Running lean?

[jabcrosshook]

Go on then, I'll look stupid, what does running lean mean?

[Stu]

low fuel to air ratio

[Stu]

ok i will explain more

if you remove your air filter and run the bike it will be lean as there is more air going in and not the right amount of fuel to match it

[Guest]

Also known as running weak.

[nigelwood1]

Or frey bentos.....

[rollazuki]

Also prone to making the end of spark plugs melt off, eating the top of pistons, and nibbling little chunks out of valves. ALL BAD STUFF!!!

A light metallic 'pinking' noise is usually the prelude to running weak problems, as is an overheated spark plug, or higher than expected piston/head temps(also exhaust header)

Very bad state of affairs generally!!

[jabcrosshook]

I see I see, thank you all very much.

[slugworth1987]

ok in relation to this: what are the issues of runing to rich?

Edited November 20, 2008 by slugworth1987

[Guest]

over fueling ... causes loss of immedeate power until it clears ( like running on half choke etc )

[slugworth1987]

no long term effects to the engine? i know the spark looses life but apart from that... does it involve damage to the valves and head also?

[jamesw]

when running overly rich you can also encounter what is known as bore washing which is where the excess fuel strips the oil from the cylinder walls which as you can imagine is not particularly good.

[Stu]

when running overly rich you can also encounter what is known as bore washing which is where the excess fuel strips the oil from the cylinder walls which as you can imagine is not particularly good.

 

and it can run down the barrel into the sump as found on early the TLs

[jamesw]

when running overly rich you can also encounter what is known as bore washing which is where the excess fuel strips the oil from the cylinder walls which as you can imagine is not particularly good.

 

and it can run down the barrel into the sump as found on early the TLs