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Concentric on a Comet


Well Known and Active Forum Website User
VOC Member
I'm thinking of fitting a Mk 1 concentric onto my Comet to replace the very leaky 289 on it at the moment.I came across an article on Thevincent.com site that suggests drilling out the idle jet to 0.040 thou and also cutting away the brass fuel feed nozzle.Is there anyone out there that has done this successfully? I'd hate to ruin a new carb.cheersDave

Bill Thomas

Well Known and Active Forum Website User
VOC Member
Greetings, As Howard said, Vin's are not the same, He has done the tube mod' and likes it, But i have gone back to uncut on one carb and just picked up another tube to do the other. When It was first on the Forum I said to Bernard, I didn't know I had a problem !! If it's a NEW carb the drilling should Not be needed, It was only the early ones that were like that. Cheers Bill.

Chris Launders

Well Known and Active Forum Website User
VOC Member
Hi Dave.
See my thread "unable to get reliable tickover" a couple of weeks ago,my twin needed the restrictors drilling out but my comet is ok without.The best way would be to fit the carb unmodified and see how it goes.
Cheers Chris.
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