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Discussion Starter #1
Hello community

The idea is not new and was also done before from other peoples.
But I've never seen any thread with a small how to and pics.

The idea was how to get more power than a 50cc BZM Engine into a pocket bike. After some research I see that some guys setup a 70cc scooter cylinder on a polini or BZM crankcase. Easyest way is to use a cylinder frome a horizontal Minarelli engine, same stroke only bigger bore 47-47,5mm bore at 39,2mm stroke.

First step is getting the bolt pattern of the minarelli to the BZM crankcase.
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Drilled holes and cutting threads.

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The cylinder I've got is a used stage6 pro race,

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Bolts a Re on the right place, next step will be to fit the cylinder to the crankcase.

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Also want to modify the intake to get a vforce reedblock fitted.

Stay tuned 馃馃徎馃馃徎
 

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You should talk to Jordan Sy about this. He did this same thing on his scooterino.
 

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Discussion Starter #5
This week the crankcase spindled. Spent some time in the workshop today. Welded engine block for the 70cc cylinder. 馃お馃お
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Discussion Starter #6
So, the next steps have been taken. Milled plan and machined housing. Now the cylinder fits onto the BZM housing without any problems.
I processed an old crankshaft and two bearings that I used to test and measure the squish gap. Should set to about 0,7mm at these cylinders. Next steps will be complete the engine and build a mount for the bike to fit in the engine and build an new exhaust manifolder. If add a few pics. 馃榿馃榿锟硷考锟硷考
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