polini longstroke ?

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ducksta
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Can you longstroke a polini 177 kit if so what crank and what packer plate is required
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Ginch
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You can put a long stroke crank on nearly anything. If you mean a 60mm (not 62) crank then you normally need 1.5mm of packing to bring it back to "normal". Or there's this head that means you don't need a packer, and it's a way better design - especially in the squish department.

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http://www.sip-scootershop.com/en/produ ... +_38348600
ducksta
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so malossi head fits the polini ok
looking at a polini barral with a better piston 60mm maz crank 1.5 packer 24/24 carb (modified) sip exhaust 22 tooth cosa clutch
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Ginch
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ducksta wrote:so malossi head fits the polini ok
looking at a polini barral with a better piston 60mm maz crank 1.5 packer 24/24 carb (modified) sip exhaust 22 tooth cosa clutch
Well it's the same stud pattern on the cylinder so yes the Malossi head fits... but this one has been re-machined to ensure the squish band is a good match to the piston crown shape and that the combustion chamber cc's are correct. As you can imagine the head volume at (say) 10:1 on a 166 will make for too high compression on a 187.

If you want to use a packer then don't use that head, use the 57mm version. You're going to run a Grand Sport piston then?
ducksta
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Yes grand sport piston , will go with the head makes sense i just need a kit putting together by a supplier so i dont have 2 pistons and heads anybody do this might send sip a email
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Ginch
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Let's know how that works out, I haven't had much luck with them in the past splitting up kits... got a few standard kit heads kicking around here!
OzOAP
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I put a 60mm P2 crank in my Malossi 166. Now 175cc
3mm longer stroke and 5mm longer rod. Used a 1/4ins pack plate (6.35mm).
Used it for a few years as a mile eater rally going machine, engine is currently in my scootercrosser.
Ginch
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OzOAP wrote:I put a 60mm P2 crank in my Malossi 166. Now 175cc
3mm longer stroke and 5mm longer rod. Used a 1/4ins pack plate (6.35mm).
Used it for a few years as a mile eater rally going machine, engine is currently in my scootercrosser.
Did the case need machining to fit it? Or did you take the lip off the crank?
OzOAP
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Can do either way, but I machined casing so I could run wider inlet port.
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