240LikesMotiv RC
02-13-2019, 04:00 PM - Wikipost
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10-12-2016, 06:37 AM
#301
I always find it funny (at my local tracks). The guys that complain about motor number and constantly buy motors of the week are the same guys that are laps off the pace.
They can tell you how many Kv, rpm, rotor strength and deviation of the sensor board for every motor they have. Will spend hours tinkering with shimming a motor to get 1 More Kv or 100 more rpm. But ask them what Shock oil, piston, droop, camber, caster or ride height they are running and they have no clue. They have not been thru their car in weeks have shock with no oil, bearings that are seized and then complain about motor temps or lack of speed.
More time on the chassis will yield more gain on the track than you will ever gain from a spec motor on a dyno.
Just some food for thought
10-12-2016, 06:59 AM
#302
I've found that the builders who belittle dynos the most perform the worst on them. Once you have your car set up and are competitive, you look for gains in your motors. Given my last main event I lapped the field in the last race, I don't question my car's set up but look to gain on the motor side.
10-12-2016, 07:01 AM
#303
Any ideas on gearing for an M Code 21.5 in a touring car? As a guide I am running FDR of 2.78 with a Fantom FR-1 set at 48 degrees actual timing in an Awesomatix A800. In my A700 I run a FDR of 2.85 using either the FR-1 or a Trinity 24K 21.5 with actual timing of 46 degrees. (Timing is as per my motorlyzer). Motors come off around 60c after a run I have been running my 13.5 in the A800 at a FDR of 4 but the motor was coming off at around 40c without a fan.
The fantom normally has more torque than the 24k, thus you will always have a slightly lower FDR with a fantom. Also the 24k is more of an RPM motor, hence good on large tracks. The Motiv has way more torque than either of those 2 motors, hence you probably have to gear lower to get the speed out of it when running the S-MID version. If you are already running 2.78, perhaps try 2.6.
Timing wise between 47-49 with a S-MID
The S-HIGH will have way more torque and not enough RPM compared to the S-MID and not the best application of that rotor on a big track.
10-12-2016, 07:43 AM
#304
Yeah it's smid set the timing to around 49-50 for 4.2a seemed to drop off after that
will re dyno now I've reset the timing and post (kids asleep now) top sensor screw was stripped out of the box so had to deemed it to loosen it up so I could change timing wasn't impressed with that but all sorted now
will re dyno now I've reset the timing and post (kids asleep now) top sensor screw was stripped out of the box so had to deemed it to loosen it up so I could change timing wasn't impressed with that but all sorted now
10-12-2016, 07:44 AM
#305
what timing are those motors at?
in 17.5 I found the motiv similar to the 24k in performance.
my 24k had more power at the start with fading at the end, with a friends motiv running more consistent throughout the run and more power at the end - that's dependent on timing and gearing of course.
For 21.5 I liked the motiv around 52* on the can, I'd gear it up. 40c is too cold for it to be going fast. No 21.5 24k to compare with at the time.
in 17.5 I found the motiv similar to the 24k in performance.
my 24k had more power at the start with fading at the end, with a friends motiv running more consistent throughout the run and more power at the end - that's dependent on timing and gearing of course.
For 21.5 I liked the motiv around 52* on the can, I'd gear it up. 40c is too cold for it to be going fast. No 21.5 24k to compare with at the time.
We run on smaller tight track up here mainly with 60ft straights.
The motiv with S-HIGH is ideal on tight tracks, and I found that if the track is a bit more open I would run, FDR 3.9 with 49 timing, and if the track has more slow speed corners, I bring the timing down to 40 and a 3.8 FDR. The lower timing increases more mid range power even though you lowered the FDR. Motor temps are in the 140-150 range with fan
10-12-2016, 08:09 AM
#306
Yeah it's smid set the timing to around 49-50 for 4.2a seemed to drop off after that
will re dyno now I've reset the timing and post (kids asleep now) top sensor screw was stripped out of the box so had to deemed it to loosen it up so I could change timing wasn't impressed with that but all sorted now
will re dyno now I've reset the timing and post (kids asleep now) top sensor screw was stripped out of the box so had to deemed it to loosen it up so I could change timing wasn't impressed with that but all sorted now
I can give you an example. Most of my 24k have a gauss rating of 1525, and my cert 1552. My motiv has 1648 with the S-HIGH. The higher the gauss the more torque the rotor has. The rating on the stator matters too, but just taking the rotor as a quick comparison.
But on the track, the motiv has way more mid range, thus you can use a way lower FDR with the more acceleration and same top speed.
Here is an idea. Best way is to calculate the roll out with FDR and max rpm of the 24k and then use to figure out what FDR you need based on the RPM of the motiv. Then let us know how is the acceleration of the motiv vs the 24k.
10-12-2016, 10:30 AM
#308
I don't own a 21.5 of any kind but I've played with plenty of 17.5's and 13.5's from Motiv and others. I've found it best to evaluate each motors power curve as I set it up looking for the best area under the curve. Not specifically looking for RPM, current draw, KV, etc.. Doing so the Motiv motors I've used generally do draw a bit less current than some others mfg motors, and have a lower KV than those motors. But, on the track the Motiv's are just as fast as others and generally have very little fade and run at a good temp.
Generally at the end of a competitive run inside these motors are 150-160°f. During the summer we run on a large outdoor track. Normally I run mod outside but on the rare occasion I've had to run 17.5 the temp will creep up to 180-185° but the motor still runs very strong. And, that temp is common with all brands of 17.5's at this track.
Also, I'm just not a fan of equalizing current draw to compare motors. I want to see the best performance out of each motor and if that happens at different current draws then so be it. I often see people suggest that 6.0a is the sweet spot for a 17.5 motor and I'll agree that it's not a bad setting but it's not a one-size-fits-all kinda deal.
Now, if you don't have a motor checker or any other tools (clearly nexxus, you do) I would take a Motiv right out of the box, set the endbell at 48° and go have fun with it. All of the Motiv's I've checked with the stock S-Mid rotor work very well at that setting and don't fade at the end, when geared well (see wiki).
Bottom line for me is that the track tells the full story but setting the motor to what looks to be it's sweet spot before hitting the track helps you narrow down where you need to be with very little guesswork at the track.
Generally at the end of a competitive run inside these motors are 150-160°f. During the summer we run on a large outdoor track. Normally I run mod outside but on the rare occasion I've had to run 17.5 the temp will creep up to 180-185° but the motor still runs very strong. And, that temp is common with all brands of 17.5's at this track.
Also, I'm just not a fan of equalizing current draw to compare motors. I want to see the best performance out of each motor and if that happens at different current draws then so be it. I often see people suggest that 6.0a is the sweet spot for a 17.5 motor and I'll agree that it's not a bad setting but it's not a one-size-fits-all kinda deal.
Now, if you don't have a motor checker or any other tools (clearly nexxus, you do) I would take a Motiv right out of the box, set the endbell at 48° and go have fun with it. All of the Motiv's I've checked with the stock S-Mid rotor work very well at that setting and don't fade at the end, when geared well (see wiki).
Bottom line for me is that the track tells the full story but setting the motor to what looks to be it's sweet spot before hitting the track helps you narrow down where you need to be with very little guesswork at the track.
10-12-2016, 02:05 PM
#311
Agreed. High for sure.
10-12-2016, 03:24 PM
#312
I say question everything, specially those heavy duty steel drivetrain parts that increase the rotational mass too much for stock racing... Ideally you want a full carbon fiber drivetrain or close in weight to consider the car's potential achieved for stock, but all I see is just more mod ready tc chassis being produced that bog down the stock 17.5t motors too much, and then racers have to upgrade to lighter parts to be competitive.... Cheers....
I've found that the builders who belittle dynos the most perform the worst on them. Once you have your car set up and are competitive, you look for gains in your motors. Given my last main event I lapped the field in the last race, I don't question my car's set up but look to gain on the motor side.
10-12-2016, 06:07 PM
#313
I don't own a 21.5 of any kind but I've played with plenty of 17.5's and 13.5's from Motiv and others. I've found it best to evaluate each motors power curve as I set it up looking for the best area under the curve. Not specifically looking for RPM, current draw, KV, etc.. Doing so the Motiv motors I've used generally do draw a bit less current than some others mfg motors, and have a lower KV than those motors. But, on the track the Motiv's are just as fast as others and generally have very little fade and run at a good temp.
Generally at the end of a competitive run inside these motors are 150-160°f. During the summer we run on a large outdoor track. Normally I run mod outside but on the rare occasion I've had to run 17.5 the temp will creep up to 180-185° but the motor still runs very strong. And, that temp is common with all brands of 17.5's at this track.
Also, I'm just not a fan of equalizing current draw to compare motors. I want to see the best performance out of each motor and if that happens at different current draws then so be it. I often see people suggest that 6.0a is the sweet spot for a 17.5 motor and I'll agree that it's not a bad setting but it's not a one-size-fits-all kinda deal.
Now, if you don't have a motor checker or any other tools (clearly nexxus, you do) I would take a Motiv right out of the box, set the endbell at 48° and go have fun with it. All of the Motiv's I've checked with the stock S-Mid rotor work very well at that setting and don't fade at the end, when geared well (see wiki).
Bottom line for me is that the track tells the full story but setting the motor to what looks to be it's sweet spot before hitting the track helps you narrow down where you need to be with very little guesswork at the track.
Generally at the end of a competitive run inside these motors are 150-160°f. During the summer we run on a large outdoor track. Normally I run mod outside but on the rare occasion I've had to run 17.5 the temp will creep up to 180-185° but the motor still runs very strong. And, that temp is common with all brands of 17.5's at this track.
Also, I'm just not a fan of equalizing current draw to compare motors. I want to see the best performance out of each motor and if that happens at different current draws then so be it. I often see people suggest that 6.0a is the sweet spot for a 17.5 motor and I'll agree that it's not a bad setting but it's not a one-size-fits-all kinda deal.
Now, if you don't have a motor checker or any other tools (clearly nexxus, you do) I would take a Motiv right out of the box, set the endbell at 48° and go have fun with it. All of the Motiv's I've checked with the stock S-Mid rotor work very well at that setting and don't fade at the end, when geared well (see wiki).
Bottom line for me is that the track tells the full story but setting the motor to what looks to be it's sweet spot before hitting the track helps you narrow down where you need to be with very little guesswork at the track.
For the M Code 21.5 this is what I had
2431 kv 3.7A
2477kv 3.9A
2612kv 4.8A
2581kv 4.6A
2502kv 4.0A
So for me the optimal timing was the last figure, 30 extra kv was worth 0.1A, to get another 80kv would be 0.6A so the efficiency is dropping off significantly. At that figure it read an "Actual" motor timing of 49 degrees which is also consistent with the Wiki post on these motors.
10-12-2016, 06:17 PM
#314
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.
10-12-2016, 06:24 PM
#315
Compare it to the 13.5 which is very much on par with the FR-1 and 24K equivalent winds. Once again, same criteria used. After timing set then dyno'd
It was based on this I figured the 21.5 was worth the punt, but so far it's not promising (should have seen that when I had to dremel out the stripped sensor board screw on a new motor lol)
It was based on this I figured the 21.5 was worth the punt, but so far it's not promising (should have seen that when I had to dremel out the stripped sensor board screw on a new motor lol)