New clutch plates for a Mk3

p400

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I need to refresh my primary drive on a Mk3.
gear shift seal leaking
gear shift bushing seems loose.
I need to inspect the primary.
clutch seems grabby and wont allow first without crunch.
primary case seems to be seeping.
primary drain plug seems to pee on exhaust.

So, if cost is no object for clutch plates, what/whose clutch plate set would be my best choice?
Andover
Barrnett
Bonneville shop
RGM
eBay
Baxter
CNW


or others

sintered plates or friction material?


09.jpg
 
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p400

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looks like a sintered set from Andover would be about $400
But what kind of primary oil would be prevalent using sintered metal,
Would this oil be kind to the starter sprag


AndoverClutchCosts1.jpg
 

lazyeye6

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You need to inspect the whole primary. Many have had lifetime success with OEM scintered plates (they tend to rarely wear out). And the oil of
preference in a Mk3 would be the same as the engine oil (not ATF which doesn't work well with the auto chain tensioner)
The "crunch" may very well be a clutch hub which is notched, thus not allowing clutch plates to separate as designed.

If cost were no object, I would contact Matt at cNw and have a discussion with him. He would not advise you for his
personal profit, but rather best result for your situation. If cost were no object. There are cool things happening for
Mk3.
 

concours

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Barnett. Soft alloy host plate, easy on the hub. Bonded fibre friction material
works great.
Cost is not a consideration. Barnett
 

Fast Eddie

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Barnet.

They are light weight, good for your long suffering mainshaft and gearbox.

They work brilliantly. No slip, no fuss.

Some get a small ‘chirping’ noise when pulling away (when running dry), some don’t.
 
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Either Surflex of Barnett.

My original sintered bronze always used to start slipping after a few hundred miles, but that was before I fitted a DynoDave clutch push rod seal.

I had no slipping issues with the Surflex but eventually after about 25,000 miles the teeth wore to a point.

I now have Barnett plates I, and although I'm happy with the way they work I think that the teeth that engage with the clutch centre may have started to wear after a relatively low mileage, but can't confirm yet as I found some alloy paste in the primary c.c. oil twice when renewing it. Time (and miles) will tell.
 
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I fitted a set of RGM bronze hi torque plates, They were 3.6mm thick sintered bronze driven plates that filled the basket perfectly and with one finger operation its a joy to use.

ELLIS
 

p400

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After all parts removed , the 1975 Canadian Mk3 clutch hub was found to be in bad shape.


20200806_174920.jpg
 

p400

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Using MAPP gas, i had to get the engine primary sprocket very hot to get it pulled off.
So i have figured the engine crank seal is shot and needs replace.

20200803_small.jpg
 

p400

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I drilled a 3/64 hole at about the 3 o'clock position into the 1975 Mk3 crank seal, screwed in a long hex head screw, clamped on a small pair of needle nose vise grips, and held a slide hammer on the vise grips, pulled it right out,

of course the sprocket key and wire clip retaining the crank seal had been removed.
 
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lazyeye6

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So..... your parts list so far include a new clutch hub (preferably from cNw), a new clutch circlip and a new crank seal.
Oh! and a Dyno Dave clutch rod seal. Clean your clutch plates and reassemble, using ATF type F in the primary with
5 oz. Report back.
 
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After all parts removed , the 1975 Canadian Mk3 clutch hub was found to be in bad shape.
mind offering what the type and /or /brand of plates were in there? approx mileage?
thanks
Wondering why the wear depressions are rounded? and why not equal for all the plates across that face?
 

p400

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Purchased an extended 1½ " impact socket ($40) to allow easy sprocket nut (LH) remove and install.
New socket works very well.

New primary sprocket, new rear sprocket, new chain.
pulled gearbox sprocket seal and spacer, replaced with new.

Now waiting for new clutch hub and bearing.

Existing clutch plates are sintered OEM that appear with little wear.
Clutch stack height 1.050"
There was a clutch rod o-ring seal installed, planning to reinstall.


Resized_20200806_163848.jpeg
 
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L.A.B.

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Wondering why the wear depressions are rounded? and why not equal for all the plates across that face?
Seems normal for a bronze plate clutch with the deepest notching at the second and third inserted friction plate positions with less notching at fourth and practically none at the first and fifth.

 

p400

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Replaced the two seals in the primary rear.
Small shift shaft, gearbox shaft.
Cleaned up the primary/engine gasket surface.



20200806_PrimaryInnerSeals.jpg


I hear Hylomar AF is the new Go to sealant for gasket surfaces, maybe even replace gaskets.

HylomarAF.jpg
 
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maylar

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Great pics, thanks. I've never seen a MKIII apart before.
 

p400

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This 1975 Mk3 has 12k miles , i bought it with 8k.
Never has been easy to get neutral light on the road.
Clutch has been grabby, when pulled to the handlebar the clutch reengages in 1/2 ".



20200807_11916miles.jpg
 
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