Clutch etc.

[Zander]

Not good this morning - another smattering of oil on the floor under the gearbox.
It looks like it's coming from the oil seal, which is bad news, as, according to the book it means engine out to fix it.  While I detest seeing oil under any of my bikes, I'm tempted to ride it for the year and deal with it later, unless, of course it gets worse as I ride it.

[Topdad]

Take no notice of that book the box comes out quite easy ,I'm doing my box now engine still happy in position , but good idea get a few miles on it good weather issss coming ..... I hope 

[JulianS]

To get at the gearbox seal you just need clutch and primary cases off.

Sometimes they dont fit too well because the outside diameter of the current production ones is slightly larger than the original. You may need to dress it to fit square against the bearing.

Oil can also seep out between the mainshaft and the bush in the sleeve gear. Worse when left on side stand. Solution is a special nut with built in seal. SRM do them. Cured my leak with one.

[Zander]

Fantastic! I was hoping it could be done without a complete strip down.
Hat tip to JulianS and TopDad, and thanks for the info re the SRM nut Which might be what I need.

[trevinoz]

If your bike is on the side stand the oil could be leaking along the main shaft through the sleeve gear.

[Zander]

98% of the time it's been on the centre stand, and it's been leaking ever since I got it.  I'm amazed there's any oil left in it!  While grovelling, trying to get my head under the gearbox, I noticed that someone has fitted the rear tyre with the directional rotation arrow facing the wrong way.  Can't see that it matters, really, as the tread is symmetrical.

[Zander]

Update:  Got back to working on the beast yesterday after a bit of a lull.  Ran the bike to test clutch setting prior to refitting the chain case etc., as I didn't want to have to do it all again.  With engine running, wheels on ground(!) gear selection was good so applied front brake and let clutch out, achieving a little rear wheel spin.  Pulled away a couple of times - all ok.
Applied sealant to chaincase and put it all back together.  Last night, took it round the block for a short test ride. Went ok apart from running a bit lumpy, but maybe because I'm not familiar with the beast, that's normal.  Rode back into garage and guess what?  When I tested the clutch, what DIDN'T I do?  I didn't try to select neutral with the engine running because I deliberately stalled it during the clutch slip test, and unfortunately it's impossible to shift the gear lever until I stop the engine!  I shall ride it  round the block a few times, but I reckon it'll all be coming apart again. Bummer!   I was contemplating drilling a hole in the casing as per that provided on other models, and making a screwed bush to provide easy clutch adjustment, but didn't do it.  How I wish I had!!!

[duTch]

 hang in there and just get on the road and road test it with all due care...

 

....98% of the time it's been on the centre stand, and it's been leaking ever since I got it.  I'm amazed there's any oil left in it!  ....

 As far as I can tell from looking in the GB inspection cover, the oil level is only about the top of the layshaft which is below the mainshaft, so on the centre-stand it shouldn't leak through the sleeve gear anyway,maybe it's over filled  ( ?) Mine leaks a few drops, but I don't care too much no puddles after work, no puddles at the pub, no puddles unless it sits for 

I was contemplating drilling a hole in the casing as per that provided on other models,

 why bother; you still need to get the lift at least vaguely equal, which can't be done effectively if it can't be seen

[Zander]

Fair point re achieving equal lift.  It's a pain having to remove the casing though as I used all my PTFE tape up fighting leaks from the screws!  When I drained the gearbox I put just under 400 cc in but couldn't get the level bolt out so I left it.  Reckon I'll have to used the percussive impact method to shift it.

[Zander]

The bike has been on the road and it runs well.  I fitted a clutch lever with a 1 1/8 pivot and it's an improvement.  After a fairly brisk 15 mile run, there was a fair bit of oil under it, so today I've bitten the bullet and got the clutch cases off so I can get at the gearbox to check the location of the leak(s).  I'm considering altering the thrust plate and push rod  to use a thrust bearing while I'm at it, and may well also see if I can fit a proper oil seal in the sliding plate.  Busy busy

[JulianS]

If you find oil leaking from the sliding plate/ clutch centre try a felt disc on back of clutch centre - fitted one ages ago and no leak in that place. Got it from SRM. Easier that fitting a seal in the sliding plate?

[Zander]

A lot easier! I'll be having a look at that, thank you.  I'm just trying to eliminate as many potential leaks before I reassemble it all, cos it's a pain having to do things more than once!

[chaterlea25]

Hi Zander,
The gearboxes can leak if the sprocket nut is not fully tightened, I have resorted to putting some sealer into the splines at times
Another source of gear oil leaking is between the casing and layshaft bush, I have found the casing holes damaged from previous owners use of the BFH

John

[Zander]

Hi John
Thanks for the tips.  As a matter of interest, although I can guess at it, what's the BFH?

[Greybeard]

Hi John
Thanks for the tips.  As a matter of interest, although I can guess at it, what's the BFH?

Big *ucking hammer? Although, *ucking big hammer would sound better to me.