will Dragonfly pistons fit Mk engines

[Ray Dodds]

Will Dragonfly pistons fit Mk series engines or is there an alternative piston available ,ie japanese

[eddie]

Ray,
        Dragonfly pistons will physically fit in the Mark series engines, but I wouldn't reccommend it. The Dragonfly pistons are of the split skirt type and are prone to collapsing if worked hard. The favourite mod is to go the other way and fit Mark pistons in the Dragonfly. A more common mod on the 'Fly is to use Honda CB250N pistons - these are 62mm dia, so work out at +48 thou on standard size. The Honda piston has an odd crown shape but works well. The only other modification needed is to replace the small end bushes with ones with a 15mm bore.
  Hope this helps,
               Regards,
                            Eddie.

[Ray Dodds]

Thanks Eddie thats a gret help.