500cc Dragonfly barrels and pistons

[P10]

Pair of new linered aluminium cylinder barrels for 500cc Dragonfly conversion complete with a pair of new boxed pistons, rings, gudgeon pins, circlips and compression plates. £500.

[Ray Dodds]

Helo do you know if they will fit Mk engines, Regards Ray.

[P10]

Sorry Ray but I am not an expert on Douglas engines.  I have a Dragonfly and only know their condition and that they were made for that model.

[eddie]

Ray,
        The Dragonfly barrels are much shorter than the Mark barrels and have a different stud configuration on the base. Also, these barrels can only be fitted to the Dragonfly after the crankcase mouths have been bored out to accomodate the larger liners.

  Regards,
                Eddie.

[jimbo]

Hi Ray,

    Are the alloy barrels still for sale? I would be interested....

                                                                                   Jim

[Paul Taliesin]

Does anybody know who made these 500 alloy barrels? Anybody in the club?
Would be very interested to get my hands on a pair? How did they work out on the bike more torque and performance?

[eddie]

Paul,
        I think these barrels were cast from the pattern for the barrels on the black and silver Dragonfly special that we spoke of in a previous posting. There were some extras made, but they were sold off at a Douglas Club rally several years ago. The biggest problem is finding suitable pistons to use with them - flat twin pistons have the valve cutaways in line with the gudgeon pin instead of at 90 degrees to it.

  Regards,
               Eddie.