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Old 06-26-2013, 06:44 PM
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can773
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Default RE: Jetti Pro Spin 99

I will disagree, because I have reset controllers to lower timing, and had them fail, and subsequently had the manufacturer tell me that is what caused the failure. It causes some back feeding from the motor to ESC when the timing is incorrect.

If you email Pletty and ask the timing, they will tell you its 24 degrees.

You can play with it if you want, but my experience in doing just what you are suggesting caused equipment failure within two flights of making the change. Not going to get into a technical pee contest, because its pointless, but I have been there, done that, and broke my stuff doing it!


ORIGINAL: gaRCfield

First, sorry to get a little off topic - the Pletty was mentioned above and got me distracted.

I respectfully disagree that timing is a specific setting. If you read the Hacker Q80 manual, the 25deg is a 'recommended' setting ( https://www.aero-model.com/download....-Anleitung.pdf ). Recommended setting for A60 motors is 20-25deg.
It is true that too low of a timing is bad. Basically too low timing advance means the motor isn't pulling hard enough on the magnets to get up to the next winding (like pushing down on a bike pedal before it passes the top). So yes, there is a minimum, but timing is absolutely a tuning mechanism. The RC car guys use it a lot - they balance pinion gearing with timing advance to get good torque and top speed.

I might believe that timing adjustment is limited on a 28 pole motor, still have to work through that scenario. I do agree that there is a limit to the range of adjustment, but there is a range.

From Castle's website:
What you’ll find when you experiment with timing advance settings, is that going up or down from the normal setting will cause two reactions. With each step down from normal, your motor temp will go down and the top speed will go down about the same as dropping a tooth on the pinion. Going up, it’s just the opposite – it’s like adding a pinion tooth, but the motor temp will go up ...
Higher advance makes the motor run hotter, and the higher the Kv of the motor, the hotter it will get! Too high of an advance setting will give the same results as too much advance on a brushed motor – you will actually LOSE power and speed while the motor cooks itself!
Hacker ESC settings:
Auto: 7-30 deg
Soft: 7deg (2-pole motors)
Hard: 22-30deg (multi-pole motors)