C: Clutch Multi-Plate Clutches

[oexing]

Yes, that is what I´d do, get some sizes of thin cross section o-rings for trial fit. So one of them will just seal in the radius gap of the ball bearing inner race and press lightly on the PD21 spacer. The Spares Co cannot possibly supply these as I believe there will be variations in radii on inner races and PD21 chamfering as well - no ?
In this place the o-ring is just a static seal , not critical.

Vic

 

[highbury731]

I see that Seals R Us offer 25mm x 1mm O rings. A standard PD21 with small chamfer ground into the gearbox side as necessary might be the go, then

 

[timetraveller]

Personally, I would go for a larger section if you were going to place it at the end of the tube of the shoe carrier. I 've just looked up on Simply bearings and they list a pack of two 25 mm ID by 2 m section and then 2.4, 2. 5- and 3.0-mm section. I did try to find imperial sizes on several sizes but nothing in the range which might be useful.

 

[Robert Watson]

As has been pointed out, an o ring between the PD21 and inner race of the bearing is not functioning as a normal or ring, when the whole plot is together the PD 21 and the inner race are held tightly together and there is no axial movement between them. The o ring is just a packing seal but way more convenient to install than trying to get just the correct amount of (insert the name of your favourite sealant here) in between the two.

 

[erik]

I like to do long distance touring and therefore I like to keep things simple.I have the Neal Videan wet clutch fitted with smooth operation and low force on the lever.Because the clutch is wet there is no problem with oil contamination. I use the Harley Davidson primary drive oil . Regards Erik

 

[highbury731]

Having taken another look at my engine, I realise that I have already fitted PD21, and it does not want to come out, due to a close fitting G24 seal. It was a while ago that I last worked on this area.....

I came up with another idea. The C18/1 seal is completely ineffective, as the rubber touches neither the spline area nor the threaded shaft. It has no chance at all of doing ANYTHING. A fellow Vincent owner said that many people fit a Series D o-ring along with it - but that has no real chance of doing any good either.

What about a Series D o-ring on the shaft to seal against the end of the shouldered spline area, and make a stepped disc to press on it, in place of C18/1?

I measure the spline area of the shaft as 1.52" long, and the depth of my shoe carrier 1.790". That makes the overall thickness of the shoulder 0.270" minus depth of the recess for the C18/1, the thickness of the O-ring (3/32") and minus 5 thou. That means a minor turning job, and no hardening required.

That comes to 0.270 - 0.075" - 0.094" - 0.005 = 0.096"

Come to think about it, didn't Trevor Southwell suggest such a seal arrangement?

 

[timetraveller]

In my opinion any sealing arrangement at the outer end of the shoe carrier will not be as good as one at the inner end. My system, or the one suggested by John Webber at the inner end will work. Truly my clutch gets dusty, not oily. I realise that it might seem worrying to set about changing something mechanical on a bike but trying to recall what I did over sixty years ago is not easy. I was not long out of school, had no mechanical background or access, or the skills to use, machine tools. I know that I veed out the inner end of the shoe carrier tube by hand and my guess is that I would have used a small rotary grindstone in an electric drill controlled entirely by hand. It worked for years and later I did another bike by using a valve seat grindstone in a pillar drill. I realise that both approaches will seem like barbarity to a proper engineer, but they worked, and you could hardly do worse. You do not have to invent anything. Preferably find a local friend who has machine tool competence or ask around the local Vincent owners. Someone will know someone etc who can help with this simple job. Remember, if I could do it in my late teens then so could anyone.