Clutch problems

’73 850

I need a little guidance.
To make a long story short: my clutch broke. Got stranded.
Yesterday, within 30 miles, I had to adjust my clutch lever every 10 miles or so as slack kept developing, and the plates weren't really opening; then the cable broke as I pulled over to fiddle with it.
Opening the primary side today bronze bushing particles immediately started dripping out and I have a wildly wobbly basket (lots of orbital moment on the shaft with some play toward and away -- outward and toward the gearbox).
I’m unclear of the layout of parts, however (and what’s “gone”).

This is what I have…




I’m assuming a bushing goes where I'm pointing a stick (…which has vanished altogether – though I haven’t looked at the “back” of this assembly from the gear cluster side). But to be sure I’m reading this right, 17 goes there?, per this:



…the 17 on the right? as there are two 17. (And, yes, I’ll pull the transmission and go through all of it, but I’m just trying to get my bearings straight.) (...Pun intended.)

Also, there's a clip here, just in front of the stick. What is this clip supposed to retain?... the missing sleeve bush? it seems like there would still be a gap there.

The Haynes manual I’m referring to says it holds in a clutch spacer and shims, but pulling the basket/ chain and crank sprocket together, what one might take as “spacer” and “shims” fell from behind the basket, implying they weren’t retained. Nor do they slip back over the clip. (Also, in the diagram, I don’t see any circlip on the mainshaft. It’s only referred to in the text.) Does this clip "retain" the spacer and shims outboard from the sleeve?

This is what fell out:



I don't know these clutches, so your help would be appreciated. Thanks.

Start at the primary. Do you have pictures of that? Clutch basket. Chain or belt system.
would be good to know.
Cheers,

tom

CanukNortonNut said:

Start at the primary. Do you have pictures of that? Clutch basket. Chain or belt system.
would be good to know.
Cheers,

tom

Click to expand...

Yes, chain.

Well - to start, the bushings, #17, are pressed inside the sleeve gear, #16. They do not sit where you are pointing.

Like CNN said above, without seeing the clutch, it is hard to diagnose. Could it be that just your clutch cable stretched and broke? That happens from time to time.

The circlip is outboard from where your stick is pointing. The parts that fell out are the stepped washer and shims that sit between the clutch basket assembly and the circlip. The counterbore in the stepped washer fits over the circlip and keeps it from opening up and dislodging.

Having clutch material floating around in you primary oil is not unusual either - the bronze particles that you were referring to.

Derek Wilson said:

Well - to start, the bushings, #17, are pressed inside the sleeve gear, #16. They do not sit where you are pointing.

Like CNN said above, without seeing the clutch, it is hard to diagnose. Could it be that just your clutch cable stretched and broke? That happens from time to time.

The circlip is outboard from where your stick is pointing. The parts that fell out are the stepped washer and shims that sit between the clutch basket assembly and the circlip. The counterbore in the stepped washer fits over the circlip and keeps it from opening up and dislodging.

Having clutch material floating around in you primary oil is not unusual either - the bronze particles that you were referring to.

Click to expand...

I understand the sleeve would be pressed in. But your saying that, that bush (#17) would not be visible where I am pointing?

The material found was absolutely bronze particles. I'm familiar with opening cases and finding just that, then a deteriorated bush some where. It was excessive.

I thought at first it was just the cable (the wire, pulling and eventually slipping through the nipple) so I stripped out the cable, took a bus home, soldered a new lever end nipple and drove back. It snapped again. The basket was "locked up."

JCP said:

I understand the sleeve would be pressed in. But your saying that, that sleeve (#17) would not be visible where I am pointing?

The material found was absolutely bronze particles. I'm familiar with opening cases and finding just that, then a deteriorated bush some where. It was excessive.

I thought at first it was just the cable (the wire, pulling and eventually slipping through the nipple) so I stripped out the cable, took a bus home, soldered a new lever end nipple and drove back. It snapped again. The basket was "locked up."

Click to expand...

Also, that washer that fell out, isn't stepped. Not that i'm saying it shouldn't be, just that, mine isn't. But I follow what your saying here.

JCP said:

’73 850

I need a little guidance.
To make a long story short: my clutch broke. Got stranded.
Yesterday, within 30 miles, I had to adjust my clutch lever every 10 miles or so as slack kept developing, and the plates weren't really opening; then the cable broke as I pulled over to fiddle with it.
Opening the primary side today bronze bushing particles immediately started dripping out and I have a wildly wobbly basket (lots of orbital moment on the shaft with some play toward and away -- outward and toward the gearbox).
I’m unclear of the layout of parts, however (and what’s “gone”).

This is what I have…


View attachment 81647

I’m assuming a sleeve goes where I'm pointing a stick (…which has vanished altogether – though I haven’t looked at the “back” of this assembly from the gear cluster side). But to be sure I’m reading this right, 17 goes there?, per this:

View attachment 81648

…the 17 on the right? as there are two 17. (And, yes, I’ll pull the transmission and go through all of it, but I’m just trying to get my bearings straight.) (...Pun intended.)

Also, there's a clip here, just in front of the stick. What is this clip supposed to retain?... the missing sleeve bush? it seems like there would still be a gap there.

The Haynes manual I’m referring to says it holds in a clutch spacer and shims, but pulling the basket/ chain and crank sprocket together, what one might take as “spacer” and “shims” fell from behind the basket, implying they weren’t retained. Nor do they slip back over the clip. (Also, in the diagram, I don’t see any circlip on the mainshaft. It’s only referred to in the text.) Does this clip "retain" the spacer and shims outboard from the sleeve?

This is what fell out:

View attachment 81649

nothI don't know these clutches, so your help would be appreciated. Thanks.

Click to expand...

JCP said:

’73 850

I need a little guidance.
To make a long story short: my clutch broke. Got stranded.
Yesterday, within 30 miles, I had to adjust my clutch lever every 10 miles or so as slack kept developing, and the plates weren't really opening; then the cable broke as I pulled over to fiddle with it.
Opening the primary side today bronze bushing particles immediately started dripping out and I have a wildly wobbly basket (lots of orbital moment on the shaft with some play toward and away -- outward and toward the gearbox).
I’m unclear of the layout of parts, however (and what’s “gone”).

This is what I have…


View attachment 81647

I’m assuming a sleeve goes where I'm pointing a stick (…which has vanished altogether – though I haven’t looked at the “back” of this assembly from the gear cluster side). But to be sure I’m reading this right, 17 goes there?, per this:

View attachment 81648

…the 17 on the right? as there are two 17. (And, yes, I’ll pull the transmission and go through all of it, but I’m just trying to get my bearings straight.) (...Pun intended.)

Also, there's a clip here, just in front of the stick. What is this clip supposed to retain?... the missing sleeve bush? it seems like there would still be a gap there.

The Haynes manual I’m referring to says it holds in a clutch spacer and shims, but pulling the basket/ chain and crank sprocket together, what one might take as “spacer” and “shims” fell from behind the basket, implying they weren’t retained. Nor do they slip back over the clip. (Also, in the diagram, I don’t see any circlip on the mainshaft. It’s only referred to in the text.) Does this clip "retain" the spacer and shims outboard from the sleeve?

This is what fell out:

View attachment 81649

I don't know these clutches, so your help would be appreciated. Thanks.

Click to expand...

nothing fell out. that thing in the image with the wood paneling pic... should be the cup spacer that goes over the cir-clip that you are pointing at with that big nasty stick of yours. shims are added to make sure the primary drive sprocket and the clutch socket are aligned. this is perfected by a straight edge. Just make sure it is aligned. That gets your chain in alignment.
Check that first.
Report back.
Cheers.
Tom

CanukNortonNut said:

nothing fell out. that thing in the image with the wood paneling pic... should be the cup spacer that goes over the cir-clip that you are pointing at with that big nasty stick of yours. shims are added to make sure the primary drive sprocket and the clutch socket are aligned. this is perfected by a straight edge. Just make sure it is aligned. That gets your chain in alignment.
Check that first.
Report back.
Cheers.
Tom

Click to expand...

Careful -- that nasty stick of mine was a gift from my family.

I think I understand the lay out of this now (though I don’t have that stepped spacer). Thanks.

Sorry JCP. I am being difficult.

the stick you are pointing at is the circlip that will get into alignment with the clutch sprocket
pack and align to the gearbox with the power take off. (Engine) All this needs to be alighned. That circlip should have a cupped spacer over it. The washer should have a undercut to fit over the circlip where your stick shows. Shims are added to align the system to be straight.
Hope that helps.
Cheers,
Tom

look for a cupped location spacer.

CanukNortonNut said:

look for a cupped location spacer.

Click to expand...

I was joking about the stick.

I found this posted.



My question is, is the bronze you see around the mainsheet in fact the bush I asked about (#17 from the illustration)? And is the space you see from where the circlip will sit (once pushed down the shaft) to the edge of the bush correct? Maybe an 1/8 of an inch?

JCP said:

I found this posted.

View attachment 81653

My question is, is the bronze you see around the mainsheet in fact the bush I asked about (#17 from the illustration)? And is the space you see from where the circlip will sit (once pushed down the shaft) to the edge of the bush correct? Maybe an 1/8 of an inch?

Click to expand...

Yes and yes
Have you checked with a thinner stick if theres a bush still in there?
It maybe your photo but the sleeve gear doesn't look central to the output shaft?
The spacer you show in picture 3 should have a recess inside to fit snug over that circlip

JCP said:

I think I understand the lay out of this now (though I don’t have that stepped spacer). Thanks.

Click to expand...

It should look like this with an internal step? Shims between the spacer and the clutch.

Quote from the NOC Commando Service Notes:

"Sleeve gear bushes are always coming loose-sometimes the outer bush moves inwards to the centre of the sleeve gear-then all you need do is to Loctite a now bush in the end. Leave the old one in and it will prevent the new one moving inwards, i.e. fit three bushes in your 750 a la 850. Sometimes the bush moves outwards and gradually mills itself away on the sharp edges of the circlip which locates the clutch. That's worse because eventually the bush disappears completely and all the pull of the back chain comes on the sleeve gear bearing. No wonder the bearings come loose. Often the first sign of sleeve gear bushes going -is striking "gold" in gearbox or primary drive oil, watch it! Here the answer is to buy two new bushes and a clutch location shim (060894 or 060895). Push both bushes-Loctited on the outside--into the sleeve gear the middle one stops the outer from moving in-and then put the shim loose on the shaft to avoid the bush wearing on the circlip even if it does move."

Later (Mk2/2A and M3) sleeve gears have a wire circlip inside the outer end of the sleeve gear (Mk3 has one at both ends) to prevent the bush from moving outwards.

JCP said:

View attachment 81649

.................Does this clip "retain" the spacer and shims outboard from the sleeve?

Click to expand...

Yes, and as noted the spacer locks over the circlip and the shims are for clutch drum to engine sprocket alignment, adjusted to ensure a straight run for your triplex chain.

And, sort of irrelevant after L.A.B.s post, but on the pre Commando short mainshaft gearbox on the shelf in my workshop I can see the phosphor bronze bush end maybe 1/16" in from the sleeve gear outer end.

If it is feeling like the lever has locked up, the cam that the cable fits into inside the transmission has likely slipped down out of position, quite common if the cable is disconnected and the clutch adjuster screw is removed to facilitate the use of the clutch spring compressor.

What do you have for a shop manual?

baz said:

Yes and yes
Have you checked with a thinner stick if theres a bush still in there?
It maybe your photo but the sleeve gear doesn't look central to the output shaft?
The spacer you show in picture 3 should have a recess inside to fit snug over that circlip

Click to expand...

I'll get in there today and pull the gear cluster out and see what's what, but yes, the output shaft is just floating there, so to speak. I can move it significantly, as if I won't find any remnant of a bush in there.

Sounds like a classic bikini wax...
(Sorry, couldn't resist)

L.A.B. said:

It should look like this with an internal step? Shims between the spacer and the clutch.

Motorcycle parts and spares for Norton motorbikes - Genuine Andover Norton Spare Parts - Andover Norton Motorcycles Parts - Original Andover Norton Parts

Motorcycle parts and spares for Andover Norton motorbikes: Andover Norton manufactures and supplies all Genuine Factory Spare Parts for Norton motorcycles built before 2002.

andover-norton.co.uk

Quote from the NOC Commando Service Notes:

"Sleeve gear bushes are always coming loose-sometimes the outer bush moves inwards to the centre of the sleeve gear-then all you need do is to Loctite a now bush in the end. Leave the old one in and it will prevent the new one moving inwards, i.e. fit three bushes in your 750 a la 850. Sometimes the bush moves outwards and gradually mills itself away on the sharp edges of the circlip which locates the clutch. That's worse because eventually the bush disappears completely and all the pull of the back chain comes on the sleeve gear bearing. No wonder the bearings come loose. Often the first sign of sleeve gear bushes going -is striking "gold" in gearbox or primary drive oil, watch it! Here the answer is to buy two new bushes and a clutch location shim (060894 or 060895). Push both bushes-Loctited on the outside--into the sleeve gear the middle one stops the outer from moving in-and then put the shim loose on the shaft to avoid the bush wearing on the circlip even if it does move."

Later (Mk2/2A and M3) sleeve gears have a wire circlip inside the outer end of the sleeve gear (Mk3 has one at both ends) to prevent the bush from moving outwards

Click to expand...

I'm guessing something like a "milling" situation happened. And I definitely struck "gold". What I find interesting was that I was just in there looking at the stator -- maybe three weeks ago -- and there was no sign of anything in the oil, so whatever happened, happened quick.

And thanks for the above. There's some ideas there to consider.

EstuaryBoy said:

Sounds like a classic bikini wax...
(Sorry, couldn't resist)

Click to expand...

I had a similar thought (and I wish the thing would just grow back on its own).