Gearbox output seal weeping

[Bendy toy]

I've got my swing arm off and noticed a slight weep of oil at the gearbox output shaft. Oil level is per the book.

Question 1
Is a weep of less than 1ml normal or should it be totally dry?

Question 2
The Haynes book uses two self tapping screws to pull out the old seal. Is this correct?

 

[Deleted account 190920001]

As per any seal it should be totally dry and although your is a minor leak your in there anyway and it isn't going to get any better with time.

Yes you can is self tapers to pull a seal just don't go driving them into the bearing behind.

 

[Bendy toy]

Thanks I thought as much. It's now got me concerned about the input shaft.

 

[Bendy toy]

Ordered input and output seals. Taking the box off tomorrow.

 

[Spout]

Check the gearbox breather isn't blocked.

I've twice had gearbox leakage - both times breather wasn't working (once combined with a slight overfill).

I regularly clear breather now - no more seeps.

 

[Bendy toy]

Gearbox is now off. What a struggle - the top LHS dowel tube would not let go. No corrosion thankfully just very tight.
The breather is also fine. I've just got back from lunch to se a lubricated garage floor. I'd sat the 'box on its side and oil has dribbled out of the breather.
The input seal is dry, input shaft splines look good and clutch plate gap is 5.3mm. Minimum is 4.4mm so I'm not going to the expense of a new clutch just yet.

 

[Pukmeister]

If I had mine stripped that far, I'd dismantle the clutch and inspect/measure it properly plus lubricate the clutch splines with a dry film lubricant. An ideal opportunity whilst in pieces to do it right.

It would cost you a new set of clutch mounting bolts but thats better than having to do the job again in future.

 

[Bendy toy]

That makes sense when everything is covered as in a car. The 1200 clutch is not misbehaving and the gap between the pressure plates - friction plate thickness - is easy to measure.
Brand new clutch plates are 7mm. Service limit is 4.4. Mine is 5.7. It's done 50000 so I reckon another 30k is likely.

 

[Bendy toy]

Reading that back, my reply sound sharp. Not meant to be - sorry.

 

[Bendy toy]

The gearbox and starter are now back on the engine.
I used Copaslip on the input splines. It's just a smear don't want the clutch lubricated.
The shaft splines were dry and looked like they never had any lube at the factory. But no signs of wear.

The output shaft seal is replaced. The Haynes method works fine.

The gearbox mounting bolts were corroded so I've used Copaslip over the whole length. That demanded manual tightening because I don't have the % reduction figures to risk the torque wrench.

The top LHS gearbox bolt dowel was well stuck and a real struggle to shift.
I've tapped it through M10 so next time it can be jacked out with a long threaded bolt.

 

[Steptoe]

The gearbox and starter are now back on the engine.
I used Copaslip on the input splines. It's just a smear don't want the clutch lubricated.
.

A BIG no no. Copaslip is an anti seize paste, not a spline lubricant .

 

[Bendy toy]

Booger but thanks for the heads-up. It will have to come apart again.

I reasoned that as the clutch is not sliding on the shaft, the last thing I want is any sort of pick-up between the parts. What do you suggest is best to use on the splines?

 

[Steptoe]

I reasoned that as the clutch is not sliding on the shaft, the last thing I want is any sort of pick-up between the parts. What do you suggest is best to use on the splines?

The clutch friction plate does slide on the shaft.

Optimol paste for clutch splines.

 

[SteveM]

Optimol paste for clutch splines.

Is that the same stuff you use on the FD splines as well?

 

[Bendy toy]

The clutch friction plate does slide on the shaft.

Optimol paste for clutch splines.

Thanks I'll get some.

 

[birdseye]

Booger but thanks for the heads-up. It will have to come apart again.

I reasoned that as the clutch is not sliding on the shaft, the last thing I want is any sort of pick-up between the parts. What do you suggest is best to use on the splines?

Best thing for the splines is the 80% moly disulphide grease. Thats what Honda recommend and use ion their drive shaft splines to prevent fretting

 

[MattW]

As Neil says definitely not Coppaslip it's not a lubricant (despite many people thinking it's some sort of wonder grease which they plaster all over stuff) . Optimol is best but I had trouble getting it so I used Honda moly 80 paste. Use the same stuff on FD splines etc. Clean all the Coppaslip off with a solvent and be sparing with the lubricant you use.

If I'd gone to the trouble of splitting the bike with the clutch more than half worn, I'd have changed the clutch (wear rates are usually non-linear - the last bit of plate wears faster than the first). But, your call...

 

[Pukmeister]

Ideally you want a dry film lubricant, we used to use some Rocol stuff for stainless-to-stainless fitting on gas turbines to prevent galling. It paints on then dries to a black thin film capable of withstanding 30,000 psi. We used to paint on two coats thinly then assemble once dry.


EDIT: Just found a tin of the stuff on ebay, only £141 for 750 grammes Wish I had 'acquired' a tin from work when I had the chance !

Some Molyslip AS60 would probably be just as good, the molybdenum disulphide layer formed prevents wear to sliding components.

 

[MattW]

Ideally you want a dry film lubricant, we used to use some Rocol stuff for stainless-to-stainless fitting on gas turbines to prevent galling. It paints on then dries to a black thin film capable of withstanding 30,000 psi. We used to paint on two coats thinly then assemble once dry.

EDIT: Just found a tin of the stuff on ebay, only £141 for 500ml Wish I had 'acquired' a tin from work when I had the chance !

I used similar on my input splines - a spray on dry film moly product in a solvent carrier that evaporates. I have a can from doing gun slides back in the day (remember it being horribly expensive). You spray it on, let the solvent evaporate and polish it with a rag, ideally repeating once more without polishing the final coat. It gets into the pores and grain boundaries of the steel and leaves it an even gray colour.

I did this to my splines and then backed it up with Honda Moly paste as a belt and braces.

 

[Pukmeister]

..... let the solvent evaporate and polish it with a rag, ideally repeating once more without polishing the final coat. It gets into the pores and grain boundaries of the steel and leaves it an even gray colour.

I did this to my splines and then backed it up with Honda Moly paste as a belt and braces.

A burnishing process as we called it. Your input splines will probably outlive the rest of the bike.

It's all to do with Molybdenum and sulphur forming layers (hence Molybdenum DiSulphide having two sulphur and one molybdenum), a thousandth of an inch coating contains tens of thousands of layers of molybdenum and sulphur molecules all sliding across each other hence preventing wear between sliding components. Copper grease is just solute copper particles dissolved in a grease binder/carrier.