Axial 4.6 BB carb adjustment question
 

I just aquired a Hellfire with a axial 4.6 bb. the carb had the 3rd (midrange) needle. it says never adjust, but the previous owner removed it for cleaning. so, how do i know the setting? axial website doesnt tell where or how to set this except "never touch".

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RE: Axial 4.6 BB carb adjustment question
 

Hi!
It easy!
Just start the engine and set it a little rich! You do this by ear! This is how all experienced fliers set their engines!
Then...throttle down! check that the engine can idle (throttle open apprx 1,5-2mm) ...if not! adjust the low speed needle! Check it by giving full throttle! If the engine hessitates and stops , the low speed (idle needle) is set too lean and must be opened! If it on the other hand the engine bludders and sputters ...then the low speed needle is set too rich and must be turned in some...how much... try and see!

The third needle is the mid range needle and is set so that the mid range rpm is fine when the car is running (under load)!

If you have´nt " engine ear" ...get help from some who is more experienced.

RE: Axial 4.6 BB carb adjustment question
 

[youtube]http://www.youtube.com/watch?v=ma2_CghxiUk&feature=related[/youtube]


Watch that video. It tells you exactly how to tune it, shows you what the engine sounds like under various states of tune, and that guide applies to every car engine on the market with a two needle carb.



I disagree with this. From what I've read it's best to set the midrange needle at the factory default and forget it ever existed. The people who need to fine-tune the midrange with that needle aren't going to be asking other hobbyists how to tune the engine in the first place. Those people are the ones that literally make their living racing RC cars and know more about these engines than you, me and the OP combined.

RE: Axial 4.6 BB carb adjustment question
 

i can tune 2 needle carbs all day, that isnt the issue here, the issue is explained in the first post. forgetting the midrange needle exists isnt an option, its a necessity.
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