Author Topic: A7SS Pistons  (Read 959 times)

Offline Tukig

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A7SS Pistons
« on: 20.07. 2012 18:38 »
Hi everyone,

Engine is finally away being rebuilt following a big end seizure. All going well with end feed conversion and new Thunder Eng con-rods (they are so beautiful it's a pity that they have to go on the inside of the engine). The problem now is that +40 thou pistons (or any decent quality pistons of any size) seem to be un-obtainable. Does anybody know of a source or has anyone any experience of other pistons from another motorcycle that can be made to fit. Thanks as always.

Gary

Online muskrat

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'51 A7 plunger, '57 A7SS racer now a A10CR, '78 XT500, '83 CB1100F, 88 HD FXST, 2000 CBR929RR ex Honda Australia Superbike .
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Offline Tukig

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Re: A7SS Pistons
« Reply #2 on: 24.07. 2012 22:32 »
Thanks Muskrat,

I'll call them tomorrow. I notice they have different prices for the same size (give or take a bit for metric and imperial) piston, I presume they must be different makes and probably different quality (maybe?). I'll let you all know.

Cheers

Gary

Offline Tukig

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Re: A7SS Pistons
« Reply #3 on: 31.07. 2012 20:55 »
Hello Again,

Some snippets of the collective wisdom would be appreciated. I've got a choice of pistons (Oh how I dislike choices when I can't make an informed decision!). Do I go down to 7.25:1 or stick with the 8:1 what with modern fuel the way it is etc.

Thanks

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Re: A7SS Pistons
« Reply #4 on: 01.08. 2012 10:18 »
 I'd stick with the 8's. It's not till you get up to 9-9.5 you have to worry about pinging but I wouldn't use less than 95 octane.
I'll be looking for a set myself for the '51 ('57 SS top end) soon.
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

Offline Tukig

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Re: A7SS Pistons
« Reply #5 on: 01.08. 2012 11:27 »
Thanks for that. I was leaning that way but its good to hear from someone with practical experience of these things. Right then lets give the credit card another bashing. Last time I bought pistons was for a T140V about 20 years ago, they were about £0.38 if my memory serves me right!