The Classic MotorCycle

Two-stroke development

Much four-stroke development work, involving re-profiling cams, making higher compression pistons, revised cylinder heads and the like, is beyond the scope of most of us without access to serious engineering equipment. But useful two-stroke development can be carried out in the home workshop and even on the kitchen table using the basic kit in the photograph below.

True, if you want to skim heads to increase compression ratios or recast them to provide squish bands and/or alter combustion chamber shape, radically alter cylinder ports or add more, convert to disc valve induction, cast revised pistons etc you will need more than kitchen table tools and skills, but with nothing more than what is illustrated here you can go a long way to blueprinting your engine and you will then certainly have improved performance and/or gained fuel economy.

Some thoughts:

■ Some two-stroke development engineers (including the late Brian Woolley), scribes and observers have stated the only reason some makers bolt their two-stroke engines together is to prevent the loss of parts in transit from factory to customer, as they were unfit for use on arrival and they would dismantle them before running, and with

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