Laycock Overdrives

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Andy Stevens
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Laycock Overdrives

Post by Andy Stevens »

Which Laycock overdrive units can be fitted to a Jupiter or Javelin?

Andy :)
Keith Clements
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Post by Keith Clements »

Search this forum for 'overdrive'
Also
http://jowett.org/jowettnet/dt/tech/mod ... rdrive.htm
Also do a search for 'overdrive' on https://jowett.net/jowetttalk/

Overdrive Spares in Coventry can provide reconditioned overdrive with requisite adaptors.

I will attempt to find the relevant number on my units; I think they came from Triumph 1600 and Singer Gazelle
Last edited by Keith Clements on Fri Mar 26, 2021 11:09 am, edited 2 times in total.
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Andy Stevens
Posts: 92
Joined: Sat Aug 18, 2007 7:09 pm
Location: Haywards Heath

Laycock Overdrives

Post by Andy Stevens »

Thanks Keith.

No details tho on types!

'J' types seem to be plentiful at the moment...but can they be made to fit?

Is the 'D'type as used by Dave Kennedy the only one of any use?

Andy
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Post by Forumadmin »

There is a lot of machining to do to mate either the gearbox shaft or prop shaft to the unit. Dennis Sparrow does it one way and can get the adaptor plates made.

I went for the option that meant I just replaced the rear prop shaft and so was able to put back to normal in about half an hour between practice and race. Some circuits favoured O/D, others did not.

There are at least six ways I have seen them fitted to Jups and Javs. I decided not to modify gearbox which is one method, as they are not reliable and I knew at some stage a replacement would be needed quickly. You also irreperably modify a tailshaft.

Weight distribution was also important in racing.

The next one I do I will probably fit in place of the front prop shaft; but have not thought that one through yet. The reason is that the rear prop becomes much shorter and is thus under more strain. Not that I had any trouble in the long rallies; but mechanically it is not good and probably looses power.
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