Rev counter

Information relating to the Matchless G80 or AJS Model 18 500cc Heavyweight.
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MrB
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Rev counter

Post by MrB »

Is it possible to fit a rev counter to a 56 G80S.
Andy51
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Re: Rev counter

Post by Andy51 »

To fit an original chronometric tacho would be expensive (assuming you could find one in the first place!) and would require a replacement outer cam cover with tacho drive and probably a replacement exhaust cam. You would also lose the ATD, as these cannot drive a tacho. All in all this is not a realistic way forward but you can get modern electronic replica tacho from Smiths, see https://www.digital-speedos.co.uk/gauge ... meter-p212. These look the part but appear to fit straight on without the mechanical changes required by an original part and at £245 would be a LOT cheaper than a chronometric and drive. I have been considering one myself and if you take this route would appreciate your experiences. Andy
MrB
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Re: Rev counter

Post by MrB »

Many thanks for the reply and info. Seems the one listed is out of stock at the moment so still looking for another solution.
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Pharisee
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Re: Rev counter

Post by Pharisee »

Not a G80, but I fitted a tachometer to a Norton ES2 engine, which is very similar. I machined the mag/dyno chain cover to accept a cable drive gearbox. To drive it, I made an extended nut with a slot machined across it. That engaged with the tang on the gearbox. It all worked very well. I apologise for the quality of the photos, but they are the only ones I have. The engine was painted with a heat dispersant matt black paint. I've recently been thinking about doing the same to my G80CS. Adding a tacho, not painting it black.
Bike019a.jpg
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Last edited by Pharisee on Mon Nov 22, 2021 9:27 am, edited 1 time in total.
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Samuel
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Re: Rev counter

Post by Samuel »

Pharisee wrote: Fri Nov 19, 2021 10:26 pm I apologise for the quality of the photos, but they are the only ones I have.
They do not seem to have come through at all...
Sam
MrB
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Re: Rev counter

Post by MrB »

No I can`t see them either.
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jackstringer
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Re: Rev counter

Post by jackstringer »

The pics can be found by right click and opening in a new window. I suspect the site has hotlinking protection.

Can you not just fit a tachometer that takes pulses from the condenser/point etc.
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Pharisee
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Re: Rev counter

Post by Pharisee »

Samuel wrote: Sun Nov 21, 2021 2:38 pm
Pharisee wrote: Fri Nov 19, 2021 10:26 pm I apologise for the quality of the photos, but they are the only ones I have.
They do not seem to have come through at all...
Hopefully you can see them now.
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griffin
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Re: Rev counter

Post by griffin »

Samuel wrote: Sun Nov 21, 2021 2:38 pm
Pharisee wrote: Fri Nov 19, 2021 10:26 pm I apologise for the quality of the photos, but they are the only ones I have.
They do not seem to have come through at all...
With pictures I always have to login again. Go to the top of the page.
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