MKIII allowable clutch drum wobble question

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AntrimMan

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Just how much wobble is allowable measured at the pressure plate end for reference?

My clutch has been dragging so I thought I would have a look see.
I collected all the chaincase lubricant, every last drop, and I almost filled two little cans of 7oz each. The first can is brimming, the second is in the photo. Too much I'd say.
It smells of gasoline too, strange, maybe the PO washed it out, the stink does stay around forever.
This oil still feels like oil between the fingers. The engine oil does not stink like gasoline. The gearbox oil does not either.

MKIII allowable clutch drum wobble question


I was hoping to see the original sintered bronze plates but disappointment has set in.
I had put Barnett plates in a wet clutch Honda once and would not do it again because overnight the plates would stick together.
Will these aftermarket plates do the same in the Norton? answers anyone please?

MKIII allowable clutch drum wobble question


So, just how much wobble is allowable measured at the pressure plate end for reference with the plates removed?
I suppose the lock washer is there to fold around the nut, the last person in there didn't think so. I took these early this am and didn't notice the lockwasher until I was looking at the photo's here at work. I miss the obvious all too often and so did the last person in there too.

MKIII allowable clutch drum wobble question


I imagine some wobble is inherent in the ball bearing with the drum being supported at only one end, no?
And there must be some stabilizing or centralizing effect from the tapers on the splines too?, no?
Any idea's?
 
Barnett plates work a treat dry or in ATF and Barnett says to wet new plates with ATF then wipe off a bit to prevent chatter on initial bedding in. i love my Barrnetts easy no stick function and release.

There really should be No Wobble to detect in fully fettered tranny. Wobble mostly comes from the worn sleeve bushes and should be replaced with 3, by using an old one as middle spacer to keep the end ones aprat to best bear the shaft loads.
Hub bearing can go bad too of course. OIl can not get into these sleeve bushes once running in lower gears so I've tried to help them by spiral oil grooves, but just short of end of the DS bush to try to sitffle the leak into primary via clutch basket.

Can't understand how gas might get into primary so may learn from you if you figure it out. Chain primary can stand a good bit of wobble but not belts.
 
wobble is normal on mk3. at least that's what people said when I asked building mine. There are other threads that say it's normal too if you use the advanced search.
 
Wobble is probably normal, but it is not desirable. When I installed my primary belt kit a few years back (and I highly recommend you eventually do so) I observed that spinning the clutch center with the clutch plates removed caused the clutch basket to wobble. The only thing it could have been was that the main shaft was not straight. So after pulling the main shaft out and checking it in "V" blocks sure enough it was curved a few thousandths of an inch. Using my hydraulic press and some hardwood blocks (and quite a bit of patience) I was able to get it straight (no deflection on the dial indicator). Once reinstalled and running the clutch now runs very straight and true.

GB
 
AntrimMan said:
I collected all the chaincase lubricant, every last drop, and I almost filled two little cans of 7oz each. The first can is brimming, the second is in the photo. Too much I'd say.
Click to expand...


Yes, about twice as much as should be in there (200cc/7Imp. fl. oz/6.7 US fl. oz.).


AntrimMan said:
It smells of gasoline too, strange, maybe the PO washed it out, the stink does stay around forever.
Click to expand...

Perhaps the extra quantity leaked past the crankshaft seal or along the stud threads?



AntrimMan said:
I imagine some wobble is inherent in the ball bearing with the drum being supported at only one end, no?
Click to expand...

I suggest you clean the plates and completely re-assemble the clutch, and then check for wobble?
 
Weebles wobble but they don't fall down so methinks yer primary crank seal has failed. Pull everything and replace it.Use a new cltch circlip. Check the clutch center for notching. Use less and lighter oil in primary or as suggested go to dry belt drive. Oh yes, those lockwasher tangs are to peen over the nut to prevent catastrophic backoff of nut , failure always proportional to distance driven from workshop or tools to remedy . Use oil resistant gloves as your posted photos show carcinogenic gew all over. Good luck ,Pedro el Pescador.
 
Torontonian said:
Use less and lighter oil in primary
Click to expand...

As it's a Mk3, the quantity of primary oil should be maintained in order to keep the hydraulic primary chain tensioner functioning correctly.
From personal experience, I wouldn't recommend using lighter oil in a Mk3 chaincase. 20w/50 works fine.
 
Yes L.A.B. , forgot it was a Mk111 so use the correct amount of oil and grade for both tensioners to do their thing. The front sprocket puller has longer draw bolts if memory serves and the questionable seal is held in by a circlip.
 
All the seals are sealing just fine.
I believe the gasoline smell is a symptom of the PO washing the clutch elements.

I've given this whole topic some more thought, since I'm in there, and have concluded:
A)
The friction material should just as well be made for a wet clutch and the oil level compensated.
These will never-ever be a dry clutch after the engine is started for the first time subsequent to clutch installation.
If you look at the photo there are 6 through holes radially arranged in the clutch sprocket.
They will let as much oil in as out. When the engine stops the residual oil on the chain will enter the clutch pack through these holes.
It has nowhere else to go but into the interior of the sprocket.
The sectioned model shows where the holes penetrate the interior, right onto the inner most friction disc.
Maybe I just don't interpret "dry clutch" correctly. Perhaps it should be phrased "self oiling clutch" instead.
Oh well.

MKIII allowable clutch drum wobble question


MKIII allowable clutch drum wobble question


B)
This may mean that any of the gearbox oil that may happen to migrate through the mainshaft is of little consequence.
Although it will be centrifugally spread toward and along the diaphram it would have a harder time getting to the pack than the chain oil and there would be much less of it to begin with.

C)
I know it's the popular thing to do, but...
Any sealing of the clutch actuating pushrod effectively closes the only atmospheric vent for the primary chaincase.
Not the end of the world I agree, but keep in mind another popular alteration to pre MKIII gearbox outer covers is the addition of what? an atmospheric vent indeed.

D)
A thinwalled light weight inverted cone fitted to the inside of the clutch adjusting boss and allowed to centrifugally spew it's contents radially through a few drilled holes would work as well as anything else and not block the vent.
Norton could've, should've, would've made this cone shape integral to the inside the adjusting boss if it had been necessary. I'm convinced of it.

Thoughts, comments, convincing otherwise is humbly invited.
All the best.
 
AntrimMan said:
All the seals are sealing just fine.
I believe the gasoline smell is a symptom of the PO washing the clutch elements.

I've given this whole topic some more thought, since I'm in there, and have concluded:
A)
When the engine stops the residual oil on the chain will enter the clutch pack through these holes.
It has nowhere else to go but into the interior of the sprocket.
Maybe I just don't interpret "dry clutch" correctly. Perhaps it should be phrased "self oiling clutch" instead.
Oh well.
Click to expand...

Amount of oil that can enter through those holes when the engine stops is probably negligible.

"Dry clutch" refers to the situation once a belt-drive is installed.

AntrimMan said:
C)
I know it's the popular thing to do, but...
Any sealing of the clutch actuating pushrod effectively closes the only atmospheric vent for the primary chaincase.
Not the end of the world I agree, but keep in mind another popular alteration to pre MKIII gearbox outer covers is the addition of what? an atmospheric vent indeed.
Click to expand...

THe difference between venting the gearbox vs. the primary might the volume of air in the primary.

AntrimMan said:
D)
A thinwalled light weight inverted cone fitted to the inside of the clutch adjusting boss and allowed to centrifugally spew it's contents radially through a few drilled holes would work as well as anything else and not block the vent.
Norton could've, should've, would've made this cone shape integral to the inside the adjusting boss if it had been necessary. I'm convinced of it.

Thoughts, comments, convincing otherwise is humbly invited.
All the best.
Click to expand...

Not sure what you mean about the "vent".
 
that lockwasher is no good, they are soft so they compress and allow the nut to loosen even when the tabs are bent and that can lead to excessive wobble, had this happen on my MK II. Learned here (from Comnoz IIRC) that that was the problem and that bellville washers work much better and ordered a dozen recently as that was the minimum from the supplier. If you need one I'll mail one at cost + postage, about $4

MKIII allowable clutch drum wobble question
 
AntrimMan wrote;
This may mean that any of the gearbox oil that may happen to migrate through the mainshaft is of little consequence.
Click to expand...
I run my MK3 (with oil in the primary) and have fitted five years ago the Dave Comeau pushrod oil seal onto the end of the gearbox mainshaft. I have had the clutch apart a few times over the yearsto deal with other issues and I find only the slightest bit of primary oil on the plates and no gearbox oil, and I never have clutch slip, and I run surflex plates. I personally think that this mod is one of the best ones to do to your Commando. Gearbox oil is much more viscous, and on my previous Commando, when I never had this seal on, I was always having clutch slip, and that was after putting the ball bearing mod in the pushrod mechanism to stop the "pumping action" that the rod flexing allegedly created.

I do have a set of phosphur bronze plates somewhere if you really want some.

The other thing to look at regarding the clutch wobble is in my opinion, that the bearing in the clutch centre is of the "one dot" or as it is now known "C2" specification. These bearings are more stable than the standard bearing and resist wobble, but that wont mean that you wont have any :lol: :lol: This spec is the standard spec from Norton.

I wouldn't worry about the primary not venting, but if it concerns you, get a VENT PIPE, Part Number: 065199 Price, £4.25 from A/N.
 
AntrimMan said:
All the seals are sealing just fine.
I believe the gasoline smell is a symptom of the PO washing the clutch elements.

I've given this whole topic some more thought, since I'm in there, and have concluded:
A)
The friction material should just as well be made for a wet clutch and the oil level compensated.
These will never-ever be a dry clutch after the engine is started for the first time subsequent to clutch installation.
If you look at the photo there are 6 through holes radially arranged in the clutch sprocket.
They will let as much oil in as out. When the engine stops the residual oil on the chain will enter the clutch pack through these holes.
It has nowhere else to go but into the interior of the sprocket.
The sectioned model shows where the holes penetrate the interior, right onto the inner most friction disc.
Maybe I just don't interpret "dry clutch" correctly. Perhaps it should be phrased "self oiling clutch" instead.
Oh well.


B)
This may mean that any of the gearbox oil that may happen to migrate through the mainshaft is of little consequence.
Although it will be centrifugally spread toward and along the diaphram it would have a harder time getting to the pack than the chain oil and there would be much less of it to begin with.

C)
I know it's the popular thing to do, but...
Any sealing of the clutch actuating pushrod effectively closes the only atmospheric vent for the primary chaincase.
Not the end of the world I agree, but keep in mind another popular alteration to pre MKIII gearbox outer covers is the addition of what? an atmospheric vent indeed.

D)
A thinwalled light weight inverted cone fitted to the inside of the clutch adjusting boss and allowed to centrifugally spew it's contents radially through a few drilled holes would work as well as anything else and not block the vent.
Norton could've, should've, would've made this cone shape integral to the inside the adjusting boss if it had been necessary. I'm convinced of it.

Thoughts, comments, convincing otherwise is humbly invited.
All the best.
Click to expand...

FWIW
"Dry clutch" was popularized by BDM since the outsourced non norton commando design clutch friction "maths" was done without lubrication by primary oil as a consideration...though the plates are actually "soiled" by primary oil. The addition of gearbox oil to the clutch is the nail in the coffin.

The aftermarket gearbox venting mod, sometimes also popularized by some, has been proven and demonstrated at many tech sessions to be absolutely unnecessary. The gearbox absolutely can not hold any pressure without extensive engineered mods to make it hold pressure (mainly due to the clutch cable). IMO it is absolutely laughable to perpetuate this myth.

Primary venting is possibly only a problem for MKIII with a seal at the sleeve gear shaft, with the addition of a CCRS.
In practice, lack of a ccrs is a definite problem, while lack of primary venting has never seemed to come up as an issue.

AntrimMan
Even if you have no desire to join the NENO chapter of INOA, feel free to come up to hamilton ma for a 1st or 3rd saturday tech session and I could show you.

dave
3-MKIII
1-74
1-73 850
1-73 750
1-72
1-71
1-68atlas
1-65atlas
1-63atlas
1-52model 7
1-51model 7
 
AntrimMan said:
Any sealing of the clutch actuating pushrod effectively closes the only atmospheric vent for the primary chaincase.
Click to expand...

Pressure inside a Mk3 chaincase isn't a problem as far as I'm aware, however, I think the three starter motor fixing screw holes in the inner primary case are unlikely to be completely air-tight even with the screws fully tightened?
 
Gearbox breathes via the cable entry loose fit hole in top and primary out the loose felt felt seal along with tranny and primary lube. I've gotten 3 trannies to give solid stable clutch basket by renewing the sleeve bushes, hub bearing and getting straight new shafts in 2 of them. I believe the main reason for clutch wobble beside just time and wear is at least one event of too tight a chain or belt when hot on road use. I've learned not to do that no more by creeping up on tension when full hot. One of the neatest mechanical highs I've gotten is fitting a belt and running it w/o the front pulley side plate to see it staying centered on its own. If there is enough clutch wobble you can feel then they tend to walk right off or bind up on side plate and rub themselves apart at the frail edges. Its old shop gem to place a 3rd sleeve bush on shaft to keep the two new ones where they can do some good. These sleeve bushes can not get any lube in them when shafts/cogs are spinning in lower gears so I tend now to oil groove them but just short of end of the DS one [or more oil exits] and try not to spend much time in lower gears especially reving up like in 2nd to race around unless I intend to open er back up d/t clutch wobble too soon. Hardened washer out of my small round thing bin and locktite keep my nuts fixed up snug now : )

Friction surfaces are happier with Type F-Ford-Friction ATF on them, so wonder if the ES 850 could use that instead of thick gooey engine grade oil?

DynoDave gave me some of his first rod end seal, mostly d/t feeling sorry for me being a stupid newbie with extreme issues on pre-Peel Combat. Its a gem of an item and works as advertised. Still not bad idea to grease the rod to stifle oil weep and rusting.
 
hobot said:
Friction surfaces are happier with Type F-Ford-Friction ATF on them, so wonder if the ES 850 could use that instead of thick gooey engine grade oil?
Click to expand...

Well, this has certainly been discussed before (not all that long ago in fact) as the viscosity of the primary oil does affect the Mk3's hydraulic primary chain tensioner operation. I've never considered 20w/50 oil to be too thick for the clutch and 20w/50 engine oil has always performed just as well if not better than ATF (with bronze plates at least) as I had used ATF in my Mk3's chaincase before-but after changing to engine oil I wouldn't go back to using ATF or recommend it for a Mk3 primary case.
 
LAB
Might be a good experiment to test this theory...pressurize the MKIII primary with a CRS installed and see if any soapy bubbles get emitted and where?
Further results from the previous gearbox pressure test:
On a CRS equipped gearbox the 2nd largest leakage point, after the clutch cable, (not counting the normal drilled cap hole) is the mainshaft/sleeve gear bushes!!

Hobot
Remember this is a MKIII there is not a felt seal but a real seal....
 
dynodave said:
LAB
Might be a good experiment to test this theory...pressurize the MKIII primary with a CRS installed and see if any soapy bubbles get emitted and where?
Click to expand...

OK so I did just that (using a blow gun with a Triumph OIF tank mounting bolt rubber bung as the seal between the gun and the timing aperture).

The three starter mounting screw holes didn't prove to be particularly leaky (unless loosened)-however any pressure inside the case soon dropped to nothing, as air could be heard escaping from somewhere at the back of the inner chaincase, possibly through the alternator wire grommet, cross shaft seal, case steady stud hole or mainshaft seal-but I couldn't say which.
 
Oh yeah I forgot about the wire grommet vent, duh. I don't know about the 850 chain tensioner expect its fussy on oil grade, so take your testing to avoid ATF in them.

One defense Ms Peel has to delay clutch wobble is Maney's out rigger but it requires a huge hole, nay section cout on of inner cover to clear the mount so an issue to seal oil tight. I did that but don't care to do again and won't need to with dry belt.

MKIII allowable clutch drum wobble question
 
Also, the sleeve gear protrudes into the primary case, as the oil seal behind the clutch runs on the sleeve gear and not the mainshaft and there is no seal between the mainshaft and sleeve gear, so any build up of pressure inside the primary case could also get to the gearbox by passing between the mainshaft and the sleeve gear.
 
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