MKii Clutch Sticking

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Tornado

Tornado

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Clutch seems to be failing the disengage when I pull in the lever...seems to stay on for 1-3 seconds then releases fully from the tranny gears. I've tried making pushrod adjustment as described on other threads. I'm at 1/2 turn out from point where the adjuster nut seems to begin applying pressure. The clutch lever has good 3-5 mm of free play at handlebar. Was running 20w50 in primary for first 1000 miles since I've had bike 8 months) and just changed to ATF-F. Problem existed prior to that change.
What's next to try? Pulling the stack apart to clean/inspect?
Thx.
 
pull it apart and have a look see. my guess is a notched hub or gear box oil migrating into the clutch. what clutch plates are you running? if the bronze they need to go away as the gearbox oil makes them drag and slip along wearing the center hub
 
As far as I know, plates are originals, I have not taken it apart. How do i determine what they are once apart?
 
If you find the problem is the clutch centre being notched, I have tested the new ones from CNW in both my road bike and race bike, they are a no brainer, notch proof!!!
Regards Mike
 
the original plates are a heavy bronze, the most common replacements are barnett and they have an aluminum center.

Tornado said:
As far as I know, plates are originals, I have not taken it apart. How do i determine what they are once apart?
Click to expand...
 
There is nothing wrong with the stock bronze plates after 43 years I am still running my orginal plates with over 160k on them, I have done lots of burn outs in my younger days, had slipping clutch in the early days but after not using motor oil in the primary no more slipping, but of course you have to pull them out yearly for maintenance for cleaning etc, I have run them dry with belt drive but now gone back to chain primary, have only replaced the clutch centre in the last 5 years for the first time and replaced the pressure plate a few years before that, my clutch has always been light and my gears change with a light click.
I only fill my primary with 7 fl oz of tranny type F oil, never over fill my gearbox and have never had gearbox oil migrate down the clutch shaft but I do put grease on my clutch rod and I have never had to restact the plates they are still all orginal bronze and steel plates.
The secret to long life of my clutch is do the maintenance when needed, don't over fill primary or gearbox and my gearbox was only rebuilt once back in 1979 when the lay shaft bearing blew.
So for the OP just pull your clutch apart and give it a good clean look for wear on your clutch centre, make sure your pressure plate is good and adjust the right amount for your cable and put a dab of grease on the lever pivot and adjuster and make sure your cable runs freely without any kinks in it, should be a very light feel on the lever.
Good luck with it.

Ashley
 
ashman said:
There is nothing wrong with the stock bronze plates after 43 years I am still running my orginal plates with over 160k on them, I have done lots of burn outs in my younger days, had slipping clutch in the early days but after not using motor oil in the primary no more slipping, but of course you have to pull them out yearly for maintenance for cleaning etc, I have run them dry with belt drive but now gone back to chain primary, have only replaced the clutch centre in the last 5 years for the first time and replaced the pressure plate a few years before that, my clutch has always been light and my gears change with a light click.
I only fill my primary with 7 fl oz of tranny type F oil, never over fill my gearbox and have never had gearbox oil migrate down the clutch shaft but I do put grease on my clutch rod and I have never had to restact the plates they are still all orginal bronze and steel plates.
The secret to long life of my clutch is do the maintenance when needed, don't over fill primary or gearbox and my gearbox was only rebuilt once back in 1979 when the lay shaft bearing blew.
So for the OP just pull your clutch apart and give it a good clean look for wear on your clutch centre, make sure your pressure plate is good and adjust the right amount for your cable and put a dab of grease on the lever pivot and adjuster and make sure your cable runs freely without any kinks in it, should be a very light feel on the lever.
Good luck with it.

Ashley
Click to expand...
Ashman, very impressive service life from your clutch.
Can you describe your need to replace the pressure plate?
Was it heat warped or maybe to get a perfect stack height?
 
With these above replies, I'm hopeful a good clean up may resolve the issue. Bike only has 10k miles on the presumably original Smiths clock. Not expecting to see much wear.

Does brake cleaner spray and wipe down work well for the plates? Have heard gasoline can be used but would rather not use it...messy, smelly and my 2 gallon HiRider tank needs every drop!

Also read up on a pushrod o-ring seal to prevent gearbox oil reaching plates. Might go that route if issue returns in short order.
 
Im with Ashley on this one, I run the original bronze plates (dry) in both my road and race bike and dont have an issue with either now.
Initially I had a lot of slippage in the race bike , it was due to a bad stack height and the wrong thickness pressure plate .
Now all resolved.
I use an extra steel plate in the back of the road bike clutch, this is just to soften the lever pull and it doesnt slip under load.
Not so in the race bike so I go with a harsher lever pull.
Regards Mike
 
Bob Z. said:
Ashman, very impressive service life from your clutch.
Can you describe your need to replace the pressure plate?
Was it heat warped or maybe to get a perfect stack height?
Click to expand...

For some reason the pressure plate sort of went flat and wasn't holding the plates like it should have I was lucky I had a spare clutch when I first converted my Norton to the Featherbed frame I miss placed my orginal clutch so I brought another one that had fibra plates , but after a few months I found the container that had my orginal plates in it, I wasn't happy with the fibra plates as it had one miss match plate in it.
As for cleaning the plates I just put them in a container of kero let sit for awhile then give them a good scrab, blow dry with compress air and sometimes a light rub with sandpaper.
No need for pushrod O ring seal, just don't over fill your gearbox, I measure my amount of oil in a measure cup and put the right amount the bible says to use (workshop manual) and put grease on the clutch rod, I found out a long time ago using the level cube in the gearbox to for filling the oil was putting to much oil in the gearbox, the measure cup gets it right eveytime.

Ashley
 
Most common problem is oil on the plates , any kind of solvent will do the trick .
I occasionally give mine a go over with the wire wheel .
Never had a problem with the norton clutch .
 
Looks like problem now solved. I pulled the OEM brass plates and cleaned up with oven cleaner and followed with lacquer thinner...as per advice from a local Norton friend. Plates had fair amount of waxy oil scorched patches...which cleaned off with a rag. Worked a treat. Plates were in great shape according to my friend.
After button up, went for test ride and had zero clutch sticks...previous ride it occurred 8/10 shifts, and 4th to 3rd typically the shifter lever would not move while clutch held in...for 1-3 seconds unless I also blipped throttle.
Very happy.
 
Good to hear now just make sure you do the plates as part of your routine maintenance.

Ashley
 
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