Author Topic: Crazy overbore combos? cb650 overbore project.  (Read 1327 times)

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Offline Soos

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Crazy overbore combos? cb650 overbore project.
« on: January 14, 2009, 05:58:40 AM »
Ok Being WAY to inquisitive, I have found on another forum(will find link later) that the cb750 836 pistons can be used as an overbore kit for the (??) kz650.
HOWEVER, the 836 cb750 pistons are about 8mm(? have to check that post again) shorter in deck + dome height compared to the stocker pistons, but same wrist pin diameter.
Mabey it was a GS650.... ?

They all agreed it was basically not feasible on a reasonable budget.



Whilst I was thumbing around(hunting for a socket) in my garage while putting my freshly mounted anakee's on my '79cb650,  I came across some measurements I had made of the cb650 conn. rods, and cb550 conn rods.

The 550's rod I have is 5mm shorter center to center than the cb650's is.


The combo of those 62mm pistons(or were they 64?) and a set of cb550 rods(do they make falcon or any other aftermarket cb550 rods?)
Going into the garage in a minute to measure the width of the 650 and 550 rods to see if the crankshaft bearing rod end width will be an issue.

I'm all about cheap and re-cycling.

MY other 650 already has cb750 stockers in it as an overbore.
There has to be something......



Has anyone ever used a set of non-honda pistons as an overbore in a cb650 before??

Yammy likes 16mm wrist pins I am have found out... :(
(or at least on the pistons big enough to get my attention)





l8r
« Last Edit: January 14, 2009, 06:01:23 AM by SteveD CB500F »
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"Brix will be shat by your neighbors." - schwebel
(61mm)652cc 1979 cb650

Offline Soos

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Re: Crazy ocerbore combos? cb650 overbore project.
« Reply #1 on: January 14, 2009, 06:00:19 AM »
But basically the 5mm shorter rods would help offset the higher deck+dome height of those other pistons...

probably a bit of machining for the other pistons nonetheless, but so be it.




l8r
-=≡ Soos ≡=-
Just think to yourself what would Alowishus Devander Abercrombie do?
"Brix will be shat by your neighbors." - schwebel
(61mm)652cc 1979 cb650

Offline Pinhead

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Re: Crazy overbore combos? cb650 overbore project.
« Reply #2 on: February 13, 2009, 07:04:20 PM »
Wow, I can't believe this thread hasn't gotten more attention. Must be due to the red-headed stepchild status of our 650s. ;)
Doug

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