Misc: Carburettors Poor Running Comet Problem

[Mark N]

Thanks for the update; I also don’t get a lot of time due to shift work, etc.
My first action was to change the plug cap for a non resistor type, but clasping at straws…

 

[greg brillus]

looking at the earlier pics of the carby parts........I'm refering to the Needle and needle jets.......these are different in length from the 276 verses the 289 carby's........Also another trick that could be causing fuel starvation low down, the lowermost gasket that seals the bottom large cap nut to the base of the carb body and jet block........If this gasket has the wrong ID then this effectively blocks off the entire pilot circuit making the carby impossible to tune..........I would look closely at these items as well as the float items, and the float fuel height in particular........this can be discussed once you have had time to look at these items........good luck with it.........Cheers.

 

[Bradley Burt]

Mark N and Cannop,

What have you both done to cure this problem? I have a similar carburettor issue. Not electrical in this case.

Thanks,
Brad.

 

[Mark N]

I’ve not touched the bikes since the autumn, but will be checking the carb as per Greg’s reply, but I’m not even sure my issue is carb related; it may be ignition.

 

[Cannop]

Hi Brad, short of replacing the carb I ran out of options unfortunately. Due to a hectic life right now I don't have a lot of spare time to dedicate to the garage and all the projects I have in there, so I've shipped the Comet off to Cosmo in St Leonards on Sea to give it a good going over and basically recommission it as it's only done 4,600 miles since its restoration 30 years ago.

I want to be out and about riding it in any free time I have, not problem solving, hence the decision to farm the work out! I'll report back what the issue was once Cosmo's sorted it out.