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soon there won't be anyone left with an undrilled carb, and all the 160 air correctors will end up in retirement homes.
Agreed - seems like "our generation" is evolving the stack to smaller AC, smaller main. For what it's worth - the Bald John was being applied to a tuning that was producing a 62MPH max speed. Many of us are now tuning to cruz at that and above with a max that would be significantly higher.
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Drilling the carb -- why? what posts should I read?
Jack Stack -- I like a good rhyme but sounds more like a late night drunken burger choice. whats up here?
I've also seen some things about raising float height.
Drilling:
Because the carb has reached a limit and can't feed the main jet. Reason - the hole in the bottom of the float chamber has become the limiting passage rather than the hole in the main jet. Meaning - up-jetting is not having its intended effect because the carb cant feed the larger jet. Result - you think you have a larger jet in - but jet is not being fed, is acting like a smaller jet, and motor is being starved.
JackStack - because:
A. Jack has been advising and helping us all jet our carbs - to nice success - and has advised smaller AC than the old favored AC160 that most of us had a comfort level with.
B. If Bald John can have a stack - why not Jack?!
Float height. This is a bit more hit and miss in my view. It's done to:
A. Ensure you don't run the float reservoir dry.
B. Keep the level higher in the jet stack (not JackStack) tube - requiring less pull to feed the jetting.
Lifting this level has been a mixed bag for some of us - personally, I see it as a fix if you have a specific issue - but not a tuning step that needs taking if not.
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My primary curiosity is to get the stock 20/20 and stock 150 jug as optimized as possible and get every possible newton (?) out of the scoot without having too much downtime.
The 20/20 can certainly still be used. A larger carb will have more effect on the top end than putting around town. The article you posted still has merit in my view. For simple plug and play, a performance exhaust and better reeds are probably the quickest and cheapest. This would be accompanied by an up-jetting of your 20/20. If your current jet is around 100? going to a 110 may not require any drilling or modifications. In my view, the tipping point likely gets close when you put a new jug of larger CC on it. Other's can give their opinion.