Author Topic: A7 / A10 Crank ?  (Read 1033 times)

Offline A10Boy

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A7 / A10 Crank ?
« on: 10.07. 2009 14:24 »
I just took delivery of a good large journal crank for the old flash, I was cleaning it up and noticed the letters "A7" cast into the flywheel. Now I am concerned that its an A7 flywheel on an A10 crank. ?? Am I right in thinking A7's never used the large journal crank?

In all other respects it looks the same as the old crank, there is a slight difference in the casting of the flywheel but the crank overall weighs approx the same and has the same dimensions. The sludge bungs are the same size as the original A10 crank. Any ideas, maybe its one of those things where the casting manufacturer didn't change the numbers and they don't mean anything ??

Are the two types so different that they cant be mixed and I'm worrying over nothing ?

 *conf*
Regards

Andy

1960 A10 - Black Golden Flash
Plus
1974 Kawasaki Z1a
Yam XJR 1300

Offline Goldy

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Re: A7 / A10 Crank ?
« Reply #1 on: 10.07. 2009 18:47 »
The main measurement is the stroke ie the centres of the crankshaft and big end journals. TheA7 is 72.6mm and the A10 is 84mm.
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Online trevinoz

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Re: A7 / A10 Crank ?
« Reply #2 on: 11.07. 2009 01:22 »
The A7 never had a large journal crank therefore there would not be a flywheel suitable for an A10 crank.
An A65 flywheel will fit an A10 crank
 Trev.

Online BSA_54A10

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Re: A7 / A10 Crank ?
« Reply #3 on: 11.07. 2009 08:14 »
Quote
The main measurement is the stroke ie the centres of the crankshaft and big end journals. TheA7 is 72.6mm and the A10 is 84mm
X 2
Bike Beesa
Trevor

Offline A10Boy

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Re: A7 / A10 Crank ?
« Reply #4 on: 11.07. 2009 10:43 »
Cheers guys, I thought the A7 had never used the three bolt Large Journal crank, and if I had looked in Roys book its there in black and white.

Opps

 *red*
Regards

Andy

1960 A10 - Black Golden Flash
Plus
1974 Kawasaki Z1a
Yam XJR 1300