Topic: Increase capacity of CB750 to 750

[chris]

What are the best pistons to use to increase the capacity to 750 and the Comp to 10.5 to 1 or similar

[Retro Rocket]

What are the best pistons to use to increase the capacity to 750 and the Comp to 10.5 to 1 or similar

What are you trying to do?  If you are after more power then get the head worked on, porting, valves and so on and if you want more compression just get the head shaved. The 736cc is plenty enough with some head work to make these old girls fly.    I have never seen a 750cc piston kit for one of these bikes.

Mick

[MCRider]

What are the best pistons to use to increase the capacity to 750 and the Comp to 10.5 to 1 or similar

1/2 mm over stock is 748.5cc. For those of us who ran in dispacement capped classes, Yoshimura made a 2 ring slipper piston for this purpose. I doubt they are available now.  I have a set.

http://www.bgsoflex.com/displacement.html

Forum member KOS at m3racing.com has 62mm blanks (make your own dome) for 760cc, which I'm guessing is AHRMA legal or he wouldn't have them. http://www.m3racing.com/products/parts.html  A bit pricey for less than a racers budget.

I would call ARIAS Pistons if I simply had to have them, as they have blanks for nearly everything. Probably pricey as well. Unless you're racing and restricted to 750cc, use stock pistons and head work first, add a pipe and carbs for a really sweet sleeper engine.

Actually, KOS has the 62mm WISECO pistons that have pockets as well, I missed that in skimming his catalog. Still a little pricey unless you have to have them.

[Ecosse]

http://www.bgsoflex.com/displacement.html

very nifty ron! was this in faq?

[MCRider]

http://www.bgsoflex.com/displacement.html

very nifty ron! was this in faq?

No I have a few booked marked. Originally did a google search on "engine displacement calculators".

Just about every calculator imaginable is on the web now for free. The internet is great!