Mainshaft Wear

Information relating to the Matchless G2 or AJS Model 14 250cc Lightweight
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Martin.S
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Mainshaft Wear

Post by Martin.S »

Are the splines meant to be like this on the clutch end of the mainshaft - I think not but I have two and they're both the same.
IMG_20181125_160458.jpg
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Ozmadman
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Re: Mainshaft Wear

Post by Ozmadman »

No, probably a knackered clutch centre that has done it, they are expensive and maybe the PO'S have skimped on the maintenance in the past
Last edited by Ozmadman on Sun Nov 25, 2018 5:04 pm, edited 1 time in total.
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Mick D
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Re: Mainshaft Wear

Post by Mick D »

Hi

No - that's wear in my opinion, but I'm struggling to see how it's caused.

Regards Mick
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Rob Harknett
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Re: Mainshaft Wear

Post by Rob Harknett »

Well, its probably because its 50 years old. I have seen wear like that, to which an old soldier who repaired WD bikes during the war said, that's not scarp yet. That was when a part was really scrap, before it was scrapped. They need to be in better shape now, to sit in a shed waiting for a sunny day, before taken on a gentle ride in the countryside. I have prewar bikes with worn splines. After some 30 years and a few 1,000 miles of runs. I stopped looking for better shafts long ago. Was the bike telling you something was wrong before you saw the wear?
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Janet
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Re: Mainshaft Wear

Post by Janet »

Mick D wrote:Hi

No - that's wear in my opinion, but I'm struggling to see how it's caused.

Regards Mick
It's simple. Two parts, the shaft and the clutch centre fit together on these splines. They are not welded together so over the years every acceleration or deceleration creates a teeny-weeny bit of movement between the two. At first the wear isn't noticeable but the more use the bike has, the more wear there is on both parts, and therefore the bigger and more damaging is the clunk each time, and so it goes on. It's made worse if the clutch centre has ever been loose. The same type of wear can develop on any splined shaft.

I'm sure you knew all that.
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SPRIDDLER
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Re: Mainshaft Wear

Post by SPRIDDLER »

My attitude is that if it isn't giving trouble and it has lasted 20, 30 or 50 years and tens of thousands of miles it'll probably see you out ;)

I had a scalloped H/W drive shaft that had been fine and was still working o.k. after 15,000 miles with me (and goodness knows how many more previously) but I did replace it whilst stripped to replace the failed big end as I was preparing for a two month (3,400 miles) foreign camping trip....
Scalloped mainshaft enl 2.JPG
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Mick D
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Re: Mainshaft Wear

Post by Mick D »

Hi Janet

You're right of course - I did know that ;)

But the clutch centre nut 'should' stop relative movement between the centre and shaft. In the event that it didn't I'd expect wear to be fairly linear along the splines but in this case they've worn to a curve, (or is that a photographic anomaly?)

Regards Mick - still perplexed :)
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Martin.S
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Re: Mainshaft Wear

Post by Martin.S »

Me too - I would expect to see the ends of the spline to wear first with the clutch hub rocking about when loose but not the middle - that's why I asked.
G15 Roy
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Re: Mainshaft Wear

Post by G15 Roy »

You may be in luck as this part is on the list of parts for the club to be remade soon at a target price of just under £200.00 once we have a suitable sample.
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Re: Mainshaft Wear

Post by shifter »

I have just hunted this one out after reading this thread, it was in among a box of bits and bobs I have it looks a good one

shifter
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