Hitchcocks Forum

Does anyone have the radial clearance figures for an accralite piston when used in an iron cylinder and an alloy cylnder?

I gather that for an alloy cylinder it is in the region of 0.0055 to 0.0060 and a little more on an iron cylinder, possibly 0.0060 to 0.0065.

Just wondering if someone can provide me with some real figures for bikes that they run.

I tend to ride mine fairly hard and I have it apart at the moment to fix an oil leak - I have noticed some light scuffing on the piston skirt, and I am running an iron cylinder. Been thinking about changing to alloy - better heat dissipation & lighter. I welcome all responses.

Search for Tom Lyon's Ace Products site in the US (sorry l don't have the address,) . He makes Bullet tuning parts and does some really interesting stuff. I seem to remember he has done some work on piston clearances with this combination. It's not as straightforward as it might seem! REgards, Mark

Thanks Mark, I have found an email address for Tom Lyons so I will see what that yeilds. While I have the bike apart I just want to do a good job on it. So I need to know if the iron cylinder can be honed out, or will it be oversize, or should I just bin it and go for an Alloy cylinder. I did try and contact Accralite but they were not exactly helpful which was rather dissapointing, our hosts have recommended 0.0055 to 0.006 which I assume is for an Alloy cylinder - I dont want to keep bothering them with a continual stream of emails so I am looking for people that have used these engines in anger for recommendations.