Author Topic: S-12 CB500 pistons  (Read 1541 times)

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Offline MotoRico

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S-12 CB500 pistons
« on: March 19, 2006, 07:25:56 PM »
What bore are these? There is a set on ebay and I was wondering if they would work as a lesser over bore for a 550

Offline Big Jay

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Re: S-12 CB500 pistons
« Reply #1 on: March 19, 2006, 07:59:02 PM »
S12 should be 3 mm os. Careful, this could be a Hernry Ade kit that you can't get rings for.

Jay

Offline crazypj

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Re: S-12 CB500 pistons
« Reply #2 on: March 19, 2006, 08:02:35 PM »
CB500F is only 56mm piston, CB550F is 58.5. You'll have toi be really good at welding to use 500 pistons in a 550
PJ
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Offline MotoRico

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Re: S-12 CB500 pistons
« Reply #3 on: March 19, 2006, 08:07:43 PM »
The kit comes with rings, clips etc?  I was just struck by an epiphany that S12 meant that it was 12 overbores (each of .25mm) so 3mm.

That means they are in effect S2 for a 550.  Correct?

Online bryanj

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Re: S-12 CB500 pistons
« Reply #4 on: March 20, 2006, 09:18:48 AM »
Correct 12 o/s 500 = 2 o/s 550 and if they are one of the usual "rocky" sets they are Art pistons which were original Honda make
Semi Geriatric ex-Honda mechanic and MOT tester (UK version of annual inspection). Garage full of "projects" mostly 500/4 from pre 73 (no road tax in UK).

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Offline Big Jay

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Re: S-12 CB500 pistons
« Reply #5 on: March 20, 2006, 12:10:12 PM »
Correct 12 o/s 500 = 2 o/s 550 and if they are one of the usual "rocky" sets they are Art pistons which were original Honda make

Right, but if it says "HAINDS" in the piston, it does not use standard Honda rings.

Jay