Board index Flathead Power-Technical Questions, Answers, and Suggestions Big Twin Flatties Cylinder bore

Cylinder bore

Moderators: Curt!, Pa

Post Sat Dec 28, 2013 1:42 pm

Posts: 158
Location: athens,greece
Hello again...
Found an old set of 11 fin 74 " cylinders...
Good condition over all but bored out to +.20
80" not
Would these need sleaving or can these be
Bored out even more to .30 or .40 over and still be ok...
if needed....
Thank you in advance...

Post Sat Dec 28, 2013 5:45 pm

Posts: 470
Location: Six miles East of Cheney, Wa.
My cylinders have an .060" bore, but have been sleeved.

What is wrong with a .020" bore? You said "good condition"....or are the bores a bit rusty?

I'm pretty sure they are safe out to .040", from what little I know...I will stand corrected if that is wrong. !!

Good luck.


Post Sun Dec 29, 2013 2:12 am

Posts: 158
Location: athens,greece
The cylinder walls were damaged... And need
Boring ... Wondering if to sleave or not...
Some one told me 74" cylinders +.50 with 80"
Pistons.... I am sceptical... Are the 74" cylinders
Thick enough?

Post Sun Dec 29, 2013 8:27 am
don User avatar

Posts: 571
Location: Spokane WA USA

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