Is it wrong...

[Arthur John Smithsplease]

Now I wouldn't bother with the adaptor on the leather sealed piston to convert to a synthetic seal for three good reasons.

1) John Knibbs is knocking out synthetic sealed Pistons complete with seal at £30.

2) The adaptor adds 27grams to an already heavy piston.

3) The adaptor reduces the already short stroke of the leather sealed piston by another 4mm.


Here's the three strokes and weights of the three setups :-

Factory Synthetic sealed piston ------------- 69mm stroke - piston weight 264g

Factory Leather sealed piston --------------- 65mm stroke - piston weight 294g

Leather sealed piston adapted to synthetic - 61mm stroke - piston weight 321g


Saying all that I do like to start off with the old leather sealed piston as you can machine the nose back easily to end up with a lightened piston with a 71mm stroke.




All the best Mick

Sorry, but did I read that right.

Are they made of nylon or carbon fibre for example.

Does the reduced weight of such a piston make for a much smoother action?

Or did you mean their own metal pistons with a synthetic seal?