Author Topic: A10 cylinder and head on A7  (Read 378 times)

Offline perlut

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A10 cylinder and head on A7
« on: 26.03. 2025 09:30 »
Will a A7 1953 work with a A10 cyl and head?
It is the setup on a object a bought.

Offline rocker21

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Re: A10 cylinder and head on A7
« Reply #1 on: 26.03. 2025 10:26 »
yes but not very well, comp ratio will be reduced and the combustion chamber shape will be wrong.
1960 A7S motoguzzi Monza 500, motoguzzi V7III special, new triumph speed 400
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Offline Swarfcut

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Re: A10 cylinder and head on A7
« Reply #2 on: 26.03. 2025 10:52 »
  Both A7 and A10 heads fit either cylinder barrel, the headbolt positions are the same. Cylinder bores are different but if there is nothing else available these parts can be made to work.

 Have you really got the wrong barrel?  A7 has 7 fins, A10 has 8. Could be it is A10 inside, fitted into A7 stamped crankcases.

 Now get over to the introduction section and tell your backstory. Welcome along.

 Swarfy.

Offline muskrat

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Re: A10 cylinder and head on A7
« Reply #3 on: 26.03. 2025 17:57 »
G'day perlut  *welcome*
As Swarfy said A7 & A10's are very similar and parts can be swapped. After 70 years all sorts of things could/has been done to it. Count the fins on the barrels is the easiest way.
An intro and pictures would be nice.
Cheers
'51 A7 plunger, '57 A7SS racer now a A10CR, '78 XT500, '83 CB1100F, 88 HD FXST, 2000 CBR929RR ex Honda Australia Superbike .
Australia
Muskys Plunger A7

Online Peter in Aus

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Re: A10 cylinder and head on A7
« Reply #4 on: 27.03. 2025 00:53 »
I fitted a A10 head to A7 engine with .060 oversize bore worked fine for me *smile*

Busselton West Australia
49 A7 longstroke
58 A10  SA

Offline Black Sheep

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Re: A10 cylinder and head on A7
« Reply #5 on: 27.03. 2025 06:33 »
Worked fine on my A7. It went rather well!
2 twins, 2 singles, lots of sheep

Offline perlut

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Re: A10 cylinder and head on A7
« Reply #6 on: 27.03. 2025 06:57 »
Tnx for your answers.  *smiley4*

I'll will try to post some pictures tomorrow.