Would reducing squish require change in jetting

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Bidsy
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Main scooter: Lambretta S2 Eibar Li150
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Tue Apr 23, 2019 6:03 pm

Had my Granturismo GT200 set up on dyno and jetted but found it could not make top end power. So checked the squish to find it 1.8mm which I now know is too much and needs to be between 1.2mm to 1.5mm so planning on removing the head gasket. the question is if I remove a 0.5mm head gasket to get the squish clearance to 1.3mm would that require any change in jetting. Thanks

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garry inglis
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Main scooter: ts1 230 and rb200
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Tue Apr 23, 2019 6:22 pm

if the carb was ok up to 3\4 throttle on the dyno then i would leave as is and take it easy and do plug checks and up your main say by2 if your running it in as a fresh build you wont hit main jet for a few hundred miles anyway buy then as you ride it you will notice weather its right or not

Bidsy
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Joined: Sun Nov 05, 2017 4:59 pm
Main scooter: Lambretta S2 Eibar Li150
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Tue Apr 23, 2019 6:57 pm

Done 650 miles so far and runs great up 3/4 throttle but no more power after that. Thought it was gearbox to tall so changed to an li150 16x46 made a little difference but not much. Then realised I should of not fitted a head gasket with a 58 / 107 crank, this was after I had it dyno’d, so hoping that bringing the squish down will sort my issue, my concern is I have an 800 mile Europe trip coming up and just like to know if decreasing squish means I need to richen up a bit.

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garry inglis
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Joined: Tue Jul 21, 2015 8:04 pm
ebay user ID: garry52uk
Main scooter: ts1 230 and rb200
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Wed Apr 24, 2019 5:57 pm

A dyno can only get you some were near right plug checks listening for pinking and feeling each throttle position will tell you if your lean

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