240LikesMotiv RC
02-13-2019, 04:00 PM - Wikipost
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10-12-2016, 09:30 PM
#316
Generally I play with the motor timing on the dyno and find the sweet spot for power, then check the timing and amp draw to be sure it's okay. However, the number you have are not unreasonable and do look a bit low in comparison. I can't wait to hear how it does on track.
10-12-2016, 09:32 PM
#317
Generally I play with the motor timing on the dyno and find the sweet spot for power, then check the timing and amp draw to be sure it's okay. However, the number you have are not unreasonable and do look a bit low in comparison. I can't wait to hear how it does on track.
10-13-2016, 12:31 PM
#321
Tech Adept
iTrader: (5)
That all said you can see on the test bench the M Code 21.5 is less powerful than the Fantom FR-1 and Trinity 24K but still above the LRP X20 21.5. These are all motors shimmed properly and set to the timing "sweet spot" as the above post. My next step is to put the motor in the car and compare my lap times.
But at the moment for the 21.5 I don't see it being as fast.
But at the moment for the 21.5 I don't see it being as fast.
10-13-2016, 03:46 PM
#322
That all said you can see on the test bench the M Code 21.5 is less powerful than the Fantom FR-1 and Trinity 24K but still above the LRP X20 21.5. These are all motors shimmed properly and set to the timing "sweet spot" as the above post. My next step is to put the motor in the car and compare my lap times.
But at the moment for the 21.5 I don't see it being as fast.
But at the moment for the 21.5 I don't see it being as fast.
I don't think you can gear both motors the same to get a comparison Each motor is different.
This is my theory. On the bench, the motor that produces more KV or RPM will have a greater top speed. Max efficiency is around 6amps. You will notice that a motor that has a high torque rotor will always draw less amps and less RPM than a motor that uses a mid torque motor. A mild torque motor will produce the most RPM and amps under no load.
For example, If you swap to the optional super high torque rotor in your 24k trinity, it will pull about 2 to 2.5 amps and have a few hundred Ks less at no load. All these bench test are deceiving sometimes. Sure a flywheel can help give you somewhat of a bench mark but you can't alter the gearing of a flywheel or create progressive resistance as you can with gearing. A 24k may have enough torque to spin your flywheel just as easily as the motiv. You might need a bigger or heavier one to really see the difference under heavier loads. Actual track testing would be best.
I don't have a S-MID Motiv, I have a S-High which will produce under 2.3A at 48 timing, whereas the 24k with 49 timing has more KV (RPM) and pulls approx 6.3A. If I was to compare - I would calculate the 24k motors top RPM (KV) and rollout vs the other motors top RPM (KV) to obtain an accurate rollout and gearing for the reduction of KV but higher torque. (see chart)
This way, both motor will have the same top speed, and this is where you can tell which motor is stronger. From my testing the motiv was stronger in the low to mid range. While the trinity pulled a little harder mid to top, but was laggy on the bottom compared to the motiv. If the track was very technical, the motiv would gain a little bit out of every exit of the turn. Lowering the timing on the trinity to 40-43 degrees and altering the FDR to compensate, the trinity had a bit better punch in the technical sections and didn't lose by as much per lap.
(example) - These are not actual KV numbers - I used these numbers to demonstrate the calculation points.
Trinity Motiv
21.5 21..5
Motor KV 1900 1700
2S Lipo volts 8 8
IntDrv (Xray) 1.9 1.9
Pinon 42 45
Spur 96 92
FDR 4.34 3.88
Tire Dia (mm) 63 63
Rollout 45.57 50.95
No Load rpm 15,200 13,600
No Load kph 41.56 41.58
Attached is a video of my Car (yellow and blue) using a motiv vs Fantom in (Green and Black Car)
https://www.facebook.com/rc404/videos/1654109548212580/
Last edited by Dino_D; 10-13-2016 at 04:04 PM.
10-13-2016, 05:25 PM
#323
I appreciate all the attempts to justify the Motive, and yes track time shall be the ultimate test but the more I look at it the worse it seems, you simply can't make a silk purse from a sow's ear. Emails to Motive, unanswered. It's just not looking good!
10-13-2016, 06:55 PM
#324
Tech Addict
iTrader: (38)
On my last race I experimented using a Trinity Torquoise 12.5 rotor and the motor changed for the better. I also geared the car at 3.16 FDR with 35 degrees of timing. The car improved on the straight while running relatively warm (168-175 degrees average). There was no fading on power and I did not loose a lot of torque either. This motor likes to be geared low. At the end, the motor helped me secure the 4th place overall in the Summer Series at LHR. I guess is a keeper, lol. The high torque rotor is a must, at least on my particular track.
10-13-2016, 09:40 PM
#325
On my last race I experimented using a Trinity Torquoise 12.5 rotor and the motor changed for the better. I also geared the car at 3.16 FDR with 35 degrees of timing. The car improved on the straight while running relatively warm (168-175 degrees average). There was no fading on power and I did not loose a lot of torque either. This motor likes to be geared low. At the end, the motor helped me secure the 4th place overall in the Summer Series at LHR. I guess is a keeper, lol. The high torque rotor is a must, at least on my particular track.
I do think the S-High rotor would have been better but I simply don't have one to try. I'm not sure I would have been able to gear up more but it may have picked up a little. Glad to hear that you're finding your way with that motor.
10-14-2016, 12:41 AM
#326
Thanks for finding out the info much appreciated. It seems strange considering the Mid is recommended for 1/12 and Zen racing are primarily a 1/12 distributor. We don't race on the black carpet so from your comments I struggle to see why the High rotor is the only one to choose. Hmmmm
12th car I again left the timing and on a decent club size technical track it felt better with a lower rollout but still cold.
A bit lost now with what to do.
10-14-2016, 05:09 AM
#328
Tech Adept
Where did you get to regarding rollout and timing? I've been swapping mine between LMP and GT12 and in the gt car last night I went 2 laps quicker with 66mm v 72mm rollout. The motor was not hot with either at 45 degrees timing. The fantom guys were at 66 and 24k at 72.
12th car I again left the timing and on a decent club size technical track it felt better with a lower rollout but still cold.
A bit lost now with what to do.
12th car I again left the timing and on a decent club size technical track it felt better with a lower rollout but still cold.
A bit lost now with what to do.
10-14-2016, 06:24 AM
#330
It's sitting on the shelf as I've been doing really well with my previous motor a 24K. When I used it also on a medium technical track I was in the 60s rollout. The motor felt really smooth on power, probably too smooth and it didn't feel as punchy or as fast as my 24K. Running about 72 on the 24K. I should try it again with a higher rollout and see what happens.
