Clutch basket play and ? gearbox problems on MK3.

L.A.B. said:

cash said:

In fourth the force will be mainly loaded on the layshaft bearing not the bush and give the rear brake an easier time holding. No slippage no movement.

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I cannot see that there should be any real loading on the layshaft at all if top gear is selected? As any loading goes directly from the mainshaft to the sleeve gear (via mainshaft 3rd) the layshaft is, in effect, idling when top gear is selected, top gear being 'direct drive' (1:1) as I see it the main loading will be taken by the mainshaft output bearing.

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As you say, the layshaft is merely idling when the sleeve gear is dogged to the mainshaft. I suspect that Nortons (or was it originally AMC ?) have not helped on this point by referring to the smallest gear on the layshaft as "layshaft 4th" Didn't it really ought to be called "layshaft 1st 2nd & 3rd" ? It is only in the lower three gears that it takes any driving load.

79x100 said:

As you say, the layshaft is merely idling when the sleeve gear is dogged to the mainshaft. I suspect that Nortons (or was it originally AMC ?) have not helped on this point by referring to the smallest gear on the layshaft as "layshaft 4th" Didn't it really ought to be called "layshaft 1st 2nd & 3rd" ? It is only in the lower three gears that it takes any driving load.

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Yes, the description 'layshaft 4th gear' would appear to be a bit misleading! But I don't think we can blame Norton (or AMC) for that, as other British manufacturers would seem to have used the same description.
Perhaps 'layshaft output/idler gear' would be a better name for it?

LAB and 79x100,
You are both quite correct there shouldn't be any real loading on the layshaft, just another senior moment I'm afraid.

I know how it feels Cash, comments which are lost in the haze of conversation down the pub on clubnight become preserved for posterity (possibly ?) on the internet. How many times have I thought Did I really say that ?"

At the risk of dragging this off topic, I have had a look at my "Dolls head" parts books, the AMC box being really just a simplified and, perhaps, less well engineered version of its' predecessor. The layshaft gears are described, respectively as "Low gear and kickstarter wheel", "Layshaft sliding pinion", "Layshaft free pinion" and "Layshaft pinion" so it looks as if Edgar Franks knew how to explain it.

I blame the AMC influence. As John Hudson used to say " Birmingham would never have done that. I don't know why Woolwich thought they could get away with it" ! (I really need an emoticon for a Yorkshire accent here !)

Cash said

Then turn one over and repeat. Do this with the set and try to check all the plate against each other. If you've got more than one warped plate the gap is doubled and is easily seen. Check the steel set too you never know.
I'd put my money on warped surflex plates.

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I have checked my plates, and the surflex plates are OK, but the steel ones, except one, are warped to varying levels.

So I ordered some new plain plates from BSA-REGAL which have arrived today, and on inspection I have found that they too are warped, if not as much, nearly as much as the plates I was replacing.

So my question is, how much is too much, and is it possible to grind them flat by hand. I have made a start on one plate with some wet & dry on some plate glass and you can definately see some high points on the plate, but it will take a long time to do this by hand. I looked in the workshop manual and I cannot see any reference to maximum permissible run out.

They need to be rolled flat, the pressing operation distorts them and they should have been rolled afterwards, your method will work but you may loose thickness.

kommando wrote;

they should have been rolled afterwards

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Thanks kommando.

They may be O.K. and not impede the clutch operation, I don't know as I haven't tried them yet. I must say though that I am dissapointed.

These are one of many parts that have had to be altered to fit. For example, I bought a new frame from Andover Norton, and amongst lots of other things, a new rear mounting stud (engine to frame) and the stud would not pass through the hole drilled in the frame. I thought that this would have been caused by the thickness of the paint, and so filed it away down to metal. The stud still wouldn't fit. In the end I had to drill the hole out! On a new frame aaaahhggrr!!! And then there was the new wiring harness that had extra wires running to the alternator for no apparent reason, and the wires for the warning light control unit exiting the harness near to the head steady instead of near the battery carrier. I could continue....but I will not. Sorry about that. Rant over!

I am not all that suprised by all this , but having been away from Nortons and classic bikes for 12 or so years I had kidded myself that things would have improved since then. Ah well, it just makes the satisfaction of getting things sorted even greater.

Hi Reggie,
Send the plates back and tell them why they might not be aware of any problem.

Cash, yes I will probably ring them up and have a chat about this.