Should I alternate the clutch plates on an 850 Commando (2011)

I am helping my friend replace the worn clutch plates on his 1974 850 commando daily rider. His cluth started slipping a week or so back. When we romoved the old plates from the clutch housing I noticed that the previous owner alternated the plates bronze then composite then bronze then composite etc. We purchased a new set of Barnett plates from MAP last week a total of 5 I believe. Should I put all Barnetts back or alternate them like the [revious owner?? The steel plates look pretty good but I told him to take off all burrs and get everything real clean. Should I scuff the metal plates a little???? I have been told all Barnets can be a bit grabby and he doesn't want that. Anyone have any suggestions as to what to do??? As alway thanks so much for all the help---Mark Cigainero

Mark
I use the Barnett and steel plates alternating only and never have a problem. Grabby clutch could be a warped plate. Make sure they are all flat. Lay them on a piece of glass or surface plate and make sure they are flat.
You can also add a steel plate at the top of the stack, just before you put the pressure plate in to make the clutch release pull much easier.
Just looked this up last night as I am doing a friends 850.
http://www.oldbritts.com/ob_clutch_info.html

I'd suggest trying the new Barnett plates by themselves, adjusting the stack height with plain plates until you can just fit in the pressure plate under the circlip. If the Barnett plates still slip I'd try Type F (Ford) transmission fluid before tearing the clutch apart again--it seems to help slipping clutches. Those 850's make a lot of torque at low rpms.


Tim Kraakevik
kraakevik@voyager.net
'72 Combat, '74 850 RH10

I'd suggest trying the new Barnett plates by themselves, adjusting the stack height with plain plates until you can just fit in the pressure plate under the circlip. If the Barnett plates still slip I'd try Type F (Ford) transmission fluid before tearing the clutch apart again--it seems to help slipping clutches. Those 850's make a lot of torque at low rpms.

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Tim's review is how I do it and works a treat. Only thing I can add is that Barnett's says to first soak in ATF then wipe off to leave a film to avoid chattering on first bedding in with light use. Mix and match type of plates is a non issue except for nicer clutch action by getting stack height in sweep spot, which is when stack just does allow spring to slip in groove no forcing and no slack. Ahhh.

So, to achieve optimal stack height I could add yet another steel plate to help achieve an optimal stack height while achieving an even and smoother pull on the clutch lever?
If this is so, could I add one more steel plate (one of the clean previously used steel plates that I removed?) to my newly purchased Barnett assembly (new steel and friction plates) to gain optimal stack thickness?

start by putting in a steel plate, then a slightly oiled Barnet (dry they can disintigrate and shell off powerder quickly)
then steel then Barnet etc until you have them all in ending with a steel plate and then press the pack in good to leave some room
to put the pressure plate in firmly while an assistant feeds the big circlip in place
release the clutch tool and screw in the big slotted bolt until it seats and then back it out 1/2-3/4 of a turn and tighten the nut, good!
this all assumes you have not allowed the lifting arm in the gearbox to fall down of course

Realize that various thicknesses of pressure plates in alu, available from the oldest knowledgeable vendors, if ya know to ask - To help get stack, just right for ease of clutch lever holding/feathering and WOT clutch drop lock up engagement. Tire should slip before clutch, duh. Best if stack just allows the spring to slip in groove w/o much or any pressure resistance to seat and slip in the lock ring. If pressure plate has slack behind it then will want to have various plates, worn or machined to mix/match thicknesses on hand or just have to put up with best ya got till then. If clutch holds ok with steel against steel plate, go for it, if not, read above again. Once ya get it best ya can, take apart to measure stack to report back on what it was, to get respect here on how ya solved. Clutch should feel like modern compound bow, once drawn, effort is reduced to easy hold till time to release at target heart. Oh yeah if no Sprag gear to nurse, try Ford type F ATF in primary to forget about slicky plates to clean. The F stands for its allowing clutch Friction bands/plates to function grippy to slippy no problemo, no cleaning ever needed again. Barnett Clutch Inc. tech's say their new plates should be wet with ATF, not dry nor with ordinary gumming primary oil to prevent chatter on new seating in.

The Titanic had alternating Barnett and bronze plates between the steels. I removed the bronze plates and replaced them with some Barnetts I had in the bonepile. The primary was gooed on with blue RTV, so obviously some amateur ham-fist put the clutch pack in that way. For what reason, I have no clue.

the reason for the mix of plates goes back to the black barnett's. they were WAY to aggressive and known to break gearbox's so a mix was done to calm it down.

Danno said:

so obviously some amateur ham-fist put the clutch pack in that way. For what reason, I have no clue.

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