Topic: So, why not these 550 overbore pistons?

[Scott S]

 Since the 592/605cc kits seem to have their own issues and I'm having a hard time finding someone to do the modded 750 pistons, why not just do a 1.00mm overbore and simplify things?

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=360391815085&ssPageName=ADME:X:RTQ:MOTORS:1123

 I can use stock gaskets, there'll be plenty of material left on the sleeves, and I'll go from 544cc (stock) to 563cc.
 Coupled with a ported head, CB650 cam, jetted carbs and a 4-1 exhaust, I should see and feel a meaningful bump in power, right?

[Scott S]

 I'll take it that no reply means that they're OK...

[kerryb]

They might be good parts, I just went by that shop on my sunday ride, they are good people.  The other question is...If it all goes horribly wrong during assembly, and you break a ring, can you get a replacement?

I would hate to go to all that work and be stalled for lack of parts.

[Fritz]

Hi,

I've used pistons of the same source for my engine rebuild - 0.25mm overbore:
http://www.cmsnl.com/products/piston-100repro_06135374000p/
I could not see any differences in quality between them and the Honda pistons. They are machined to the same dimensions, so you will be able to use Honda rings if you ever need to replace and get a hold of them.
Until now, I did about 3.000 miles on these pistons without any problems.

Increasing the displacement by 3.5% does not sound like it will give you so much more power that you can feel any difference. But if you need a fresh bore and new pistons anyway, 1mm overbore will not hurt, I think.

650 cam and ported head is a whole different story.

Cheers
Carsten

[Danno]

it probably will not give you more real seat of the pants power but will increase low to midrange torque which is exactly what it did when honda overbored the 500 to 550 

the 650 cam will give you a little more punch but porting the 550 will do the best for it as it can add 10 hp  which is definately noticeable