Author Topic: Journal width  (Read 294 times)

Offline BSA500

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Journal width
« on: 30.05. 2018 09:05 »
Quick question what is the big end journal width on a a7 crank.
Thanks Andy

Online Peter in Aus

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Re: Journal width
« Reply #1 on: 30.05. 2018 09:25 »
Just measured my A7 crank on the bench 0.977in

Busselton West Australia
49 A7 longstroke
58 A10  SA

Offline muskrat

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Re: Journal width
« Reply #2 on: 30.05. 2018 09:58 »
G'day Andy.
I haven't got a crank handy so I measured a few rods.
Max side play of the rod on the journal is 0.024". All my rods (both A7 and A10) are 0.955" so that would make the journal width 0.979" MAX. I'd be comfortable with 0.020" side play making the journal width of 0.975".
Cheers
Peter got in 1st so we're pretty close.
'51 A7 plunger, '57 A7SS now A10CR,  '83 CB1100F, 88 FXST .
Australia
Muskys Plunger A7

Offline BSA500

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Re: Journal width
« Reply #3 on: 30.05. 2018 10:02 »
Thank you both. The guy who might be grindi g the crank needed the width

Offline muskrat

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Re: Journal width
« Reply #4 on: 30.05. 2018 10:07 »
And the radius should be no less than 0.090" and no more than 0.110". A lot of grinders mostly do cars/trucks and are reluctant to re-grind their wheels.
Cheers
'51 A7 plunger, '57 A7SS now A10CR,  '83 CB1100F, 88 FXST .
Australia
Muskys Plunger A7

Offline BSA500

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Re: Journal width
« Reply #5 on: 30.05. 2018 12:58 »
This guy does vintage up to modernish engines. He is also restoring one of two Amilcar racers  *smile*

Online Greybeard

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Re: Journal width
« Reply #6 on: 30.05. 2018 13:55 »
This guy does vintage up to modernish engines. He is also restoring one of two Amilcar racers  *smile*
Even so, make sure he understands about leaving the radii. Removing them will weaken your crankshaft.

Offline BSA500

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Re: Journal width
« Reply #7 on: 30.05. 2018 16:22 »
Yes I have a copy of the grinding service sheet