RGM belt drive clutch issue.

MLW

MLW

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I am in the process of setting up the stack height for the clutch for my new RGM belt drive kit to go into my Commando and ran into some issues. First I have tried emailing RGM and they haven't responded and when calling them I can hear them but they can't hear me. The issue started when assembling a 5 disc clutch pack into the new drum I had to force the retaing ring in place with pliers, I experienced ne such issues with the stock chain drive drum with the same clutch pack. Once assembled the spring was very much in a convex position as oppoesed to the correct slightly convex possition as indicated elsewhere in this forum. The spring does assume the correct position with the original chain drive drum. Investigating further, I compared the measurement from the bottom of the drum to the retaining ring groove. With the supplied 4mm plate at the bottom of the belt drive drum, the belt drive drum is 3mm less than the chain drive drum. The instruction say that the 4mm plate is in addition to the standard clutch stack but I can't see how it could fit with that difference in depth. Has anyone else run into this issue, am I avorlooking something. Any help would be appreciated.
 
MLW said:
Once assembled the spring was very much in a convex position as oppoesed to the correct slightly convex possition as indicated elsewhere in this forum.

The issue started when assembling a 5 disc clutch pack into the new drum I had to force the retaing ring in place with pliers,...
Click to expand...

Slightly concave position (normal for a standard clutch stack)? It should not be necessary to have to force the circlip into its groove under any circumstances.

MLW said:
The instruction say that the 4mm plate is in addition to the standard clutch stack but I can't see how it could fit with that difference in depth.
Click to expand...

" The first plate at the bottom of our belt drive drum would normally be 4mm thick, 3mm is OK but do not use 2mm as the first plate. An Average build for a Commando might be 1 x 4mm, 4 x 2mm, 4 x 3.6mm, 1 x 050014N at 5mm on teeth Equals 31.4 at drum."

Four 3.6mm friction plates not five (3.2mm?).


050014N is a special thin pressure plate.
"THIS PLATE IS DESIGNED FOR THOSE PEOPLE WHO WISH TO EITHER ADJUST CLUTCH PLATE STACK THICKNESS AND/OR REDUCE THE RECIPROCATING WEIGHT OF THE CLUTCH. BEING THINNER THAN THE STANDARD ALLOY PRESSURE PLATE, 050014.

MAX THICKNESS: .308" (TEETH .195")"
 

www.rgmnorton.co.uk

RGM BELT DRIVE 5 FRICTION PLATE CLUTCH COMPLETE, COMMANDO

RGMBDC5CL 5 FRICTION PLATE CLUTCH BELT DRIVE CLUTCH
www.rgmnorton.co.uk

RGMBDC5CL​

RGM Genuine
ONCE BEDDED IN IT MAY BE POSSIBLE TO INCREASE THE STACK HEIGHT BY CHANGING THE BACKING PLATE TO 4MM TO GIVE A LIGHTER LEVER. IF THE CLUTCH NEEDED TO TRANSMIT MORE POWER THEN THE STACK HEIGHT COULD BE REDUCED 1MM BY CHANGING THE BACKING PLATE TO 4MM AND REMOVING THE FIRST STEEL CLUTCH PLATE.
 
L.A.B. said:
Slightly concave position (normal for a standard clutch stack)? It should not be necessary to have to force the circlip into its groove under any circumstances.



" The first plate at the bottom of our belt drive drum would normally be 4mm thick, 3mm is OK but do not use 2mm as the first plate. An Average build for a Commando might be 1 x 4mm, 4 x 2mm, 4 x 3.6mm, 1 x 050014N at 5mm on teeth Equals 31.4 at drum.

Four 3.6mm friction plates not five (3.2mm?).


050014N is a special thin pressure plate.
"THIS PLATE IS DESIGNED FOR THOSE PEOPLE WHO WISH TO EITHER ADJUST CLUTCH PLATE STACK THICKNESS AND/OR REDUCE THE RECIPROCATING WEIGHT OF THE CLUTCH. BEING THINNER THAN THE STANDARD ALLOY PRESSURE PLATE, 050014.

MAX THICKNESS: .308" (TEETH .195")"
Click to expand...
I am using the thin pressure plate @ .105" for the 5 plate stack and I am using 5 3.2mm friction plates and my stack height is 31.2mm.
 
L.A.B. said:

www.rgmnorton.co.uk

RGM BELT DRIVE 5 FRICTION PLATE CLUTCH COMPLETE, COMMANDO

RGMBDC5CL 5 FRICTION PLATE CLUTCH BELT DRIVE CLUTCH
www.rgmnorton.co.uk

RGMBDC5CL​

RGM Genuine
ONCE BEDDED IN IT MAY BE POSSIBLE TO INCREASE THE STACK HEIGHT BY CHANGING THE BACKING PLATE TO 4MM TO GIVE A LIGHTER LEVER. IF THE CLUTCH NEEDED TO TRANSMIT MORE POWER THEN THE STACK HEIGHT COULD BE REDUCED 1MM BY CHANGING THE BACKING PLATE TO 4MM AND REMOVING THE FIRST STEEL CLUTCH PLATE.
Click to expand...
Using a 3mm first plate still doesn't account for the 3mm difference?
 
MLW said:
Using a 3mm first plate still doesn't account for the 3mm difference?
Click to expand...

Unfortunately, I don't have any measurements for the RGM belt drive clutch drum, only the original Commando drum.
RGM belt drive clutch issue.


According to RGM's picture, there are 6 plain plates (all the same thickness?) instead of the usual 4, one of which replaces the standard back plate and the other is the last plate under the alloy pressure plate. The thickness of the two additional plain plates would seem to (approximately) make up for the lack of the standard drum back plate.

The standard plain plates are approximately 2.0mm, with 5 friction and your .105" pressure plate should give an approximate stack height of 30.6mm (or 31.6 with a 3.0mm plate?), substantially more than the standard stack height quoted by OldBritts of 1.027"/ 26.08mm, however, that could be due to the RGM drum possibly requiring a different stack height to the original drum.

"Total clutch plate thicknesses (5 friction, 4 plain and 1 pressure) is: 1.027”"


With the diaphragm spring outer ring set 'flat' using the spring compressor and placed on the stack, if the outer edge of the spring partially covers the circlip groove then stack height is almost certainly too high so makes the retaining circlip difficult to replace.
 
L.A.B. said:
Unfortunately, I don't have any measurements for the RGM belt drive clutch drum, only the original Commando drum.
RGM belt drive clutch issue.


According to RGM's picture, there are 6 plain plates (all the same thickness?) instead of the usual 4, one of which replaces the standard back plate and the other is the last plate under the alloy pressure plate. The thickness of the two additional plain plates would seem to (approximately) make up for the lack of the standard drum back plate.

The standard plain plates are approximately 2.0mm, with 5 friction and your .105" pressure plate should give an approximate stack height of 30.6mm (or 31.6 with a 3.0mm plate?), substantially more than the standard stack height quoted by OldBritts of 1.027"/ 26.08mm, however, that could be due to the RGM drum possibly requiring a different stack height to the original drum.

"Total clutch plate thicknesses (5 friction, 4 plain and 1 pressure) is: 1.027”"


With the diaphragm spring outer ring set 'flat' using the spring compressor and placed on the stack, if the outer edge of the spring partially covers the circlip groove then stack height is almost certainly too high so makes the retaining circlip difficult to replace.
Click to expand...
With the diaphragm spring set at flat, it completely covers the circlip groove. I will order a 3mm backing plate from RGM and see if that helps. I also checked the diaphagm spring and found it to be warped and out of true by almost 2mm, maybe this is also contributing to the problem...
 
MLW said:
With the diaphragm spring set at flat, it completely covers the circlip groove. I will order a 3mm backing plate from RGM and see if that helps.
Click to expand...

I'm not sure I understand. The back plate would normally be riveted to the standard drum but I don't think that applies to the RGM drum and is why two additional (2.0mm?) plain plates are supplied with the kit.
andover-norton.co.uk

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
 
L.A.B. said:
I'm not sure I understand. The back plate would normally be riveted to the standard drum but I don't think that applies to the RGM drum and is why two additional (2.0mm?) plain plates are supplied with the kit.
andover-norton.co.uk

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
Click to expand...
The back plate on the RGM drum is not riveted on this design, it's just a loose plate.
 
MLW said:
The back plate on the RGM drum is not riveted on this design, it's just a loose plate.
Click to expand...

Yes that's what I thought. One of the additional plain plates appears to be used as the backplate so are the 6 belt drive kit plain plates all the same (2.0mm) thickness?
 
I’ve just fitted one. Mine has a five plate clutch and with the 4mm backplate it all fits and I have a nice light clutch. My friction plates are 3.2mm. If you are using a steel pressure plate you do not need a steel plate on top of the last friction plate. Do you have 3.6mm friction plates?
Dave
 
Looking again at the photo of the kit there are too many steel plates, I’m not sure if this is a reflection of what you have?

Dave
 
Dellis said:
Looking again at the photo of the kit there are too many steel plates, I’m not sure if this is a reflection of what you have?

Dave
Click to expand...

According to RGM's instructions: "For longevity aluminium pressure plates should have one of the [060]746 steel plates beneath them" which accounts for one of the two additional plain plates in the picture.

Dellis said:
I’ve just fitted one. Mine has a five plate clutch and with the 4mm backplate it all fits and I have a nice light clutch.
Click to expand...

According to RGM: "ONCE BEDDED IN IT MAY BE POSSIBLE TO INCREASE THE STACK HEIGHT BY CHANGING THE BACKING PLATE TO 4MM TO GIVE A LIGHTER LEVER."
 
Dellis said:
I’ve just fitted one. Mine has a five plate clutch and with the 4mm backplate it all fits and I have a nice light clutch. My friction plates are 3.2mm. If you are using a steel pressure plate you do not need a steel plate on top of the last friction plate. Do you have 3.6mm friction plates?
Dave
Click to expand...
I am using the 3.2mm friction plates.
 
MLW said:
I am using the 3.2mm friction plates
Click to expand...

...And, one 4.0 mm plain backing plate (although RGM says can be used after bedding in?) and five 2.0mm plain plates?
Steel or aluminium pressure plate?
 
L.A.B. said:
...And, one 4.0 mm plain backing plate (although RGM says can be used after bedding in?) and five 2.0mm plain plates?
Steel or aluminium pressure plate?
Click to expand...
I'm using a steel 0.105" pressure plate and four 2mm steel plates.
 
MLW said:
I'm using a steel 0.105" pressure plate and four 2mm steel plates.
Click to expand...
A 4mm backing plate seems too high.

A 2mm backing plate might be a better starting point in my opinion at least until the plates have "bedded in" as RGM says.
 
L.A.B. said:
A 4mm backing plate seems too high.

A 2mm backing plate might be a better starting point in my opinion at least until the plates have "bedded in" as RGM says.
Click to expand...
RGM advises a minimum 3mm backing plate and recomend against the 2mm plate but I will try a 3mm plate and see what that does.
 
MLW said:
RGM advises a minimum 3mm backing plate and recomend against the 2mm plate but I will try a 3mm plate and see what that does.
Click to expand...

Ok, although what RGM says below makes no sense (to me!) as the 3mm backing plate would seem to be what's supplied with the kit, not 4mm.
:confused:
www.rgmnorton.co.uk

RGM BELT DRIVE 5 FRICTION PLATE CLUTCH COMPLETE, COMMANDO

RGMBDC5CL 5 FRICTION PLATE CLUTCH BELT DRIVE CLUTCH
www.rgmnorton.co.uk
"ONCE BEDDED IN IT MAY BE POSSIBLE TO INCREASE THE STACK HEIGHT BY CHANGING THE BACKING PLATE TO 4MM TO GIVE A LIGHTER LEVER. IF THE CLUTCH NEEDED TO TRANSMIT MORE POWER THEN THE STACK HEIGHT COULD BE REDUCED 1MM BY CHANGING THE BACKING PLATE TO 4MM AND REMOVING THE FIRST STEEL CLUTCH PLATE."

I think RGM's stack height seems high because the backing plate is included which is not the case with the standard clutch stack height.
 
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