650SS Premier concentrics jetting

Indeed! I've done both film assembly when i was a kid an we were one of the first to get ctp and all the latest workflow and automation was interesting seeing how it all ended up 18k an hour presses pretty crazy now it's all about nanography and inkjet b2 presses.

t ingermanson said:

My bonnie motor pinged pretty bad with 930 carbs, 9:1 pistons, and 190 mains. I went to 220 and it's been good after that. 220s might be generous, but the racket coming off that motor with 190s was something I never wanted to hear again. It's rarely at WOT.

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On my 650 SS with Concentrics, I am starting a complete carb overhaul to address two issues, wont pull above 5,000 revs (generally when overtaking hard it goers flat) and very poor mpg (40ish Imperial mpg at legal speeds).
So I was looking at the Roy Bacon book which suggests 280 mains (might improve the top end as currently 220?), 107 needle jets (currently very worn .106's) and am ready to go down that path, along with new 3 slides and needles.
Also I am running a standard exhaust and air filter.
Any observations from folk who have tried this setup, following on from this thread?