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Author Topic: B33 oversized piston  (Read 506 times)

Online Guy Wilson

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B33 oversized piston
« on: 30.07. 2019 13:54 »
BSA B33
I bought a plunger B33 in pieces..most were in gunny sacks... I have a barrel with an 88.4mm diameter but no piston.. Does any one know what oversize piston would fit? Would it be an 88mm ? The bore is good so I was planning to use it as is..
Many thanks
Guy
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Offline RDfella

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Re: B33 oversized piston
« Reply #1 on: 30.07. 2019 16:12 »
That's way past max oversize of .060" (86.5m,  85mm = std). Maybe needs a liner?
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Online Guy Wilson

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Re: B33 oversized piston
« Reply #2 on: 30.07. 2019 16:17 »
thank you, I was just trying to figure out why the bore is so big.. VW beetle pistons fit well on the M and B series engines and go up to 90mm in diameter. It may have had something similar in at one stage...It wasn't in the bottom of the sack though.. I liner might be the way to go..

Guy
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Offline duTch

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Re: B33 oversized piston
« Reply #3 on: 30.07. 2019 21:50 »

 I think I recall someone I knew used a XT Yammie piston in theirs....long time ago *conf2*

 ** Afterthought- maybe it was in a M21
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