Hi everyone this is my first forum iv ever written so not sure if im doing it right but here goes.
iv recently bought a 1988 Honda NS250R MC11 and its all in pieces from the previous owner who had planned on rebuilding it but never found the time to do it. so therefore its now my plan he told me that it needs new pistons and heads and im unsure on what sized pistons to buy because iv searched all over the web and can only find parts and manuals for the MC16 to the MC28. nothing what so ever on the MC11 other than in the model history section on this website.
If i could have any help as to which pistons to buy or if all the NS250R range all have the same piston size then i would be really thankful.

Guy

Hi Guy,

The NS250R MC11 pistons were sized A, B, C, A being the largest C being the smallest, although there's hardly any difference between them all, none of the standard pistons are available from Honda now so aftermarket pistons from another model have to be used, ideally you would want to replate the cylinders when fitting new pistons.

Another option would be to fit a used set of cylinders and pistons from the NS400R as they will fit straight on and increase capacity to around 260cc. Another option if you use the 400 cylinders (250 cylinder walls are thinner) is to bore them out, both 300cc (61mm) and 320cc (63mm) are possible with re machined heads to suit.

If you need any more info please PM me.

Cheers Ian

Hi am in Palmerston North we can work toghter to find pistons also i have wiring diagrams from the guy i brought my Honda ns 250 r from i scan them tonight