carbs on a lemans mk1

[angler]

since i put the bike back on the road the plugs are burning rich ,i put a colour tune test on the bike and it is showing all blue. is it the petrol [unleaded] against aleaded engine it would be great if any one could help thanks

[Baldini]

I don't know what a colour tune test is. It's not running right & plugs are coked up?

 

I wouldn't think richness would be to do with leaded/unleaded fuel. More likely carb issue (jet sizes, needle & screw settings. Also check that your choke cables/slides aren't sticking & holding choke(s)on. Are both sides the same? Correct/good plugs? Ignition timing OK?

I found the big carbs on LM's do need regular setting up to keep sweet.

 

KB

[pete roper]

It's a 35 year old motorbike. Have the atomisers and needles ever been replaced?

 

Pete

[guzzimeister]

It's a 35 year old motorbike. Have the atomisers and needles ever been replaced?

 

Pete

 

Hi

 

if using a colourtune, flame should be showing blue with a touch of yellow. I would say your'e not far off. Be aware old Le Mans has an accelerator pump in the carb, so you need to have a good long run to check plug colour, as even when warm, blipping from idle will soot the plugs up due to the big gob of fuel that the APs will chuck into the engine.

 

Cheers

 

Guzz