1978 Special with an 81 clutch??

[danfr]

Hey guys,

I have a new to me 1978 XS650 Special. I couldn't for the life of me get the clutch to disengage. I removed the clutch cover and found tie wire between a friction plate and steel plate!

So I completely disassembled the unit, and am about to reassemble the clutch with a set of used steel plates that I sanded down (the steel plates that were in there, had some serious heat marks).

The problem is that I noticed my clutch assembly completely different than what should be on my 78.

I did find the proper exploded diagram to what I have in my XS but now I'm having trouble getting everything back together in the right order. I'm hoping someone can confirm my order:

Installing into the basket..
1)Smaller ring first. Smaller being that it has a smaller O.D. It also has a lip. Like an L-shape profile and the L facing out (flat side facing in)
2)Cupped steel ring. Small diameter of ring facing in, large diameter out
3)1st steel plate with the teeth that engage the inner clutch hub (or whatever it is called)
4)Skinny wire, cir clip thingy.
5 and onwards) normal stacking sequence of clutch.


I also had a washer fall out when I removed the clutch cover. Is there a washer between the cir clip for the kickstarted and the outer clutch cover?


Cheers Dan

 

[5twins]

Yes, it sounds like you have the damper set-up assembled correctly on the clutch hub. The one thing you'll need to check is the steel plate thicknesses. The one that goes at the bottom and is locked in by that retaining wire is slightly thicker than the others @ 1.6mm. All the other steel plates should be 1.4mm thick.

Yes, there is often a shim washer on the kicker shaft. It has a tendency to cling to the cover when you pull it off and then fall out like yours did.

 

[danfr]

Yes, it sounds like you have the damper set-up assembled correctly on the clutch hub. The one thing you'll need to check is the steel plate thicknesses. The one that goes at the bottom and is locked in by that retaining wire is slightly thicker than the others @ 1.6mm. All the other steel plates should be 1.4mm thick.

Yes, there is often a shim washer on the kicker shaft. It has a tendency to cling to the cover when you pull it off and then fall out like yours did.

Great thanks for the reply. I'll pull out the callipers and look for the thicker steel plate that goes in first.

Couple more questions:

I noticed one cork friction plate that had steel on one face of it. Is that the first friction plate that should be installed after the clip?

How does that clip not cause uneven wear. the two ends of the wire clip together and overlap. I would imagine that would create a high side, no?

I posted a video just now of the inner basket and it looks to be worn unevenly. Should I consider replacing?

Thanks for your help! Hopefully this information will help someone in the future!!

 

[XSLeo]

That wire doesn't hook together that way, See the grooves the wire fits in, between two of the ridges along that groove you will find a hole. The ends of the wire push through the hole. This lets the wire fit into the groove all the way around the hub.
There are a few other things you can do while you have the clutch apart that will improve it a bit.
As you said you sanded out the burn marks, I did this with a coarse sand paper, like 150 grit. This coarse paper removed all the color and roughed up the surface.
If you look closely at the steel plates you can see that one side has a sharp edge, the other side a slightly rounded edge. This comes from the steel plates being punched out of sheet steel. This leaves a slightly rounded edge and a slightly sharp edge.
As I sanding the color off I also sanded that sharp edge a bit, just enough to break the sharp edge. Make it look like the rounded edge. This will let the plates slide on the hub better. That sharp edge can dig into the hub, binding things a bit.
The steel part of the fiber plates are stampede too. They can be touched up too.
Leo

 

[danfr]

That wire doesn't hook together that way, See the grooves the wire fits in, between two of the ridges along that groove you will find a hole. The ends of the wire push through the hole. This lets the wire fit into the groove all the way around the hub.
There are a few other things you can do while you have the clutch apart that will improve it a bit.
As you said you sanded out the burn marks, I did this with a coarse sand paper, like 150 grit. This coarse paper removed all the color and roughed up the surface.
If you look closely at the steel plates you can see that one side has a sharp edge, the other side a slightly rounded edge. This comes from the steel plates being punched out of sheet steel. This leaves a slightly rounded edge and a slightly sharp edge.
As I sanding the color off I also sanded that sharp edge a bit, just enough to break the sharp edge. Make it look like the rounded edge. This will let the plates slide on the hub better. That sharp edge can dig into the hub, binding things a bit.
The steel part of the fiber plates are stampede too. They can be touched up too.
Leo

Thanks for the reply Leo! Good to know about the clip. I'm guessing that the previous owner used tie wire as a replacement for the clip and it broke free and cooked my plates.

Do you know if that cork plate with the steel should be first in with the steel facing in? Or perhaps the last cork plate with the steel facing out?

 

[XSLeo]

I have had a few of these clutches apart. Not a lot, only 4 or 5. Never seen a fiber plate like that one. It looks like the wire was out of place and ground away the fiber.
I would get a different fiber plate. I picked up a whole clutch for around $10 on Ebay.
Leo

 

[danfr]

I have had a few of these clutches apart. Not a lot, only 4 or 5. Never seen a fiber plate like that one. It looks like the wire was out of place and ground away the fiber.
I would get a different fiber plate. I picked up a whole clutch for around $10 on Ebay.
Leo

Check this 70-73 clutch assembly out: Part number 6 is "Friction Plate 1" with a quantity of two. Part number 5 is "Friction Plate" with a quantity of 4.

the plot thickens.....

 

[5twins]

The clutch plates in the '70-'73 clutches were different. Don't even look at them. They were thicker (3.5mm), won't work in the later clutches, and are no longer available anyway. The friction plate in your first pic is toast, totally shot. The friction plates have a metal core but should have friction material bonded to both sides of that. The friction material is all worn off that one side of the plate in your pic. You should probably measure the thickness of all your friction plates. They should be 3mm thick (new) but can be down to 2.7mm, that's the wear limit. Both sides of the friction plates should look like the drawing above, with little blocks of friction material all the way around.

 

[5twins]

Here's how the ends of that retaining wire snap through the hole in the hub ......

There are numerous holes through the hub for oil flow but only one (or maybe a couple) will be in line with the wire groove.

In your second pic above, the hole for the wire ends is two slots back from where you have the ends sitting.

 

[danfr]

Great! Thanks for all the info! I will pick up some new friction plates.


Cheers
Dan

 

[builder]

The clutch plates in the '70-'73 clutches were different. Don't even look at them. They were thicker (3.5mm), won't work in the later clutches, and are no longer available anyway. The friction plate in your first pic is toast, totally shot. The friction plates have a metal core but should have friction material bonded to both sides of that. The friction material is all worn off that one side of the plate in your pic. You should probably measure the thickness of all your friction plates. They should be 3mm thick (new) but can be down to 2.7mm, that's the wear limit. Both sides of the friction plates should look like the drawing above, with little blocks of friction material all the way around.

Ok so in saying that the 70-73 plates are no longer available what is the replacement parts to rebuild the older clutch packs ????????????? I have a 306 motor (72) that still has the original clutch pack in it and the funny rubber washers (never seen before) on the friction plates, I have a hydraulic clutch in it that I just got working right but find at certain times the clutch will either hang and slowly gain traction or just loose grip ?

 

[TwoManyXS1Bs]

Builder, try this thread:

http://www.xs650.com/forum/showthread.php?t=37358