Clutch pack height (2006)

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Read Fred Eaton's wonderful Norton notes and as i am setting mine up for the first time, I was wondering if setting the pack height to coincide directly under the circlip with the diaphragm fitted was the go. I have Barnetts fitted and by the looks of things I will need one more plain plate to get the height. Is this recommended?

Cheers Richard
 

Ron L

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RichardS,
Most assuredly, this will give a much lighter clutch pull. Since you have already seen Fred's site, you know that he sells five different thickness of plain plates. If you shim it too much you can get some slippage, but you want the spring to be just slightly convex when totally released.
It works, I have done three of mine and a couple others. I keep one of each of Fred's shim plates in the shop.
 
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I'm not sure whether to resurrect this old thread, but here is my new Sureflex 750 Commando clutch pack with 4 fiber plates, 3 steels and the pressure plate installed in the assembled hub/drum, and it looks awfully short in relationship to the circlip groove.

What am I missing here?

Clutch pack height (2006)
 
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I've been though this so tell ya best is diddling plates and thickness of pressure plate so diaphragm spring just slips into basket barely allowing spiral circlip to fit in. Then take apart and measure for your best clutch height delight. Should be like modern compound bows after break over can easy hold till time to release at target. W/o worn spares and various thicknesses of pressure plates you may beat brains out w/o just buying all new again. Btw new plates or new arrangement of plates should be wet with AFT (type F perfered) then wiped off some to prevent chatter till mated nicely. Barnnett's protocol not hobot pleased following their advice.
 
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Mine looks like it needs another steel to even get close. Would putting the extra steel be at the bottom, middle or under the pressure plate be preferred?
 
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I put extra steel at back of basket but if obvious that worn seem foolish not to just start new. Again real Nortoneers, before this forum existed, fudge by pressure plates not extra out of place steel or friction plates. Nothing bad to put steel plate in just not any respect if ya admit on forum like hobot.

Get up to speed here as Captain Norton site now defunct.
https://www.google.com/search?clien...67k1j0i46k1j0i131i67k1j33i160k1.0.CYasYQHe0Dk
 

L.A.B.

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I'm not sure whether to resurrect this old thread, but here is my new Sureflex 750 Commando clutch pack with 4 fiber plates, 3 steels and the pressure plate installed in the assembled hub/drum, and it looks awfully short in relationship to the circlip groove.

What am I missing here?


It's the height from the raised ring of the pressure plate plus the spring (adjusted 'flat' with the clutch tool) that you check the distance to the groove.

https://www.oldbritts.com/ob_clutch_info.html
Clutch pack height (2006)



The fact that the edge of the pressure plate in your photo is slightly lower than the shoulder of the drum suggests that it's perhaps slightly low, but certainly not excessive.

http://atlanticgreen.com/clutchpak.htm
http://atlanticgreen.com/ndnsclutch.htm
 
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It's the height from the raised ring of the pressure plate plus the spring (adjusted 'flat' with the clutch tool) that you check the distance to the groove.

https://www.oldbritts.com/ob_clutch_info.html
Clutch pack height (2006)



The fact that the edge of the pressure plate in your photo is slightly lower than the shoulder of the drum suggests that it's perhaps slightly low, but certainly not excessive.

http://atlanticgreen.com/clutchpak.htm
http://atlanticgreen.com/ndnsclutch.htm


There we go!! Thanks for this.
 

rvich

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Commando clutches are already heavy. I have to admit that it drives me nuts to think about adding another steel plate. I recently cleaned and adjusted my 750. I took a spare circlip and cut it in half so that it was a single layer instead of two and slipped it in between the circlip in the groove and the diaphragm. It is .041 inches and made a sudden and huge difference to my clutch without adding much weight to the whole assembly. I really think that developing a way to shim the diaphragm closer to the stack is worth the effort.

Russ
 
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Commando clutches are already heavy. I have to admit that it drives me nuts to think about adding another steel plate. I recently cleaned and adjusted my 750. I took a spare circlip and cut it in half so that it was a single layer instead of two and slipped it in between the circlip in the groove and the diaphragm. It is .041 inches and made a sudden and huge difference to my clutch without adding much weight to the whole assembly. I really think that developing a way to shim the diaphragm closer to the stack is worth the effort.

Russ - This is sheer genius. I just ordered a circlip for under $10 that I can cut to size. And the .041" gives me flexibility if adding a plain plate at .078"-.080" is too much. Also, I'll have half a circlip left over should i need it on my other Commando. As a note, and I apologize if this is old news, Fred Eaton is no longer grinding reduced thickness plates as it is too labor intensive.
 
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nortonspeed

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I took a spare circlip and cut it in half so that it was a single layer instead of two and slipped it in between the circlip in the groove and the diaphragm. It is .041 inches and made a sudden and huge difference to my clutch without adding much weight to the whole assembly.

The inevitable question is will the loose single layer circlip work it's way out of there ???
 

rvich

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First, the .041 turns out to be the circlip before cutting. So the shim is .0205. It still made a big difference. And it is cheap and fairly easy. I don't see why it would come out any more than the circlip itself as it fits into the groove and is still spring steel held in by its own tension.

If it needed to be wider than .0205 then it would be pretty much impossible to get the additional width into the slot and I wondered about using something like JB Weld to put pucks on the surface of the shim to push the pressure plate further toward the clutch stack. Now that sort of thing might come loose, so I am not sure of best idea here to get additional width.

I do apologize about the typo on the width of the shim I placed. Had I remembered this post or realized the mistake I would have corrected it.
 
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