curious clutch config. on Ugly Betty

[Wilf]

When I first started work on this bike (1963 Super Hawk with 1965 engine #1001528) I opened up the clutch, separated and cleaned the stuck plates, noted the absence of plate stopper wires and then re-assembled everything the way it came apart. After riding for 150 miles I have some concerns about the clutch: some clutch drag, difficulty finding neutral, occasional clutch slip when taking off and what I consider a hard pull on the clutch lever.

I decided to re-visit my clutch to install the 2 wire stop rings (thanks, rrietman) and take notes and measurements this time. The photos should help with what I saw:

-dings on the left crankcase cover made by the vanes on the clutch pressure plate (no photo)
-evidence of grinding/sanding on the outermost faces of the clutch outer splines...?
-6 clutch plates--5 are thin, 1 is thick, and the thick one is the second one out from the engine
-5 friction discs--3 of them (stamped with a number 3) have what I think is an aluminum core and two are entirely fiber
-the clutch springs have white paint on one end

My measurements:

-3 clutch springs are 32.45 mm free length, and the 4th is 32.80
-the 5 thin metal clutch plates are well within flatness specs, but thicknesses are 1.58-1.61 mm
-the thick metal clutch plate is 1.99 mm in thickness (3rd from the right in the pic)
-the 'all fiber' friction discs are 3.95 mm and 3.77 mm (2nd and 6th from the right in the pic)

My guesses:

-the thick metal clutch plate should go closest to the engine
-the outermost plate which contacts the pressure plate should be a friction disc
-the friction discs should all be 'all fibre' or all 'metal core'
-my metal plates need replacement, as the wear limit is 1.60 mm or less

My questions:

I have no idea what a PO may have done to this clutch, and without part numbers stamped on the clutch parts I really don't know what clutch center, outer, plates and friction discs I have. I'm thinking I should replace the metal clutch plates and the friction discs, but with so many clutch changes over the years, I'm at a loss as to what and how many I should replace.

I'm hoping that someone with clutch expertise is willing to identify what I have and offer solutions.

Thanks for enduring a long post.

Wilf

[LOUD MOUSE]

The clutch parts ya show are a Mixed Batch and they were installed wrong for sure.
Can ya cll me?. ...............lm

When I first started work on this bike (1963 Super Hawk with 1965 engine #1001528) I opened up the clutch, separated and cleaned the stuck plates, noted the absence of plate stopper wires and then re-assembled everything the way it came apart. After riding for 150 miles I have some concerns about the clutch: some clutch drag, difficulty finding neutral, occasional clutch slip when taking off and what I consider a hard pull on the clutch lever.

I decided to re-visit my clutch to install the 2 wire stop rings (thanks, rreitman) and take notes and measurements this time. The photos should help with what I saw:

-dings on the left crankcase cover made by the vanes on the clutch pressure plate (no photo)
-evidence of grinding/sanding on the outermost faces of the clutch outer splines...?
-6 clutch plates--5 are thin, 1 is thick, and the thick one is the second one out from the engine
-5 friction discs--3 of them (stamped with a number 3) have what I think is an aluminum core and two are entirely fiber
-the clutch springs have white paint on one end

My measurements:

-3 clutch springs are 32.45 mm free length, and the 4th is 32.80
-the 5 thin metal clutch plates are well within flatness specs, but thicknesses are 1.58-1.61 mm
-the thick metal clutch plate is 1.99 mm in thickness (3rd from the right in the pic)
-the 'all fiber' friction discs are 3.95 mm and 3.77 mm (2nd and 6th from the right in the pic)

My guesses:

-the thick metal clutch plate should go closest to the engine
-the outermost plate which contacts the pressure plate should be a friction disc
-the friction discs should all be 'all fibre' or all 'metal core'
-my metal plates need replacement, as the wear limit is 1.60 mm or less

My questions:

I have no idea what a PO may have done to this clutch, and without part numbers stamped on the clutch parts I really don't know what clutch center, outer, plates and friction discs I have. I'm thinking I should replace the metal clutch plates and the friction discs, but with so many clutch changes over the years, I'm at a loss as to what and how many I should replace.

I'm hoping that someone with clutch expertise is willing to identify what I have and offer solutions.

Thanks for enduring a long post.

Wilf

[Wilf]

Thanks lm,

I was hoping you would respond, and yes, I will try calling you tomorrow mid-morning if that works for you.

Wilf

[LOUD MOUSE]

Ya bet. .....lm

Thanks lm,

I was hoping you would respond, and yes, I will try calling you tomorrow mid-morning if that works for you.

Wilf

[Wilf]

After a very informative conversation with lm yesterday we have concluded the following:

-the clutch center and outer are early 6-plate
-the thick plate should indeed be innermost
-the friction discs are an unworkable mix of early all fibre and later metal core versions
-the 6th (outermost) plate doesn't belong--the pressure plate should work against a friction disc

I will post a new pic when lm's replacement parts arrive (maybe in Christmas wrapping paper...)

Thanks Ed,

Wilf

[LOUD MOUSE]

I have the parts gathered.
Give a call. ............lm

After a very informative conversation with lm yesterday we have concluded the following:

-the clutch center and outer are early 6-plate
-the thick plate should indeed be innermost
-the friction discs are an unworkable mix of early all fibre and later metal core versions
-the 6th (outermost) plate doesn't belong--the pressure plate should work against a friction disc

I will post a new pic when lm's replacement parts arrive (maybe in Christmas wrapping paper...)

Thanks Ed,

Wilf

[Wilf]

I finally buttoned up my new clutch today--it took some work, but I think it will be a big improvement.

The first pic shows the replacement parts: pressure plate, friction discs, clutch plates and center from lm, and the 2 plate stopper wires from rrietman--thanks guys!

The installation was going great until I couldn't fit the snap ring into the groove on the drive shaft. There just wasn't enough groove for the ring. I compared my old clutch center to lm's replacement, and after some measuring, confirmed that the spline depth on my center had been reduced by a second 'relief cut'. The red marks show where I decided to machine the new center, reducing its thickness at the spline by about .025". You can see the lack of sufficient groove for the retainer ring on the drive shaft.

The newly machined relief on the replacement center looks awful, but that's mostly glare and camera flaw! The last pic shows my new clutch pack installed and ready to button up.

It's been an interesting month, but thanks to Ed and Randy, my shifting should be easier and more reliable.

Wilf

(I see that this post allows only 5 pics so the first one, showing all the new parts, will be posted separately)