Author Topic: A7 tuning  (Read 1430 times)

Offline mrshells

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A7 tuning
« on: 08.05. 2009 18:02 »
Im looking towards building a spare but tuned engine for my A7
are there any particulaly good components to look for
what cam should i use ?
is there a head which is favourite for tuning ?
is 1 crank better than another  ? i know there are 2 types
whos best for balancing crank and rods ? and at what cost
  *conf* *conf* *conf* *conf* *conf* *conf* *conf* *conf*

Online Brian

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Re: A7 tuning
« Reply #1 on: 09.05. 2009 01:22 »
mrshells, being a Star Twin your bike is already "tuned". Assuming you have the correct components inside your engine you will have 7.25-1 compression and the 356 cam which is a very good set up for these engines. I have this setup in my 51' A7.

To go to a higher compression ratio and different cams etc would take you into a whole new area of unreliability and unless you are prepared to start spending money on bigger carby's etc would only cause problems. I really would advise to stay with the setup you have.

If you really want a bike with more power think about buying a A10 and leaving your lovely Star Twin as it is. Wouldnt it be nice to have a plunger A10 to go with your Star Twin. Now you might think that it would cost a lot to buy another bike but it might be cheaper than the potential problems caused by trying to "tune" your existing bike.

Proceed with caution .................................

Offline beezalex

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Re: A7 tuning
« Reply #2 on: 11.05. 2009 18:31 »
I agree with Brian here, but must also say that I am heading down that road myself, but for a purely scratch-built A7 road racer.  On the list: A65 crank, Triple rods and pistons, Alloy head with big valves and re-routed intakes, Megacycle X1 cam, the list goes on.  Lots of re-engineering of the A7/A10 weak spots, but it's gonna be fun,...

Too many BSA's