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Re: O-tuning Olivier's px200

Posted: Wed Mar 12, 2014 11:03 pm
by fastfrog
case/packer/cylinder porting:

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inlet web slighty flowed (not too much to keep a fine balancing without remove too much matter the other side) and advanced (7° more)

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Re: O-tuning Olivier's px200

Posted: Thu Mar 13, 2014 6:41 pm
by wack 63
What tools are you using to port the cylinder?

Re: O-tuning Olivier's px200

Posted: Thu Mar 13, 2014 7:30 pm
by sean brady scooters
I like the way that you hook under the closing edge of the crank like i often do also ,it can only help cant it by maintaing intake velocity right up to the last moment and also scoop it in :)

Re: O-tuning Olivier's px200

Posted: Fri Mar 14, 2014 11:44 am
by fastfrog
wack 63 wrote:What tools are you using to port the cylinder?
standard carbide cutters, no stone.
sean brady scooters wrote:I like the way that you hook under the closing edge of the crank like i often do also ,it can only help cant it by maintaing intake velocity right up to the last moment and also scoop it in :)
I hooked the inlet back wall too: Hope you can spot it:

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Re: O-tuning Olivier's px200

Posted: Fri Mar 14, 2014 11:41 pm
by GLscoot
Completely way over my head, but I am going to follow this thread and see if I can understand whats going on. Sometimes I wish someone would explain this in diddy proof terms.

Re: O-tuning Olivier's px200

Posted: Fri Mar 14, 2014 11:49 pm
by fastfrog
oups! I'm not clear?

Re: O-tuning Olivier's px200

Posted: Sat Mar 15, 2014 12:19 pm
by Snapper
Great stuff as always,ff! ;)

Re: O-tuning Olivier's px200

Posted: Sat Mar 15, 2014 2:23 pm
by fastfrog
Hi snapper nice to see you on scooterotica too... I've been doin' porn stuff here for a few weeks...

Re: O-tuning Olivier's px200

Posted: Sun Apr 06, 2014 7:17 pm
by fastfrog
crank bitza home.
half motovespa (right "motovespa" web) and italian inlet web. The former one has an insane inlet timing with more than 75° ATDC. Unrideable on open streets...So I swaped the left web for a more common 110/55° and worked it to get 124/55°

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exhaust wider (+1mm each side) and higher( 1,3mm)
before:
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during:
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squish checked 2,38mm!!

Re: O-tuning Olivier's px200

Posted: Mon Apr 07, 2014 3:44 pm
by Jack221
looking good fastfrog, it's going to fly :D
The exhaust port could still do with another 30 minutes work though. The sides of the port should be more parallel yours enter the bore like a trumpet. If you want to keep the oval top then its your choice!