Dual EGT meter, KOSO Digital

This exhaust gas temperature gauge is a neat instrument for setting up your engine and carb. The temperature will be measured and displayed in real-time from two separately mounted sensors, allowing for easy engine set-up. As you probably know, a too-lean mixture burns at a very hot temperature while the exhaust gases of a too-rich mixture don’t reach a certain temperature.
No welding necessary!

In order to achieve optimal engine performance, the spark plug should be brown. Using smaller jets increases performance further but also leads to a white sparkplug and eventually to engine seizure. You have to use a jet which results in a mixture so lean that you get an exhaust gas temperature of 650° on a straight with full throttle. Depending on the material, hotter temperatures are also ok, but you will have to be careful, since overheating can lead to a piston seizure; an integrated warning function can be used. Display readings are between 0 and 1200° C.

Especially useful with 2-cylinder engines!