Will the fuel filter from an MC28 fit the 21?

Probably a stupid question, but I can't find anyone with the MC21 part number in stock.

Second question, I built my bike with 1mm Squish. Is it worth using the RS gaskets to reduce that by .1mm?

Is there any gain?

Not too sure about your fuel filter but I would certainly try for a tighter squish. 1mm is too much. .68 to .7 is better. This is, of course, is assuming that your big and small ends and rods are in good nick.

It never ceases to amaze me how you can go from a 3.5cc motor through 100cc and upwards and the squish remains VERY similar on all motors. Two strokes of course.

Mike