Piston differences '69 to'70

[ThumpStreet]

Good day to All.Can any of you salty XL guys out there educate me on the differences between the XLCH pistons years 1969 to 1970.Example:22257-58A year 1969 XLCH .050 O.S.vs.22257-70 1970 XLCH .050 O.S. Weren't the bore sizes in 69 to 70 the same starting point of 3.00" ? Were there dome changes?Is either application an acceptable replacement part?

[sportsterpaul]

Most likely the clearance cutouts for the valves. See Dr. Dicks explanation of cylinder heads for 900cc
http://xlforum.net/vbportal/forums/show ... stcount=64

from the thread
http://xlforum.net/vbportal/forums/show ... p?t=166440

So my suspicion is you could use the later pistons in the earlier engine, but not the other way around-- since the valve might clank into the piston.

Hang on, sure the experts will weigh in with the exact answer.

[ThumpStreet]

Excellent information in those reads.Much thanks for pulling those posts and placing them in front of me.Saved time getting right to the meat of the subject.This project I've gotton into is an old girl that needs a lot of help.