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John Lindsay
29-07-2009, 09:02 AM
Morning All,

Having a wee problem.

Last night after assembling my new Mi4 I installed the radio gear. The instructions state that the servo horn must be perpendicular (at 90 degrees) to the chassis. When the servo is powered up and comes to centre though there is not a suitable spline to allow this to happen. It's got to be just before or just after 90.

So I've fitted it in the slightly back position, and adjusted the sub trim 74 clicks to the left, on my Futaba 3VCs transmitter to bring the servo horn perpendicular with the chassis, and centre the steering assembly within the car.

My problem is this. I've tried 2 different KO 2143 servo's in my car, both have the same problem. My brother's car which has the exact same setup went together with no problems like this at all. Both radios had a model reset performed on them, and I've tried swapping servo horns between his car and mine and the problem is still in my car.

When I put the servo horn on the opposite way it sits perfectly perpendicular to the servo case, but obviously in this way it wouldn't work as the servo can only face one way in the car.

I also tried disassembling one of the servos to see if I could rotate the spline drive gear by a tooth but this doesn't seem possible, (however I could be wrong)

Does anyone have any ideas what could be causing this problem? Or is it not worth bothering about? The sub-trim adjustment I have made will be fine?

Any help would be greatly appreciated, and if I've missed out any info then please just ask for clarification.

Regards,


John Lindsay

John_s
29-07-2009, 09:26 AM
Just make sure your left and right travel is correct when you trim the car to go straight because the trim will affect your dual rates. So just do youer turning circles after its all ready

John Lindsay
29-07-2009, 09:31 AM
Cheers John Boy, see you Sunday?



John

fairweather_man
29-07-2009, 10:30 AM
The KO spline has an odd number of teeth (either 23 or 25), so a perpendicular horn on one side will always be offset on the other.

Nothing to be concerned about, using the sub-trim is the correct adjustment.