Topic: Piston to wall clearance CB450???

[cb550fcafe]

I bought a factory service manual from Honda, read it cover to cover and searched, it does not give me the piston to wall clearance. I'm doing an over bore with some NOS pistons, so I don't have a spec sheet from the piston manfacurer, they are ART pistons, S3 over. Anyone have a size handy?

[MRieck]

I like cast pistons from a .001 to .0012.

[tbpmusic]

I haven't found that spec in any Honda manual.
Copy the manual pages with the cylinder/piston specs, take them to your machinist, along with the new pistons and rings.....
They have a standard value for the clearance they'll use, usually between 1-2 thousandths.
He'll make sure you end up with the right ring gap and all.

S3 would mean 3'rd over (0.75mm), but your machinist will measure them.
Stock is 70mm on CB450.......
Art is an OEM manufacturer of Honda pistons, you see the "Art" on out pistons all the time.

[lordmoonpie]

I'm running oversize wisecos in mine and they are machined up to 2 thou clearance. The guy who set up the pistons builds CB450s for the Isle of Man and has multiple machine wins to his credit so I'm pretty comfortable with his setup advice. Of course this is a race bike so you might want to vary the clearances for street applications?

[mlinder]

Yes, I'm about to do some racebike pistons too, and will be going loose. But for street, tighter is a bit better.

[City Boy]

Hi cb.I have a manual that lists a min. of .0012" and a max. of .002". for your model.Hope this helps.    Rock On

[tbpmusic]

Hi cb.I have a manual that lists a min. of .0012" and a max. of .002". for your model.Hope this helps.    Rock On

I'd really  like to see that - what manual is it???
Can you copy the page(s) and post it somehow??

[City Boy]

Hi tb.I am unable to post the info.It is contained in a book titled " Glen's Honda  Two Cylinder Repair and Tune-up Guide" by Harold T. Glenn.Printed in 1972 by Crown Publishers Inc. of New York.His acknowledgments names people from American Honda and Long Beach Honda as sources for pictures and technical info.The book covers models 125,160,175,250,305,350,and 450.     Rock On