Author Topic: A7SS update and Camshaft query.  (Read 212 times)

Offline Mosin

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A7SS update and Camshaft query.
« on: 26.10. 2018 11:22 »
Well it is now over four years since the fateful day when my A7SS destroyed its engine and pretty much acted as a metaphor for what was going on in my marriage at the same time! On that fateful day in 2014 I was just about to move to start a new job in Scotland and had no time to do anything with it, so just wheeled it into a friend's garage and took my modern-ish (1994) Triumph instead. I lived in my motorhome on the Isle of Bute for three years and only moved back to England about 12 months ago, when I finally got around to stripping down the engine on the BSA. I was pretty horrified with what I found. One of the con-rods had shot straight through the top of the piston and the engine looked like a hand grenade had been detonated inside the barrels.

Anyway, mercifully, the crank and casings were ok, so I am now well on the way to getting the whole thing rebuilt with new barrels, con rods, pistons, valves, camshaft, followers, a professionally refurbished head with a view to being back on the road in time for the spring. I have now sourced most of the parts I need, but am looking for some advice on which camshaft to go for. My new pistons are 8:1 compression ratio and the choice seems to be between the 67.0356 or 67.0357. Both seem to have been fitted to alloy head A7s but the more I read on the matter, the more confused I get!

I would welcome any thoughts or suggestions which forum members may have on the pros and cons of these two camshafts.

As always, thanks in anticipation. It's good to be back!

Mosin
1960 A7 Shooting Star
1959 D3 Bantam
1994 Triumph Trident 900

North West England

Online Greybeard

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Re: A7SS update and Camshaft query.
« Reply #1 on: 26.10. 2018 13:51 »
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Online Black Sheep

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Re: A7SS update and Camshaft query.
« Reply #2 on: 26.10. 2018 14:28 »
Both my A7 and A10 are running on 357 camshafts but I reckon that for real world riding you are better using 356 cams which your bike would have had originally anyway.
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Online muskrat

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Re: A7SS update and Camshaft query.
« Reply #3 on: 26.10. 2018 19:51 »
G'day Mosin.
357's in both of mine but it all depends on your riding style and conditions. Spirited country miles (between pubs) would suit the 357 where as around town and carrying load (the missus) the 356 would be better.
Cheers
'51 A7 plunger, '57 A7SS now A10CR, '76 XT500, '77 AG175 '83 CB1100F, '81 CB900F project.
Australia
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