Mystery clutch parts

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debby

debby

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My 850 isn't shifting very well. It acts as though the clutch is sticking or not releasing fully. I opened it up to have a look today.

First photo: clutch actuator arm. Does this look like a stock Commando actuator? Or is it the Atlas arm? The only photos I could find online were on atlanticgreen.com. From those, I think this is the Commando part but I'm not sure:

Mystery clutch parts


Clutch plates. I'm running a 750 clutch pack with an extra steel plate and a 750 pressure plate. Here is what the friction plates look like. The substrate is aluminum. Does anyone recognize these? I've never seen Commando plates quite like these. I'm guessing early Barnett? (the grabby ones):

Mystery clutch parts


I bought a set of Surflex plates to replace them, but they dont' fit! The splines don't match the clutch center, they're a little too "fat". I could make them fit with some filing and sanding, but it looks like a long tedious job. Has anyone run into that before? I thought Surflex plates were supposed to be good quality. Here's a photo:

Mystery clutch parts
 
Yes sure looks like 750 Cdo item I've diddled with too often but
can't see if the cable end has same cable slot of a Commando's.
Almost looks like half the cable slot piece is broken off in
this side view.
To make cable fitting a tad easier you can shave off almost
half the depth of the cable end.
Its too easy for this lever gizmo to drop down from the ball
pivot when you try to adjust the clutch pack screw on
other side of bike.

hobot
 
debby said:
My 850 isn't shifting very well. It acts as though the clutch is sticking or not releasing fully. I opened it up to have a look today.

First photo: clutch actuator arm. Does this look like a stock Commando actuator? Or is it the Atlas arm? The only photos I could find online were on atlanticgreen.com. From those, I think this is the Commando part but I'm not sure:

Mystery clutch parts


Clutch plates. I'm running a 750 clutch pack with an extra steel plate and a 750 pressure plate. Here is what the friction plates look like. The substrate is aluminum. Does anyone recognize these? I've never seen Commando plates quite like these. I'm guessing early Barnett? (the grabby ones):

Mystery clutch parts


I bought a set of Surflex plates to replace them, but they dont' fit! The splines don't match the clutch center, they're a little too "fat". I could make them fit with some filing and sanding, but it looks like a long tedious job. Has anyone run into that before? I thought Surflex plates were supposed to be good quality. Here's a photo:

Mystery clutch parts
Click to expand...

debby
from the top picture it does appear to be a commando BUT the difference is minor.

second picture
they do look like barnett plates and I don't like them.

third pic
they are the right surflex plate's and should fit the center BUT they can be a close fit on the spline. once you try them I think you will like them better than what came out.
also if you have access to a lathe you can machine the pressure plate and fit a fifth friction plate for more holding power.
 
Debbie, It's time to come around to a belt drive and a hydraulic clutch. Makes them work [and sound] like your ducati clutch. Jim
And where did you get the sureflex plates? I've been having trouble finding them.
 
I noticed the same thing with new Surflex plates and a new clutch center. I'm sure a little use will make it right.

Greg
 
bill said:
second picture
they do look like barnett plates and I don't like them.
Click to expand...

I've heard similar sentiments echoed here and there but am not sure where it comes from, since "upgrading" my old, slipping 750 clutch to the 850 set up w/5 Barnett friction plates, MK3 pressure plate & clutch rod seal the performance has been stellar. Lighter pull, no slippage, grabbing or sticking whatsoever.
 
Mine also works great with the Barnett plates, I wonder if something is wrong that they work good with ours Acadian? LOL. I run them in two bikes one dry and one wet and both bikes have great clutch action, I think maybe some bikes have warped steel plates that cause the grabbing they speak of, Don't really know but I had to go through quite a few steel plates to find nice flat ones. Someday I think I'll try these surflex plates to see what I am missing. :wink:
 
Most of the grief that Barnet clutches get comes from the old black Barnet plates. They were very aggressive. The plates Barnet sells nowdays work fine. Jim
 
Jim,

I"m piqued by the aggressive old black Barnet plates.
How would one find a new or used 850 set?

hobot
 
Hortons Norton said:
Mine also works great with the Barnett plates, I wonder if something is wrong that they work good with ours Acadian? LOL. I run them in two bikes one dry and one wet and both bikes have great clutch action, I think maybe some bikes have warped steel plates that cause the grabbing they speak of, Don't really know but I had to go through quite a few steel plates to find nice flat ones. Someday I think I'll try these surflex plates to see what I am missing. :wink:
Click to expand...

I'm thinking it may have something to do with gear oil migration onto the plates, the fiber Barnett plates may simply react poorly to oil contamination. With the clutch rod end seal, the problem is alleviated. Running ATF in the primary may also help too.
 
Hobot, Last time I spoke with Barnett [several years ago] they had both styles available. Black was the race compound and the white ones were standard. Haven't delt with them recently for Norton plates but I have used their Kevlar plates on Jap stuff with good results. Jim

I"m piqued by the aggressive old black Barnet plates.
How would one find a new or used 850 set?

hobot[/quote]
 
Ok thanks, I think Peels Barnett plates were black but forget as
been a few years last seen. I asked Barnett about pre oil before
install - was told - wet with ATF for a few minutes then wipe
excess off and sneak up on clutch engagements to avoid initial
chatter pattern seating.

Still tingling on narrowing my plates or buying RGM's to avoid
any hesitations in torque reaction.

hobot
 
I just installed surflex plates in my '72. There fit over the center was tight and I worked each plate back and forth to loosen the up a bit. Still had a little clutch drag shifting to 1st from N but now/ a couple hundred miles the drag has dissappeared and it drops right into 1st
 
Well, I got the Surflex plates fitted. I did a little filing on the edges of the teeth and got them all fitting nicely. It didn't take as long as I thought it might.

So, 5 oz. of ATF in the primary (not 7, per the Tech Digest), a belly full of Valvoline 90 wt. in the gearbox (I decided I was wasting my money buying that expensive Redline stuff!), primary chain adjusted, and it's pretty much ready to go. I'll finish it up tomorrow and hopefully get a test ride. The endless rain is supposed to be easing up for a while. It's about time.

Interesting idea ludwig has about machining down the steel plates. I can't do that myself, but I might pick up a spare set of steel plates and take them to the machine shop one of these days.

Jim, I'd love to get a belt drive on the bike one of these days, but with my luck I'd get one of the bad kits that needs a lot of machine work. Then I'd have to take bike and parts down to your shop so you could make them fit. That sounds expensive! :wink:

Debby
 
Come on down Debbie, I get cheaper if you use a broom while you watch. Jim
 
debby said:
Jim, I'd love to get a belt drive on the bike one of these days, but with my luck I'd get one of the bad kits that needs a lot of machine work. Then I'd have to take bike and parts down to your shop so you could make them fit. That sounds expensive! :wink:
Debby
Click to expand...

Good stuff doesn't come cheap! Debby do yourself a favour buy a Steve Maney belt-kit, guaranteed quality.
 
nortonspeed said:
debby said:
Jim, I'd love to get a belt drive on the bike one of these days, but with my luck I'd get one of the bad kits that needs a lot of machine work. Then I'd have to take bike and parts down to your shop so you could make them fit. That sounds expensive! :wink:
Debby
Click to expand...

Good stuff doesn't come cheap! Debby do yourself a favour buy a Steve Maney belt-kit, guaranteed quality.
Click to expand...
+1
 
I learned allot following this post.
I have allot of time on the smart end of a broom.
We have in Penna all your rain now Debby.
Someday I'll be doing a clutch job this was good info thanks everyone.
Marshal
 
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