SOHC 350cc Pre 1948 40M(Magnesium Crankcase) Rear Engine Plates - Pair

These rear engine plates are laser cut, using original SOHC Manx engine plates as an original and are to fit 1935 - 48 350cc M40/Manx chassis (both rigid and plunger frames) and magnesium 350cc racing crankcases.

The magnesium 350cc crankcase type was slightly smaller than the 500cc type, however, after 1948 the crankcase of both models was standardised on the 500 castings.  Therefore if you are not sure which type crankcase your 350 engine has, please email our Sales email

- Note: It is extremely difficult to find two original Manx frames of this era with exactly the same engine lugs, they can often vary by a small amount.  Therefore I can also supply these engine plates with the hole for the frame mount left blank if desired. I will also supply both sets if required, and you send back whichever set you do not use. Please request this when ordering.

Plates come linished and lightly oiled

Price is per pair