I am building a px200 with a polini 208cc kit. The scoot has a 60mm crank. It seems I have two options for the head. 1). I use a head with standard squish and add a 1.5mm basegasket on the cylinder, or 2). I buy a head machined for use without such packing, as advertised in the SIP catalogue (I think worb5 make it)
Can anyone give me an idea as to the different performance characteristics of either set-up? I have seen plenty of engines using the 1.5mm gasket, but never one with these other heads. Want to make sure ther’re OK before buying one.
Also, I have just the standard polini kit, and believe I need to get it honed to reduce my chances of seizing. Does anyone have figures for the amount of clearannce I need to aim for?