Author Topic: A10 crank in X65  (Read 1740 times)

Offline terryk

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A10 crank in X65
« on: 25.01. 2010 04:45 »
I notice they used an A10 crank in this X65 BSA on the SRM website has anyone used a crank out of an X65 or A65 etc in an A10? I dont know anything about unit BSAs. Can a crank be made to fit? Just a thought cause A10 cranks are getting hadrer to find.

1950-53 A10 rigid/plungers, 1958-61 A10 super rockets, 1947-50 A7 longstrokes, 1949 Star twin,
1951-54 A7 plungers, 1940s M21, WDM20s,
1948-50s B33s rigid/plunger/swingarm, 1948-50s b31s rigid/plunger/swingarm

Online Brian

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Re: A10 crank in X65
« Reply #1 on: 25.01. 2010 05:11 »
I havent seen the bloke or the bike for a couple of years but there is a bloke down this way that built a A65 with a A10 crank. I dont know a lot of detail such as how he fitted the alternater, unless it was a super rare alternater A10 crank. Dont know what rods or pistons he used, anyway he ended up with about 750cc and easily the smoothest A65 I have ever ridden.

I have always thought A65's are one of the best designed british twins ever, unfortunately they vibrate that much they are almost unrideable.

Here is a pic of my 1970 Thunderbolt, I gave it to my son as an act of revenge !

Offline trevinoz

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Re: A10 crank in X65
« Reply #2 on: 25.01. 2010 08:34 »
The A65 crank would be a little short in the stroke for an A10.
Maybe it could be fitted to an A7 with special pistons.

Offline olev

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Re: A10 crank in X65
« Reply #3 on: 25.01. 2010 11:45 »
A10 cranks in A65s wern't uncommon in sidecar racing in the late 1960's.
Chris Vincent won the 1970 British sidecar championship on a bored out A65 with an A10 crank.
Les Mason (devimead) apparently made a mother with special barrels that took B44 pistons and with the A10 crank gave 840cc.
There was a rumour he made another with an A70 crank which had a 85mm stroke. (I notice he got other people to ride them)
I asked a similar question re A50 cranks a while back and backed away from any ideas after Alex's post.,1355.msg9679.html#msg9679