DO ALL ‘TUNING’ METHODS REALLY WORK? – PART 2

last month’s article I shared the results of a collection of modifications to the lower cylinder transfer area on a Gori 175cc kit. This was a piston-ported, simple, four-port cylinder with just two transfers (like the original Innocenti design). Each of the transfer ports is fed from a single case entry area/section of the duct and directed out of a single cylinder-wall exit area. These are all fed from (in that case) a 28mm carb and silenced by a Clubman exhaust. The total power from the package sat at around 17hp. The same previous article showed that the result of applying the well-known and widely used tuning modifications was little (almost zero) benefit, especially for the effort put in. Though at least it was