Hi,still pretty much at the bottom of the learning curve and would like feedback on which would be your prefered set up of the two and why?
Cast iron 175
1mm base gasket and no head gasket giving:
160 degrees exhaust.
126 degrees transfer.
132 degrees inlet.
17 degrees blow down.
Piston level with bottom of exhaust port at bdc.
Squish 1.3mm.
Or no base gasket and a 1mm head gasket giving:
156 degrees exhaust.
122 degrees transfer.
136 degrees inlet.
17 degrees blow down.
Piston 1mm overhanging bottom of exhaust port at bdc.
Squish 1.3mm
I'm mainly interested to know what the timing differences will make if any and what peoples thoughts are on running this with a 5.2 final drive,42 mil clubby and 25mil phbl
CHEERS AL
Barrel set up??
- monkey boy
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- sean brady scooters
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preferably the first set up but with vast improvements....
port the barrel to get at least 165 ex,maybe 170 max , but maximize the width firstly in accordance to the quality of piston and rings used..
inlet to be increased to approx 150....and again port done to max width ...
port the barrel to get at least 165 ex,maybe 170 max , but maximize the width firstly in accordance to the quality of piston and rings used..
inlet to be increased to approx 150....and again port done to max width ...

Sean Brady Scooters - 01765 690 698
- monkey boy
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Thanks for the reply Sean!
Obviously some big increases to be made
and loads still to learn
Cheers AL
Obviously some big increases to be made


Cheers AL