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amal concentic on a MAC

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  • amal concentic on a MAC

    almost given up on solving richness on the original 276 amal carb. I do have a 26mm concentric in OK shape. does anybody have starting points for jetting etc?

  • #2
    Try the factory guys .... .... they are usually pretty good at nailing down at least a starting point. Good luck.
    Or try Ed Gilkison .... [email protected] ..... be prepared to wait .... Ed does NOT rush to respond !

    An update .... I found some info. in a folder that came with my project Venom.... this info. is from an old " Fishtail " contributor , the carb is a 26mm Concentric, fitted to a Viper, carb. no R 626. .... Main jet 220 ... Pilot jet 622/107 ..... Needle jet 106 ( 622/122 ) , ..... Valve cutaway #3 ... Needle position 2 .
    This info was given to the Fishtail subscriber by Amal Ltd.

    I am VERY new to Velocette machines so not really up on models .... hope that this helps you.
    Last edited by LImeyrider; 12-19-2019, 08:02 PM.


    • #3
      And obviously whether you'll be running with an air filter will make a difference. My guess is that 220mj would be for no air filter, and probably the Viper would be using the M17/8 cam, unlike your 'softer' MAC cam. Is your motor standard in terms of cam and compression ratio Rob?
      Last edited by joolstacho; 12-19-2019, 10:38 PM.


      • #4
        Mac still has M17/5 cam and 3/8 Rad followers , comp. ratio estimated at 7.5 :1( .030 off barrel) early head with the smaller inlet valve, mouth of port has been opened up to 1 1/16 by previous caretaker. No air filter of course.
        So a lot softer than a viper. I think I will start at 180 and go from there . -13 Deg here today so might have to wait a few months before trying it!