Author Topic: Need a new piston?  (Read 1739 times)

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Offline dperl

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Need a new piston?
« on: August 04, 2016, 01:22:18 PM »
Anyone know where to source one for '77 A? Will '77 K work?

Offline 05c50

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Re: Need a new piston?
« Reply #1 on: August 04, 2016, 03:37:42 PM »
My 77A is running piston's from a 77K. When I bought it, the cylinders were rusted and the pistons were seized. The pistons are working fine.

.......Paul
Wear a helmet,the life you save may be your own.Ask me how I know.               CB650C,CB550F,GL1000,CB750A

Offline stikman

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Re: Need a new piston?
« Reply #2 on: October 12, 2016, 02:17:56 PM »
You can replace all the A pistons with K pistons, but not just one.  The compression ratio is apparently higher on the stock K pistons compared to the A pistons and replacing just one A piston with a K piston will likely throw your engine out of balance.  Sorry for the late reply.
1977 CB750A "High Horse": 836cc, mild porting, custom cam, K5 roundtops, v-stacks...
1973 CB750K D5 plunger frame chopper currently building..

Offline 754

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Re: Need a new piston?
« Reply #3 on: October 12, 2016, 02:53:35 PM »
Get a k piston and mill the top...
Maker of the WELDLESS 750 Frame Kit
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Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

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73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way