28 or 32 degrees before top dead centre?

A surprise to me that an Atlas should be that sensitive to timing that it don't start if timing fully advanced is 28 or 32 degrees. Of course optimum performance differs. My Manx is easily push started if timing (fully advanced) is anywhere between 12 ATDC! or 40 BTDC.

Most likely poor fuel delivery or dirty plugs .Even a well set up Atlas with good compression can be hard to start if you are a lightweight. Aim for 28 degrees. About time for some low CR pistons for all those aged Atlas and Commando owners. Or a compression release conversion to the exhaust valve covers.

Back in the days of big singles, the large stroke (88mm even for the 350 bikes) gave the piston a bigger mechanical advantage against the kick start than the 72mm against only 250cc per pot with the Dommie. But with the Atlas's 375cc and 99mm stroke, plus much higher compression, gives kick start force bigger than a prewar 350 single,which would have had a decompressor. No wonder the 750 twins are tough to start...can a decompressor be rigged without wrecking the valves? Or are flywheels not heavy enough to make it worth while?

Is it fresh summer fuel? Will it start with EasyStart?

Steve