mystery motor. HA2 rod, 3.4mm spacer & 70mm piston. what is it?

[SatisTraction]

i got another mystery motor on my hands. The rod says HA2 and the cylinder has a .190" spacer under it. the piston is 70mm. it looks like a wiesco but the number is too pitted to see. cany anyone help?

[Qracer]

ha2 is a long rod crank, the .190 spacer is usually used with 85-86 style pistons with the long rod crank. Is it a stock cylinder or aftermarket?

[SatisTraction]

stock. thanks for the help. I mis-measured the piston. :D

it is 67.69mm and the bore is 67.92

[wilkin250r]

Your math doesn't add up. Your title says "3.4mm", but your post says .190"

.190"=4.86mm

[86 Quad R]

there is roughly .009" piston to cylinder clearance. bout time for a re-bore. chances are that is a wiseco piston. is the sleeve the thick stock big bore replacement? what head came with it?

[wilkin250r]

Originally posted by 86 Quad R
there is roughly .009" piston to cylinder clearance. bout time for a re-bore.

0.009" clearance is bad, but that might all be piston wear. A new piston might bring it right back to spec.

[SatisTraction]

it is a stock cylinder. got it all figured out now. :D