Hi ya'll an happy turn back the clock day.
My 79 runs gr8 but the clutch is starting to slip, esp under throttle at speed. What is probably the most likely cure, adjustment or re-build. or maybe primary chain (just resized the sprocket)If it needs rebuilt I'll ride till Feb an the cold weather then do it but I could adjust it any time Whatcha all think Thanks Dusty

 

Hey Dusty,

My motto is try the easiest fix first. I have a 79 too, and itprobably just needs to be adjusted. It's a simple job and doesn't require any special tools. Just a sparkplug socket that will fit over the locking nut,a flatblade screwdriver that will fit through the hole in the socket, and a pair of channeloks to turn the socket.

Here are instructions from an Ironhead repair manual. Someone else on this forum may have different instructions???

Back off the cable adjuster until the adjuster is fully collapsed.

Remove the derby cover and set aside.

Loosen the clutch adjuster lock nut two turns.

Turn the clutch adjuster in until it seats against the clutch release. Seated means that it is touching but not pushing against the release. At this time the clutch lever should have very little play.

Back the adjuster out 1/2 to 1 full turn from seated. Repeat this several times to get all the play out.

Lock the adjuster nut down while holding the adjuster from turning.

Work the clutch lever several times before adjusting the free play at the cable adjuster. Adjust the free play to 1/16" to 1/8" as measured at the pivot. I usually add just a little slack as a personal preference.

Work the clutch several times to make sure operation is smooth and no binding in any part of the travel.

Install the derby cover after topping off primary oil if needed.

Perform a test ride and adjust the free play as needed to get the engagement and release points correct.
If you cannot adjust the clutch free play with the cable adjuster, the cable may be stretched or frayed. If the cable has been replaced, the wrong cable may have been installed.

A worn or warped clutch pack will often feel as if the adjustment is bad because it tends to make the release and engagement jerky. If after adjusting the free play you still have clutch operation problems it may be time to take a look at the clutch.

Good luck,

Aubrey

 

I'm not sure if your clutch is the same as my '76 was, but HD had some 3 different size spacers to take up the slack as the clutch wore. these are lengths of steel tubing that slip over the mounting studs to hold the pressureplate assembly at the right distance from the clutch basket.
If your clutch slips after you've adjusted it correctly (Try adjusting at least twice) you may need the next shorter spacers. Keep the old ones because you will need them if you ever replace the clutch disks.