Here are 2 different postings I found by doing a Google search on "kyosho gx12 settings". I make no claims for the spelling, punctuations or grammar, I'm not a proof reader.
#1
"I have this engine too. Really big piece of $h!t, anyway...this engine is very easy to tune. It has just 1 needle. That thing which is like a screw if you notice. Screw it untill it stops. Then, unscrew it 3 turns. Then, you will notice that if you go full throttle, the car barely can move. You would have to screw it a bit 1/8 of a turn and notice the difference in performance. Do that untill you are satisfied. If you overdid it, then unscrew it a little. My setup is 2 full turns exactly from fully close position".
#2
How tune your GX12 Engine for high performance
Yeah, it might bo only a .12 engine, but if tuned propely, it can pack a punch. If tuned right i will increase top speed and accelleration. It this article I will show you how to tune an Kyosho GX12 engine properly.
1. Run in your engine. The engine must be properly run in before you try anything like this. There will be an article on how to do this later, but this step is vital.
2.Start your engine. This may sound ovious, but I am suprized at the amount of people who do it without the engine running.
3. Turn the Fuel/air mix clockwise an 1/8th of a turn at a time. This will let an fraction of air in at an time. Turning it 1/8th of a turn also means that you can find the best performance settings for your car, and write them down.
4. Next, set the idle speed ajuster.
5.Make sure at full revs, you get blue smoke coming out of the exaust. If you dont, then you may have not got your settings right.
You then have sucessfully tuned an GX12 engine!