3 replies to this topic

[rusty789]

Basically I believed my mini (Single carb) was running rich as I seem to be using a lot of fuel, Just under 100 miles to a full tank (On a run) And i think its actually doing more miles just pottering around, but surely this should be the other way around? But either way i'm using a lot of fuel (About 25 Mpg)..

So I bought a colour tune kit..

Colourtunes colours are as follows for those who don't know:

Yellow - Rich
Bunsen Blue - Correctly Proportioned
Whitish Blue - Lean

Tested each chamber and got this.. (As you look at the spark plugs)

At Idle..

COLOURS ARE ACCORDING TO MY EYES. (AKA ITS DIFFICULT TO DIFFERENCIATE BUNSEN BLUE AND LIGHT BLUE)



Now it looks to me from what i've seen it looks like i'm running lean or if my eyes are wrong perfect.. so why so much fuel?

[samsfern]

what colour are the plugs after a run

[jaydee]

Lean out mixture a complete turn of the carb nut and see how it goes.
Coulortune spark should show a kind of light blue on tickover then slightly yellow if you rev it, but its better to stick a gas tester in the exhaust and do proper readings.
By the way you're setting mixture for idling and not running, so you have to look at spark plugs after a good run, colortune can be helpful only for the very first setup, and its preety useless when doing final setup.

[minimanclive]

It might be worth doing a compression test too.