Topic: honda cb 500 with 550 barrel or 605 bore kit?

[kranta]

so im wondering that i put big bore kit on it. so what kind a piston and cylinder i can put in stock bottom end?
can i put 605 kit on it or should i just put stock 550 pistons and stock cylinder? and where i can buy those big bore kits and pistons?

[Brantley]

I'm pretty sure you have to machine the 500's case to accept the 550's sleeves.  Give Dynoman a shout:
http://www.dynoman.net/engine/pistons/dp-CB550.html

[kranta]

yeah, i have heard that the center gearshift fork is really fragile. but bike isnt gone be racer only the daily rider.
but maybe i just put 550 pistons (58,5 mm) and jugs. it gone do few horsepowers more. but how i know
if i want to buy (60 mm) pistons and they are marked 0,25, 0,50 0,75 and 1,00. so where i can know what piston is what mm??

[bwaller]

The 0.25, 0.50 and so on means first overbore size, then second, then third. It would be a 60.25, 60.50 piston with each step.

After 59/60 mm the cylinder sleeves get very thin, and the "ramped edge" at the bottom becomes susceptible to chipping or damage. A 59 or 60 is the maximum size I would personally do in a 550 bore. And while larger bore diameters will increase the HP, good valve train work and porting of the head is equally effective and less involved. And porting is the foundation for better performance and mileage. (More air in, more power out).

The 550 sleeves can be bored for 61mm pistons safely, the sleeves are thin but reliable. (Larger than 61mm bore= dangerously thin) Honda's 58.5mm original bore then offered four oversizes. Any 60mm pistons (not OE) you find will be just that and no extra overbore sizes. Stock CB750 pistons are 61mm then again four oversizes.

As Cal mentioned there is hidden power in the head. Displacement is somewhat limited, but aftermarket cam selection is good and head work is the biggest potential in this middleweight.

The 550 gearbox is a whole improved design, but properly restored the 500 box can be reliable too. Shift forks can be hardwelded & ground, lots of newer options available for repairs including undercutting.

[kranta]

500 stock pistons are 56mm. so i think that i bored my jugs for 58,5mm pistons so its cc is then 550. right?
i have thinking too that i put 650 cam in it.  but this "more power" think is gone be next winter to do list.

[bwaller]

544cc. The 50.6mm stroke is the same between models.