G80S bogging down

Information relating to the Matchless G80 or AJS Model 18 500cc Heavyweight.
SPRIDDLER
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Re: G80S bogging down

Post by SPRIDDLER »

markwhitelock wrote:My ‘56 G80 is all back in one piece, I've managed a couple of test rides up the road but it is bogging down around half throttle,
I would also put that down to the possibility of the auto A/R not advancing. An overtight mag chain can cause that.
I've been trying to wind out the mixture screw ever so slightly
Mark, just so that there's no confusion (mine mostly) the choke is 'Off' when the cable is tight.
I assume by 'mixture' screw you are referring to the Pilot screw. It is in fact an air regulating screw and winding it out allows more air to pass to the Pilot jet, weakening the mixture - Item No. 29 in the dia below. This is normally around 1 1/2 turns open (unscrewed from fully in). Anywhere between about 1 and 2 turns unscrewed is normal.

Screw no. 30 is the slow running adjustment by which you adjust the tickover. It merely moves the carb slide up or down as you would when operating the throttle.
Monobloc adjust screws.JPG
:oops: My reply crossed with Mick's.
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Last edited by SPRIDDLER on Mon Jun 29, 2020 7:21 pm, edited 1 time in total.
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clive
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Re: G80S bogging down

Post by clive »

markwhitelock wrote::oops: Whoops. That's a bit embarrassing...

Do it seems the carb may be ok :rofl:
Don't be embarrased think of it as an easy fix!
clive
if it ain't broke don't fix
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