21.5 motor choice, looking for opinions
05-05-2014, 07:56 PM
#91
Turnigy Trackstar 21.5, yeah it's a cheapy at $32-$33 but it's roar legal and it's FAST! First time out with run I set lap and track records for 21.5 and had people checking my car, motor, esc, weight etc to make sure it was legal it was that quick. Plus you can gear it to the moon (very high torque) and if you smoke it, $33 is easier to swallow than $90-$100
05-06-2014, 04:27 AM
#93
Tech Fanatic
2012 NSW Titles
2013 ACT Titles
+various other events
Trinity Revtech 21.5 standard rotor
67-68 rollout (assuming 64mm Tyre diameter)
Full timing on can (the last notch, not as far as the timing will rotate)
as long as you are smooth driver and drivetrain is free this should last you 6 months of club + events but motor will eventually smoke (no real warning) I have fried three so far which is a shame,
Pity that Trinity is no longer making the revtech, hopefully they will release the killshot in 21.5,
2013 ACT Titles
+various other events
Trinity Revtech 21.5 standard rotor
67-68 rollout (assuming 64mm Tyre diameter)
Full timing on can (the last notch, not as far as the timing will rotate)
as long as you are smooth driver and drivetrain is free this should last you 6 months of club + events but motor will eventually smoke (no real warning) I have fried three so far which is a shame,
Pity that Trinity is no longer making the revtech, hopefully they will release the killshot in 21.5,
I have an ORCA, TEKIN Gen2, and KILLSHOT 21.5 motors. Of the 3, I like the Kill Shot (RPM) the best, but I run on large flowing tracks. IF there were shorter tighter tracks the ORCA might be a better choice. The Kill shot and ORCA are the lightest of any brushless motor I have, so if you are trying to hit a weight limit these might be ones to consider. The USGT series I'm running in has a weight limit of 1400 not 1450gr, so the lighter motor is an asset, plus it makes my TCXX chassis perfectly balanced with my race batteries.
05-06-2014, 04:36 AM
#94
Tech Fanatic
I have been running a ShurSpeed 21.5 in my USGT car. I am down to a 3.38 FDR at The Gate with USGT spec tires. Timing is set at 40 and the motor temp after 8 minutes was 127. Track was fast and flowing with 9.5 fast laps and a 9.8 just a couple of laps from the end. That motor has monster torque. I tested it on the Fantom Dyno and the .1 sec rpm was almost 4500 the D3.5 with a high torque rotor only hits 3800 at the same point. For those of you not familiar with the test, the motor is plug started at 5v from zero with a flywheel on the shaft. The Fantom records the rpm and amp draw at .1 second intervals for a little over 2 seconds. Obviously the motor that accelerates the flywheel quicker has more torque. The software does calculate torque, watts output and efficiency. Those are the only two 21.5 motors I have tested.
05-12-2014, 07:35 AM
#95
Tech Fanatic
Ran my kill shot RPM in a race this weekend. Started with the RPM rotor but the track layout had a lot more turns than usual and switched to the HI torque rotor and laps times improved immediately. Changed FDR to around 3.6 and it took off. 3rd qualifier in the mains but got crashed in the first A main and had a handling issue related to the first crash in the second so it was somewhat of a disappointing day, but not because of the kill Shot. Now I have the horsepower to keep up with the fast guys, I just have to do the hard thing: improve my driving.
08-12-2014, 08:01 PM
#97
What would be a good motor to suit a large track with lap times about 22 secs
The straight is about 58 metres straight!
The straight is about 58 metres straight!
Last edited by BJR; 08-12-2014 at 08:59 PM.
08-13-2014, 06:18 PM
#98
Tech Fanatic
At this time the best looking 21.5 motors for a big track on the dyno are the Tekin Gen 2 RPM version, and the R1WURKs. Of the two I've only run the Tekin and after finding a good FDR I really liked that motor. Difficult to do on track comparisons because they change the parking lot track layout each week, but I've been most competive with my bench mark racer (NEED4SPEED) with the ORCA, Kill Shot (RPM) with a 12.5 high torque rotor), and the Tekin RPM. Going to run the R1 this weekend (hopefully) and have a D4 coming for testing.
IF you find a really good 21.5 motor, please me know!
Bottom line is besides the straightaway length, what is the rest of the track like(?), and how long are the mains (we run 12 minute mains in USGT with 21.5 motors) that influence motor selection. The R1 motor is awesome on the dyno but has a very high amp draw compared to other motors I've tested so it may not be ideal for a 12 minute main (but for a 4 or 5 minute race wow!).
Last edited by John Wallace2; 08-13-2014 at 06:33 PM.
08-13-2014, 06:31 PM
#99
Tech Fanatic
I have the Kill Shot 21.5 RPM version motor: one with a 12.5mm rpm rotor and one with the 12.5mm torque rotor. The RPM rotor looks better on the dyno, but on a tighter track the torque rotor gives me better lap times. The biggest advantage the Kill Shots have over the other 21.5 motors I've dyno'd is that they have a very low amp draw, which suggests you can gear them up. While the KS with the Torque stator has a reputation for smoking (particularly when geared very high), so far no such problem for the RPM stator version (for me at least).
08-13-2014, 07:11 PM
#100
Has anyone compared the peak vantage 21.5?
08-13-2014, 07:52 PM
#101
Well, I have been hearing great things about the Team Scream 21.5! Its been screaming past the competition, both on a dyno, and on the track! Stator numbers are much lower than many of the other 21.5 and rotors can range from 1600-1200 or lower if needed I suppose.
08-14-2014, 12:28 AM
#102
Tech Regular
iTrader: (16)
Turnigy Trackstar 21.5, yeah it's a cheapy at $32-$33 but it's roar legal and it's FAST! First time out with run I set lap and track records for 21.5 and had people checking my car, motor, esc, weight etc to make sure it was legal it was that quick. Plus you can gear it to the moon (very high torque) and if you smoke it, $33 is easier to swallow than $90-$100
08-18-2014, 07:02 PM
#104
21.5 f1
Try the Fantom 21.5, I'm completely sold on these motors from Kansas to the gulf coast. Fantom offers several set ups to match your F1 and if your not sure give Jeff a call...
08-23-2014, 10:21 AM
#105
Guys we initally went with the Thunderpower (red case) 21.5 and then we picked up a Killshot (rpm version) 21.5 for our Tamiya mini's ( killshot went in the m03 and the tp went in the m05)
They seem to be evenly matched with the exception that the Killshot seems to run alittle hotter than
The Thunderpower. At a recent race we were talking with a driver that was putting down hotlaps that
Were real fast. He was running the R1 Wurks 21.5 and he had no complaints at all.
They seem to be evenly matched with the exception that the Killshot seems to run alittle hotter than
The Thunderpower. At a recent race we were talking with a driver that was putting down hotlaps that
Were real fast. He was running the R1 Wurks 21.5 and he had no complaints at all.