Quote Originally Posted by Mach 1.5 View Post
Hi Mick. Back in the early 80s Venom would use the piston from the HW50 and use it in their HW55 conversion. As the 55 piston was to lite. Hope that helps in someway? Regards Mach 1.5
Hi Paul.

It's very difficult to say what model the piston I've been playing with in this 50 came out of as the action was bought off the Bay.

What I can say for sure is that it had a 65mm stroke and with the loss of a little metal to fit the TX seal it now weighs in at 186 grams, Presently with 69.5 mm stroke it has an overall length of 147.5 mm.
I'm now working on the assumption that the HW99 piston with its 71 mm stroke has an overall length of 146 mm, so by replacing the 10 mm wide HW seal with a 5 mm wide TX seal I could stroke it by 5 mm to 76 mm.
From measuring the cylinder this afternoon I've found that the compression chamber is 76.5 mm long and by winding the back block out the cocking linkage will still work with a 75 mm stroke so that's what I'll be aiming for now.

By using a HW99 piston rod and making my own piston body I could add weight to the body to get nearer to a 200 gram piston weight.






All the best Mick