I am setting up the top end on my Hare Scrambler and searched the archive to no avail. I have an Elko piston and need the deck height measurement. The shop manual lists heights for 2 different style pistons and I am not sure which the Elko falls under.
Thanks in advance
Chris
Chris, I am pooring thru manuals, seems like .040 to .047 X dimension will get you within reason.
The piston clearance can be as low as .002, but I do not rec. this.
...... the heat causes pistons to grow where the mass is, genererally @ the top, pistons are not true to bore, they do have non-linear proportions..they are tapered. Just measure one!
I rec. Swaintech coatings, even on new pistons to control the heat. with a ring end gap of .012 to .018 and a piston to bore fit of .035, you should be well within the the "envelope". Don't forget the oiling hole to cool the exhaust port bridge ...
Tom Brosius
My manual states that dimension X for engine type 54-250ccm
Piston #1274 =.9mm and #1274a=1.2mm. The american standard conversion of that = .0354" and .0473". I'd shoot for .040 if gaskets permit.
Raymond
Down East Pentons
Thanks Guys, the two piston styles listed in the shop manual had me confused. I'm off to the workshop to stack up some base gaskets.
Chris