Left Cylinder running too lean

after noticing that my left exhaust showed some heavy blue discoloring, i checked my sparkplugs and noticed that the Left one looked like the it was running very lean (whitish color) while the right cylinder too rich (blackish color). The engine runs fine, i dont get any backfires or hickups.

The bike is running a Trispark with a CNW single coil conversion and new 932 Twin Amals.

Since i am not very experienced working with Amals i would like to ask what i should do first ? i am thinking about turning the pilot air in a but to make it richer. would that be the proper way ?

thanks

Only if the air hole/ pilot jet is not blocked in any way :!:

This is one of those questions with 1000 answers.

but the pilot tuning is probably not one of them.

In the first instance using plug colour to investigate tuning is not very good unless doing a proper plug chop.

You say they are new Twin amals. I would dismanatle them and check all the passages are clean and all the settings are identical. Check all the needles, jets, heights etc to make sure they are identical. Its really common for the carbs to come set up differently. Also have very hard look at the inlet tract and ruber mounts to see if there is a leak, crack in rubber boots etc.

Make sure all the settiings are correct for your bike from the Norton workhop manuel. This is a good start.

Go to the Amal site to get a copy of their tuning procedure.

Im not familar with your ignition system but it is always a good idea to check timing is correct. I am a very big believer in Gordon Jennings plug tuning for ignition and jetting.

http://www.strappe.com/plugs.html

Thats a start.

Has anyone ever proved which causes blue pipes. Rich or lean mixtures. I was at a rally2 years ago and asked someone about this. My 750 has a gold hue and the 850 had a blue hue. I was told a rich mixture caused the blue pipes. I have since had reason to believe his may be true as I have done a lot of work on the carbs, and have them running as lean as is reasonable. The blue hue is slowly disappearing. I joined up with a combat owner [ me on the 850 ] and we checked each others fuel use.We did approx. 44 miles, and I used .59 of a gallon [ 2.66 l ] and he used just over a gallon 4.66 l. 74 mpg compared to 44 mpg taking it easy running between 50mph and 65 mph, with a through city ride chuked in. Don't think I HAVE SEEN IT RUN SO FAR, but I usually ride at 65 all the time, on don't follow slow cars. Riding with others you have to take into account safety and staying together.

Over heated headers can come from too rich fuel still burning in the pipes or too lean intense combustion heat, till so rich it dampens down flame or too lean its low on fuel to make heat with. Also too adv or retarded timing can quickly over heat discolor pipes. On the lean cylinder obviously check for air leaks but also that slide cuts outs the same and float levels about right. Slides should be equalized in lift and drop. Can't forget head gasket can leak on one side internally, generally letting oil in chamber so that side gets carboned up more un fuel related. If just a tiny gasket leak might not even see exht smoke. Interesting the mileage differences while still running decently.