Author Topic: cb350 twin pistons  (Read 2078 times)

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Offline KRONUS0100

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cb350 twin pistons
« on: January 07, 2012, 12:51:42 PM »
if i use cb350 twin stock pistons with 350 rings and pins (64mm), what size piston to cylinder wall clearance do i need?  and can i use stock head gasket or do i need the 836 head gasket?  thank you.
MATT
current bikes:  1976 CB750F, 1981 GS1100E
bikes owned:1981 GL1100I, 1990 GS500E, 1981 GS850, 1977 and 1979 GS750, 1974 CB750, 1975 CB750, and a 1982 GS750E

Offline 754

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Re: cb350 twin pistons
« Reply #1 on: January 07, 2012, 01:10:07 PM »
If you use 350 pistons in a 750, you need to recontour ther domes and skirts.... and cut valve pockets
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

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

It's All part of the ADVENTURE...

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

Offline KRONUS0100

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Re: cb350 twin pistons
« Reply #2 on: January 07, 2012, 01:34:50 PM »
hmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm..............i hadnt thought of that
MATT
current bikes:  1976 CB750F, 1981 GS1100E
bikes owned:1981 GL1100I, 1990 GS500E, 1981 GS850, 1977 and 1979 GS750, 1974 CB750, 1975 CB750, and a 1982 GS750E

Offline Jerry Rxman Griffin aka MuthaF'er

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Re: cb350 twin pistons
« Reply #3 on: January 07, 2012, 02:55:59 PM »
That'd give you a 812. You'd need the 812/836 head gasket.
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline 754

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Re: cb350 twin pistons
« Reply #4 on: January 07, 2012, 03:22:09 PM »
 4th over 350 gives 836cc, as lot of early kits were made from them, but there is better stuff out there now..
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

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

It's All part of the ADVENTURE...

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

Offline Big Jay

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Re: cb350 twin pistons
« Reply #5 on: January 07, 2012, 04:45:43 PM »
If you use 350 pistons in a 750, you need to recontour ther domes and skirts.... and cut valve pockets
  And machine the pin bosses wider for the wider 750 rod.

The Wiseco 836 is a direct copy of the 836 we made from CB350 4th over pistons.

Offline Sam Green Racing

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Re: cb350 twin pistons
« Reply #6 on: January 07, 2012, 04:52:57 PM »
Jay was in there at the start, listen to what he says.

Sam ;)
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