New clutch plates for a Mk3

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p400 said:
Replaced the two seals in the primary rear.
Small shift shaft, gearbox shaft.
Cleaned up the primary/engine gasket surface.
Click to expand...

I would put a smear of RTV (or your choice of sealant) on the OD of the alternator wire seal and then on the alternator wire just as you draw it into place. I put a new one of those on, and it leaked from there from the get go. Very irritating.
 
Good idea to seal the wire, maybe add sealant at the thru bolt as well.

I think my biggest leak from this primary was the shift lever shaft on the outer cover.


New clutch plates for a Mk3
 
Now I want to assemble the Mk3 clutch basket/hub/bearing assembly.
I have a shop press, but wonder if heat/cold might be of use here.

The bearing needs to go into the basket first followed by circlip.

basket is oem, bearing new Andover, clutch hub new RGM.
Do I need to check any dimensions before this goes together?

Lower the bearing temp using upside down can of computer duster?
Heat the steel basket with MAPP?


20200808_ClutchHubBrgFit.jpg
ComputerDusterFreeze1.jpg
 
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Cold is Ok- all components are steel. done it many times
a little oil is good
correct - push in portugal bearing on OD into basket
circlip it
then push clutch center while supporting bearing on inner race
circlip it
you probably knew that...
 
Hi P400,
I have a MKIII. I replaced the clutch center and a couple of the sintered plates with fresh ones and put a Venhill teflon cable on the whole works , and the clutch is easy to pull and smooth. Went with a new 18 tooth sprag. So far so good. One innovation was getting rid of the Boyer , which kept kicking back during starting and tripping the backfire clutch. Put in a Trispark and got a 95% reduction in occasions of tripping the backfire clutch. Once in a while, it will kick back a little bit in a stall. But nothing like it was with the Boyer.
Sincerely,
Kara
 
p400 said:
I think my biggest leak from this primary was the shift lever shaft on the outer cover.
Click to expand...
Did you check for a crack? A lot of MKIII will crack there if the bike is ever rolled/tipped onto the lever. The outer case is very tender...The bush looses support.
 
I ckd all shift shaft area for cracks, however i had looked all over prior as well.
Never hurts to look in magnification.

New clutch plates for a Mk3
New clutch plates for a Mk3
 
I did assemble clutch basket/bearing/hub.
I used shop press, room temp for all pieces.
Seemed reasonable and easy. Thanks
20200809_BaskeAssm2.jpg
20200809_BaskeAssm1.jpg
 
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I have installed a new circlip on the shift shaft.
I noticed it was curved ,not sure why, it was installed curve up which made it slightly difficult.
Now the shift shaft is being pulled tight to the outside, no wobble as the gear is tight against the machined surface internally.
Now difficult to turn by hand.

Anyone else see this same circlip install?

20200809_ShiftShaftCirclip1.jpg
 
I thought it was support against antivibe damage.
In a similar fashion the mass of rearset shift lever & shift rod situated on the stable frame and the iso mounted gearbox jumping around can cause very fast wear of the gearbox shifter bush. I was shocked to see the super sloppy gearbox lever on a guys 850 with dunstall rearsets...the MKIII has even less support.
 
I think it’s curved to take up the free play. Also pretty sure that’s how I installed mine. My original fell off while I was riding so I don’t know exactly how it was. FWIW I think the original seal was in inches and was a grease seal and did not have a spring inside. The replacement was a metric oil seal that did not want to stay in place. I wound up using Permatex Aviation sealer to “glue“ it in place.
 
L.A.B. said:
Yes, so I'd say the washer was most likely the cause of the problem (too wide) and not the curved circlip.
Click to expand...

LAB, I ckd thickness of old washer = 0.071"
thickness of new Andover washer= 0.072"

Old shift shaft outer washer was quite marred up from something and this something was the ears of the circlip digging into the washer surface at every install.
And now my new washer is quite marred up from several installs, not complaining simply info about this "curved" circlip.

The question i now have is why had the previous washer been on/off several times?
Is this shift shaft seal leak a continuous issue with a Mk3?

20200810_Circlip1.jpg
 
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p400 said:
LAB, I ckd thickness of old washer = 0.071"
thickness of new Andover washer= 0.072"
Click to expand...

0.064" here.
No scuffs or gouges on the washer just a dull ring caused by the washer rotating.
 
Original curved circlip and washer on mine seem fine. I've had this apart last year to change out the seal , it was a bit firmer feeling than the new softer one I installed. Yet the seal still lets oil by in a misty deposit form on the outside of the cover. Not a drip leak. I can live with it. I changed the bushing too at that time.
 
In checking the outer primary Mk3 cover, I found the area around the drain plug has been polished to a rounded surface.
Not allowing a good seal surface for the OEM Andover red fiber washer.
is there a better Mk3 primary drain bolt seal to install?


20200811_PrimaryDrain.jpg
 
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