Just removed my FD to grease the splines and found oil. Pretty sure its the FD input seal and not coming from the GB output seal. The FD has not been overfilled.
Any consideration when replacing this?
Is there a generic seal I could find locally or is this an oem part?
Cheers

Its a 35 x 47 x 7mm so I don't think you would have a problem getting one.
 Just fill the whole swinging arm with oil and you wont need to lube the spline. I have never been too concerned if they leak a bit but if it is getting on the rubber then it needs attention.

Thanks Rick. Ordered from munich m/c anyway. will be here monday. I put it back together with a good lick of moly till then.
Is there a knack in getting the threaded collar out?

Heat and the correct socket it will have red loctite on it. They can be a real bugger to get out sometimes but the heat usually does the trick.

Hi Capt'n,
If you need to lock the bevel drive, here's the simple tool I made to do the job.

https://www.k100-forum.com/f20-special-tools-and-jigs

Cheers,
Paul

Just me but I would get the parts and have an experienced indy wrench do it.

Could be a good idea Duck. If I can't find anyone I'll attempt it myself.
What are the difficulties once the nut and collar are off??
Cheers

take careful note of any shims etc captain


my first final drive suffered from a spacer from the pinion bearing to the pinion drive gear ...letting it move forward off the crown gear under load by more than a couple of mm's  

good luck

Kaptain Holister wrote:Could be a good idea Duck. If I can't find anyone I'll attempt it myself.
What are the difficulties once the nut and collar are off??
Cheers

If you know how to set up a spiral cut gear set then it's not difficult, If you don't know then dont touch.

Honestly - what Rick says. I do Guzzi bevel drives but usually set aside at least two hours per drive (never done a K-drive yet). If I'm very lucky I'll get the preload and backlash right within thirty minutes, otherwise... I hope someone in the house is good at supplying cups of tea and shedloads of patience. Plus multiple sets of gaskets, shims and spacers. Don't think that what comes out must go in and produce the same clearances as just changing a gasket can throw off preload and/or backlash.

I'm not a machinist but I understand what a spiral gear is and how helical teeth work.
I realise the shimming is important so as to get the pinion in the correct position to the spiral gear for proper contact otherwise you get sliding between the teeth surfaces. I'm geussing the threaded ring may play a part in that to achieve the correct preload and 'backlash'.

The shims are behind the bearing and I'm not removing the bearing, just the seal. From what I can see from the drawings, I should be able to remove the seal without upsetting the bevel/spiral gear relationship as long as I leave the bearing and shims undisturbed. Is this correct ??

As far as I can see, yes.

So providing I can get the nut and threaded ring off, I'll give it a go.

• I think I'll get hold of a dial mic and measure the backlash before and after.
  
• Is there any knack in actually getting the seal out and back in. I guess I'll need to check for wear on the shaft (That may be difficult if its not coming out).
  
• I've got a few other things to do before the Snowy run next week like the timing chain so I'll do it week after if I don't get the time. Anyone see a problem with that strategy? Its only a small leak and its not leaking out onto the wheel at all.
  

Cheers

My K100 leaked for years, there was always a teaspoon of oil in there each time I lubes the splines and that was each tyre change. Each major service I did the oil in the drive and it looked like it was full. Unless it is leaking out the joint and leaving a puddle I really wouldn't be concerned. Most Ks I have done a lube on have a tiny bit of oil in there.

Thanks for your advice Rick. It hasn't been leaking out the joint but when I opened it up the other day there was about 50ml in there which had washed pretty much all the moly off the splines. I swapped that FD in there 9 months ago and its not been checked since.
I'll check it again after the Snowy run and see whats happening but I may leave as is. I'm looking for a paralever for the old girl so this FD is going anyway sometime soon.
Cheers

Kaptain, just thinking out loud here ......... for peace of mind re oil leaking out of the joint onto the tyre would it be helpful to cut a thin paper gasket and fit that between the final drive and swingarm. I don't imagine having a thin gasket in there would cause any issues with the drive given the length of spline contact.

Cheers

Keeping my eye on it Gaz. Will be carrying som RTV on the Snowy trip just in case, but you're right, probably a good idea to put a thin gasket in there anyway.

the only real issue is that it might wash off the good spline lube grease ,,,but of little consequence if your onto it

the seal area around the joint to the swing arm doesnt seem to leak too much with that sort of fluid levels getting out of the pinion seal

just a thought

charlie99 wrote:the only real issue is that it might wash off the good spline lube grease ,,,but of little consequence if your onto it

the seal area around the joint to the swing arm doesnt seem to leak too much with that sort of fluid levels getting out of the pinion seal

just a thought

Shouldn't be a short-term problem Charlie. Going back to Guzzis (again!), the gearbox output shaft seal frequently leaks. No-one with any sense can be bothered to change it until it turns into a flood because the EP90 does a good job of lubricating and protecting the UJ and the top set of splines on the driveshaft. I doubt Nigel's going to have a problem for many K's of K's.

The gear oil is what is put in the swingarm of the R series and the splines last very well on them. The problem didn't really show up till the bricks wer about 2 years old or more depending on miles.