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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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Hey Chrisi, Great job on Your housing! Really like how You repaired and cleaned up the damage. What bike is that from? I remember You were selling Your Rsr and Stamas, if I remember correctly? You other bike too? Any Pictures? Just curious .
 

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Discussion Starter · #10 ·
There were no damage, I have to weldup some material for the minarelli cylinder. At the moment I make a 2mm spacer for the cylinder and a holder for the head to mount the engine into a minibike.
For sell is at the moment only a Blata elite 11 Chassi and a GRC gp racing.
 

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Discussion Starter · #12 ·
For a testrun I'll put the engine into the GRC RRZ 3. Then is it for sell.
 

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Wow sweet! Should be screaming machine! Hey take video, just want to see that bike and performance. If you can. That is. Good luck Chrisi, wish you the best!
 

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Discussion Starter · #14 ·
Short update!

Get my reed block today it's a tasinarie reed block with 4 carbon reeds.
I have to mille the BZM crankcase to fit it.

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Discussion Starter · #15 ·
UPDATE!!

A few parts are missing馃檮馃檮
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Discussion Starter · #18 ·
It's a stage 6 mk2 racing topend.
Available at stage 6 or you get in contact with me馃榿馃榿
 

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It's a stage 6 mk2 racing topend.
Available at stage 6 or you get in contact with me馃榿馃榿
I was thinking after the pandemic , I will order a couple items from , You like a exhaust pipe and a top end. But, I have to wait for pandemic to finish. But, I thank You for You knowledge and parts lists. HA HA !... Daniel
 
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