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Old 04-11-2017, 07:27 AM   #16
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So I am going to have to buy/ find someone with a motor analyzer for me to use.

The difference between 45 deg and 50 deg is SUBSTANTIAL.

I am guessing if it is not over 6 amp it is pretty dang close at 50 deg....

But it was so much faster......
While you're at Thunder, there are several people that can help you with that. I.E. Robert, Carl, Steve, myself and of course, E.A.
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Old 04-11-2017, 08:23 AM   #17
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While you're at Thunder, there are several people that can help you with that. I.E. Robert, Carl, Steve, myself and of course, E.A.
That would be great, thanks for the info. I think I have seen a few around but was not sure.
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Old 04-11-2017, 08:34 AM   #18
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me too
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Old 04-11-2017, 08:51 AM   #19
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You haven't said if it's a 'Torque' or 'Rev' version of the motor!

Did you try leaving the timing down and gearing up instead?
I think this 'set it for 6A' is a bit misleading.
Motors vary, even from the same batch from the same manufacturer. As you add timing you are reducing the efficiency, but what you need to find out is whether this reduction is coming out as a greater increase in heat over power (Power will go up, but as heat etc builds up the motor's internal resistance will also increase)

Don't forget, that as you increase the timing, you also lose torque. It's a balancing act, there is always a trade off somewhere.

At a recent test day (mid size outdoor asphalt) I changed from 13.5 boosted to blinky for some actual races, but forgot to change the motor timing up from 30deg (did change gearing and ESC).
The guy I was with also running Fantom, timing (over 50deg) and we had almost identical gearing. We were 0.18 apart on fastest laps, 0.12 on best 10 laps.
Realising what I'd done (or forgotten to do ) I put timing up to 45deg whilst we both kept the same gearing.
0.14 apart on fastest and 0.05 on best 10 laps.

Sadly I couldn't fit taller gearing without taking everything apart so couldn't be bothered, but it's certainly something I would try before adding a load of heat using timing.

I am not sure I will have to check, but currently I am geared at 3.70 dead on for a 36 x 90 track. It still had really good pull out of the turns with the timing turned up to 50.

I was thinking of dropping a tooth and going up to 50 and see what happens.

Thanks for all the feedback, good stuff here.
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Old 04-11-2017, 09:10 AM   #20
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me too
I would have mentioned you as well, but, you're so infrequent of late.
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Old 04-11-2017, 09:18 AM   #21
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Wow.....
Anyways, I think 6amps is very conservative... Up to 8amps with the highest kv possible(2700+) would be ideal....
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Old 04-11-2017, 09:41 AM   #22
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6 amps for tc 17.5/21.5 chassis and 2 amps for 12th scale?
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Old 04-24-2017, 08:20 PM   #23
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I never had a motor run cool at 6amp draw (17.5 or 21.5 that is). I found in 1/12 tuning is between 2-4.5 amp draw depending on the motor. I ran plenty fast enough in USGT with a new Fantom around 3.5 amps and around 4.0 with the new Actinium V2 perhaps it is because the newer motors are getting more efficient with their power consumption as opposed to older gen ones.
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Old 04-25-2017, 09:42 AM   #24
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My Maclan 25.5 has always drawn 7-8 amps at moderate timing, but come off the track cool, and never faded throughout the entire previous season.

I ultimately look at temps as the final indicator for how far i can advance my timing. If it's coming off the track under 160, then I'm totally happy with the performance.

What's your timing set at, roughly? Recently got myself a maclan 25.5 after falling in love with the viper products (RIP). receipt in the box shows 1.2A @ 47, I bumped it up to the 50 hash, got 2.7A, then to around 55 and saw 5.7A but seemed to get a little warm after a few seconds with no load. Now I am aware A will go up with load, just trying to see if this motor is going to be anywhere near as good as my novak boss vta...
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Old 04-25-2017, 10:02 AM   #25
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did a lot of testing this past weekend with a motor analyzer with my 21.5. Outdoors asphalt in a medium size flowing track , 55degrees timing on a trinity monster, drawing about 6.7 amps geared at a 3.5fdr, was coming off the track at 148degrees. Thats in outdoor track in Florida. No fade whats so ever. just a 2 tenths off the 17.5 times
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Old 04-25-2017, 06:45 PM   #26
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There is really no way of relating timing/gearing to unloaded amp draw.
The only way to get any real correlation is through good'ol trial and error on the track or test pulls on a motor/chassis dyno. Some motors may draw very little current unloaded but draw way too much current with a given timing/gearing combination while others may draw more unloaded amps while being more efficient under load. You have to find the so called "sweet spot" where efficiency and power output become harmonious. The only way to do this effectively is under load. All motors will react differently, even of the same brand or model. The same analogy relates to speakers (electro-mechanical piston). You can take 2 of the same 8ohm (windings) speakers of the same size and depending on enclosure and suspension (load over RPM), they will have completely different impedance (dyno) curves throughout the same frequency/RPM range. But if you connect an ohm meter to their leads they will show the same relative impedance in a static, unloaded state. These are both electro-mechanical motors and have their own performance characteristics under load. One may be more efficient at 45Hz (rpm) and the other more efficient at 38Hz. The load will reveal these efficiencies. Without the load, you are only looking at the static efficiency of the motor vs timing.

That having been said, I'm still using the 6A method and I hate myself. Gotta get that damn dyno finished!
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Old 04-25-2017, 07:17 PM   #27
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did a lot of testing this past weekend with a motor analyzer with my 21.5. Outdoors asphalt in a medium size flowing track , 55degrees timing on a trinity monster, drawing about 6.7 amps geared at a 3.5fdr, was coming off the track at 148degrees. Thats in outdoor track in Florida. No fade whats so ever. just a 2 tenths off the 17.5 times
I would leave the motor right there and play with less F/R toe and add one tooth to the pinion while working on a the car's aero resistance....Good luck....
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Old 04-25-2017, 07:43 PM   #28
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Originally Posted by Marcos.J View Post
did a lot of testing this past weekend with a motor analyzer with my 21.5. Outdoors asphalt in a medium size flowing track , 55degrees timing on a trinity monster, drawing about 6.7 amps geared at a 3.5fdr, was coming off the track at 148degrees. Thats in outdoor track in Florida. No fade whats so ever. just a 2 tenths off the 17.5 times
If anything you're a bit high on the timing, our experience with the Trinity Monster here is they have a very distinct spot where the pitch of the motor is notable, above that they are a bit crackly. It's hard to describe but you know it when you hear it. It's always been between 48 and 51 degrees actual timing on the analyser, with both 13.5 and 21.5 motors.
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Old 04-25-2017, 07:48 PM   #29
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If anything you're a bit high on the timing, our experience with the Trinity Monster here is they have a very distinct spot where the pitch of the motor is notable, above that they are a bit crackly. It's hard to describe but you know it when you hear it. It's always been between 48 and 51 degrees actual timing on the analyser, with both 13.5 and 21.5 motors.
well according to motor temps , timing at the track and about 6 hours of track time in the florida sun motor never went past 148 degrees . i started at 48 degrees and the motor became alive at 55 degrees. motor never faded
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Old 04-25-2017, 10:25 PM   #30
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I think I found the sweet spot for this 21.5..

3.7 fdr at 48

Now just have to work on staying off the curbs.....

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