throttle linkage set-up
12-16-2007, 04:22 PM
#1
Thread Starter
throttle linkage set-up
Whats the best way to set up throttle linkage on OS engines or any engine for that matter. I just guess ,,adjust and hope its right,,most of the time it is,,but sometimes not . My main problem is getting enough trim on my TX to contol the idle setting. Usually the idle trim winds up at the top to get a decent idle,,then it doesnt seem to close far enough to shut the engine down.
Thanks for the help
JIM[sm=71_71.gif]
Thanks for the help
JIM[sm=71_71.gif]
12-16-2007, 06:02 PM
#3
Senior Member
My Feedback: (13)
RE: throttle linkage set-up
If you get the mecahnical set-up correct, then all will be well. Too many folks try to compensate for improper mechanical set-up bu cranking on the endpoints; with predictable results.
So what is proper mechanical set-up? Easy; with the radio throttle stick at half (50%) and the trim lever in the center of its range, you want the servo arm perpendicular (ninety degrees) to the take-off point of the linkage, and the throttle arm exactly midway through its travel range (also perpendicular to the pushrod if at all possible). Ideally, the servo arm and throttle arm are parallel to each other; hard to do, but worth the effort.
This is called "boxing up the throttle linkage", by making a perfect paralleogram. A VERY important aspect is that the throttle arm and servo horn are the same size; i.e., they place the pushrod at the same distance from the center of the movement arc. What this arrangement does is give you a nearly as linear a response as can be had from a rotary output.
Also; start with your ATVs at 100% on both ends, and if you have to change them, do BOTH the same. Different values on either end is what causes binds and spotty response. If you have the geometry right, ATV changes aren't a big deal.
.
So what is proper mechanical set-up? Easy; with the radio throttle stick at half (50%) and the trim lever in the center of its range, you want the servo arm perpendicular (ninety degrees) to the take-off point of the linkage, and the throttle arm exactly midway through its travel range (also perpendicular to the pushrod if at all possible). Ideally, the servo arm and throttle arm are parallel to each other; hard to do, but worth the effort.
This is called "boxing up the throttle linkage", by making a perfect paralleogram. A VERY important aspect is that the throttle arm and servo horn are the same size; i.e., they place the pushrod at the same distance from the center of the movement arc. What this arrangement does is give you a nearly as linear a response as can be had from a rotary output.
Also; start with your ATVs at 100% on both ends, and if you have to change them, do BOTH the same. Different values on either end is what causes binds and spotty response. If you have the geometry right, ATV changes aren't a big deal.
.
