OS 9B Carb and OS 3rd. Channel Needle assy. in a Scale

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rctinman

Well-Known Member
Joined
Dec 5, 2003
Messages
1,602
I know that the OS 9B carb is the carb of choice for 1/8th scale, particularly, out West. How many of you are using the OS 3rd. channel needle assy. right on the carb, or do most prefer a 3rd. channel needle separate from the carb?


Thanks in advance!
Steve Ball
 
With the CMB 67, I use the stock carb and a remote needle from Kalistratov that Al Hobbs sells.D5C2B4E6-107C-466C-8CA0-8EBB4AE0703C.jpeg
 
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seperate. I have been using Don Ferette's bases with the OS needle for years. Wouldn't consider throwing a boat out without that set up. One tip is to locate the needle as close to the carb inlet as possible so adjustments come around faster.

I don't beleive there's that many using the 9B's anymore. Either the NR or CMB carb that comes with the motor.

You coming to the scale race Rob?
 
I have not had any issues Steve over the 2 years running this boat. Mounting it directly just removes a leakage path and I believe the concentricity of the needle to the housing is better than a remote block. OS designed the needle for exactly this usage.
 
The only thing you'll see is the O rings in the needle will wear out a little bit sooner due to engine vibration vs. the servo holding the needle setting. The other advantage to a separate needle base is if you swap an engine your settings don't change. I've run both set ups and you'll be fine either way. :cool:
 
The only thing you'll see is the O rings in the needle will wear out a little bit sooner due to engine vibration vs. the servo holding the needle setting. The other advantage to a separate needle base is if you swap an engine your settings don't change. I've run both set ups and you'll be fine either way. :cool:
Thanks Don.

Steve
 
I run mine on the carb on any boat it will fit. I have one 9B remote setup. It’s easier to tune with the needle in the carb my opinion but both ways work great.
 
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