Author Topic: piston confusion, which kind?  (Read 1781 times)

Online Rocket Racer

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Re: piston confusion, which kind?
« Reply #30 on: 04.08. 2015 22:59 »
early genuine pistons had a diagonal slot on one side of the skirt to allow for piston expansion without seizure. It allowed for tighter piston clearances. You wont find a modern repro piston with those. I cannot remember off the cuff if that slot fitted forwards or backwards, none of mine are slotted, but they are referred to in the books.
A good rider periodically checks all nuts and bolts with a spanner to see that they are tight - Instruction Manual for BSA B series, p46, para 2.
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Online muskrat

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Re: piston confusion, which kind?
« Reply #31 on: 05.08. 2015 12:13 »
Those split skirt pistons were the first set I put in the plunger 30 odd years ago. They lasted well. Only a thou and a half clearance.
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Online RichardL

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Re: piston confusion, which kind?
« Reply #32 on: 05.08. 2015 13:00 »
Oh boy! One piston.
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Online cyclobutch

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Re: piston confusion, which kind?
« Reply #33 on: 06.08. 2015 12:33 »
Found mine had one split type and one not when I first pulled it down.
Various, including ...
'58 Iron Head Flash Bitza