Spectro 4 today, which I was amazed to find it locally, and will be changing the oil tomorrow. If this doesn't free it up in conjunction with putting several miles on it, I will go in and dismantle the clutch and check every thing out. Thanks for the tip.