Hi Steve!
I'm running my A10 on 9:1 and have no problems kickstarting it, even off the main stand.
It mainly is a matter of the right technique, not necessarily pure power. Even my younger brother is able to kickstart it (he's 16 and has maybe 70 kg or so). I have to admit he has some experience with Enduro machines though.
This is the procedure I follow:
Retard ignition first (automatic on mine, probably yours is manual?). Sorry if this is being too obvious, but forgetting it is not the best idea.
Push the kickstart down gently, until you feel the resistance. You are now somewhere before TDC.
Now release the kickstart and allow it to move upwards until being in a horizontal line, or slightly above.
Gently push the kickstart down, just enough to feel the resistance, but not so much as to push it down further. Rest in this postion for a few seconds, thus allowing the pressure in the combustion chamber to reduce a bit through the piston rings. This makes it much easier to kickstart. If you have the pistons down on BDC and stomp on the kickstart lever, you will notice it is significantly harder to get the psitons over the compression stroke.
Now give it a good hard kick, not stomping or jumping on the lever, but swinging it down forcefully with the full weight of your body behind it.
If there's no way the high CR will work for you, there might be a way of reducing it without buying new pistons. There is a chap called Peter Weigelt in Germany who sells CR reduction plates. I've never seen them advertised elsewhere.
However, here's Peter's address and phone number:
British Bikes Weigelt
Alte Darmstädter Str. 22
64521 Groß-Gerau OT Dornheim
Tel. 0049 - (0)6152 98 78 18
Here's the link to the plates:
http://www.bb-weigelt.de/pbuchs.htmThe German text basically says:
"As BSA A10 and TRI T120 engines with a CR of 9:1 always tend to ping, we had compression reduction plates manufactured for these models. These plates are made from aluminium and are fitted between the crankcases and the barrels using two gaskets.
Often people don't consider that the CR increases significantly when boring out the barrels. Retarding the ignition to reduce the tendency to ping let's the engine run at higher temperatures, a bad solution, especially for OIF models."I actually don't know whether Peter speaks English, but I'm pretty sure he does, as he is dealing with brit bikes and spares since years. If not, I might act as interpreter if necessary.
Cheers, Markus