Is rich or lean?

[Felony44]

Today it was 88 and humid i havent flown in weather hotter than 75 i have a OS.50 hyper and today when i would spool up the motor would bobble and sometimes quit all togather right about mid stick while still on the ground ,when it would bobble if i gassed it alittle it would be fine and i would get off the ground and could hover. Im thinking its rich is this right? if so what gets adjusted the idle mixture or the needle? or both?

thanks

[WayneBrown]

yes, it's rich.
Air density changes witt the seasons, cool air is dense, hot air is less dense.
cool means you need to richen, warm/hot you need to lean.
You make a lot more power in the cooler months than summer, so don't get too frisky until you know what to expect power wise from your motor..

[Felony44]

Great thats what i thought it has been running fine before today now do i adjust the idle mixture or needle i would hate to lean it too much by just turning in the needle

[WayneBrown]

main needle first, then fine tune the mid and idle needles.

[BarracudaHockey]

Show me a picture of a mid needle on a hyper :D

You can do quick check of the low end by pinching off the fuel line while its idling and counting. If you die before 3 its too lean. If you havent messed with it its probably a hair rich from the factory in which case it will speed up and die if you hold it for more than 5 or 6 seconds.

What you are looking for is to speed up around 3 or 4 seconds, any more and its probalby too rich. Flight testing will give you your final settings but this will get you pretty close.

[WayneBrown]

Show me a picture of a mid needle on a hyper :D


Thinking of the 60 3 needle carb.. whoops!

You still start with the main needle, and then adjust the idle as a rule, unless the motor simply will not run.
The explaination above works well.

[Felony44]

Ok thanks easy enough.

[Rcer22]

Each engine is a little different. :arggg:
But when you get it right :smokin:
And when it comes back from it's first flight. :OMG
:fly