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Why faster lap times driving my SC10 17.5 than my SC10 3300kv??? >

Why faster lap times driving my SC10 17.5 than my SC10 3300kv???

Why faster lap times driving my SC10 17.5 than my SC10 3300kv???

Old 09-13-2010, 11:02 AM
  #16  
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I have a 4600 system from castle in my RTR Blitz with the Mamba Max Pro. I did have to tune it down a little, put some punch control in and all that, but that thing runs and handles amazingly. Just needs a better driver.

Thing is though I can tell that it is "sensorless" by a tiny amount of cogging, but honestly that hasn't stopped me one bit. A buddy of mine can't tell a difference from when he used to run a sensored tekin system in it. He says it still drives like a dream and he drives it like a dream too. With the the way these motors have moved up lately, I can't tell a difference between 'em now. It's like you have to force them to do it.

Plus it is pretty obvious that I have the HP than most people. We have a triple that's hard to clear and only me and someone else can do it consistently. Everyone else must have a good run or they are in trouble. .
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Old 09-13-2010, 12:40 PM
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Once you're moving there really isn't any difference if you have both systems set up correctly. The only real reason I will never use sensorless for off road racing is for mid-air corrections. If you watch any of the fast guys who drive aggressively, it is common to hit the brakes immediately after coming off a jump to bring the nose down, then punch it to get the nose back up just before landing. This allows you to land squarely on power. Fractions of a second mean the difference between a perfect landing and an epic wipe-out and the small inconsistency in the start time for sensorless doesn't make the cut.
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Old 09-13-2010, 04:14 PM
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Someone from associated wrote that the stock 3300kv sensorless was made to run against stock 17.5 sensored setups without boost. so your boosted 17.5 is faster than the 3300kv. and 3300kv is pretty much a 13.5, but yours is sensorless so its slower than a normal 13.5
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Old 09-13-2010, 04:31 PM
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Besides raw power, what else do you notice? Do you see a difference during entering and exiting a corner? Granted the trucks are setup in the same way, you should notice the difference since torque and rpm characteristic is different... I'm more in the camp of consistency, I believe that only when you have consistency is where you can push your trucks and buggies to do something out of the ordinary to discover whether that made your lap time lower or higher... Fighting your vehicle, as such is the case with mine, makes my lap time higher since even if I did squeeze lower lap time on certain laps, it averages out to be higher...
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Old 09-13-2010, 07:45 PM
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Basically, my 3300kv truck just doesn't/isn't able to get the punch/hook up, out of the corners to clear the jumps that I'm clearing easily with my 17.5. That is, with the current gearing of 16 or 17/87 (can't remember which). So, like the others mentioned, I'll try gearing up to 22 or so (even though it sounds counterintuitive) and see how that goes.
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Old 09-13-2010, 10:09 PM
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Originally Posted by Krio
Once you're moving there really isn't any difference if you have both systems set up correctly. The only real reason I will never use sensorless for off road racing is for mid-air corrections. If you watch any of the fast guys who drive aggressively, it is common to hit the brakes immediately after coming off a jump to bring the nose down, then punch it to get the nose back up just before landing. This allows you to land squarely on power. Fractions of a second mean the difference between a perfect landing and an epic wipe-out and the small inconsistency in the start time for sensorless doesn't make the cut.
Yet it flies absolutely beautiful and with that triple being hard to hit correct sometimes I do have to make mid-air corrections. If I see it might land nose first, I can stab the throttle just fine and tell no difference. Heck at the track that I race at, there is a jump that if you hit wrong just a little bit you must do "panic gas" and hope the nose comes back up. I see absolutely no difference between it in mid air. Everything they can do, my motor can do just as good. Only thing they have that I don't is I can't do dynamic timing. But because I already have a HP advantage in my mind that doesn't bother me. I see no reason for that.
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Old 09-14-2010, 12:04 AM
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Originally Posted by mjk1210
I think it's the sensorless system. The Velineon by Traxxas acts the same way and is hard to race with because of it. You pull the trigger to clear a jump and it doesn't go.
That's why I went with a Tekin in my electric 1/8, and have always used Novaks in my T4. I used to race stadium trucks on a tight carpet track track in the winter where acceleration out of turns was a huge part of laptimes, and in that area the sensored systems were hands down better. It was especially apparent with the SCTs, the throttle control alone is worth the price of the sensored system.
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Old 09-15-2010, 11:11 PM
  #23  
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Well, I geared way taller, I think it was like a 22/84'ish, and the truck ran waaay too hot. Plus they changed the track up, it was hard to compare apples to apples. I ended up going back to a 18/87 and the temps were back under control. The track is more technical now, so the gearing worked well, along with a pretty tight slipper. I just got my new Tekin ESC and 9.5 motor, but haven't had a chance to put it in yet. I still was running faster lap times with my RTR and it's LRP SXX Competition ESC and 17.5 Speed Passion brushless. I'll post more later.
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Old 09-16-2010, 09:31 AM
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Originally Posted by BestNThDez
Well, I geared way taller, I think it was like a 22/84'ish, and the truck ran waaay too hot. Plus they changed the track up, it was hard to compare apples to apples. I ended up going back to a 18/87 and the temps were back under control. The track is more technical now, so the gearing worked well, along with a pretty tight slipper. I just got my new Tekin ESC and 9.5 motor, but haven't had a chance to put it in yet. I still was running faster lap times with my RTR and it's LRP SXX Competition ESC and 17.5 Speed Passion brushless. I'll post more later.


First let me say the track change at 702 to more technical is because they
know I'm going to be back in a couple of weeks LOL" (Havasu Chuck)

As for your RTR 3300 KV motor I think I have your answer. I looked in your
profile & read some of your other posts on other threads to see what you
were doing.

I see you posted that you had your RTR motor over 225F several times.

Heres something alot of people don't realize about brushless motors. Once
you over heat them they appear not to be hurt (but they are) they don't
burn up as easy as brushed motors but they do (loose tourqe)

Once you over heat a brushless motor you start a circle of where your
motor is running hot once. The armature then lost some of it's magnet
strenth (which is tourqe).. Then you get it hot again and it looses more
magnet strenth (more tourqe gone) Then you start another problem" you
now have a weak magnet on the arm so now when you run it, it gets hot
easier and will not pull as much gear as it could new without over heating.

The circle is now off and running wild. So now you are running hotter &
you gear down to cool it. You gear down it runs cooler for a while,then
you gear it up to try to get tourqe back because it won't jump now you
over heat it again & loose more magnet strenth. Then you gear it back
down to cool it off and the tourqe is gone a little more from heat damage
and even with the lower gear your a little hotter then you were the last
time you ran that lower gear.

You go around & around chasing tourqe over heating the magnet &
loosing magnet strenth which is your tourqe. When the magnet gets
weak it now creates more heat. More heat less magnet,less magnet
more heat round & round you go till the motor is total junk...

Most motors like Tekin,Novak & LRP you can put a new rotor back in
with full new magnet strenth and your motor will have all it's tourqe
back. Now you can gear it to it's best performance and it will run cool
again with lots of tourqe.

I've never played with the 3300 RTR motor so I have no idea if you can
replace the rotor. But if AE has a part number for the rotor you can
replace it. Give AE a call & ask if you can replace the rotor, if you can
you will be flying cool and fast once again. If theres no rotors avalible
you need to replace the motor..

Good luck and I hope to meet you at 702 in a couple of weeks"
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Old 09-16-2010, 10:20 AM
  #25  
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IMHO

3000 kv = best for small and tight technical tracks

4000 kv = best for medium tracks

6000 kv = best for big and wide tracks

I think you should compare both trucks on two different size of tracks.
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Old 09-16-2010, 11:03 AM
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I think Chuck nailed it. I ran mine at 22/87 a couple weeks ago on a pretty tight track and it was hot to the touch, but not so hot I that couldn't keep my finger on it for a couple seconds. I've run it the last couple times at 20/87 and that is too low. The motor only got to 135F after running a full 3800 pack.

These motors are pretty cheap. Just get a replacement off $bay or Tower and be done with it.
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Old 09-16-2010, 04:10 PM
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Makes sense. I just finished putting my Tekin motor and ESC in (had them ordered from the first post of this thread. Haven't run them yet, cuz the cord that goes from the ESC to the receiver won't fit into my airtronics receiver. The plug has a small vertical rib on the outside of the plug, which prevents the plug from going into the receiver. It looks like it would fit if the rib were to be ground down. Have any of you ever heard of this. Sucks that I found this out at the very end, the very last plug I went to plug in, after everything was all soldered. What do you know about this?
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Old 09-16-2010, 04:18 PM
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Originally Posted by BestNThDez
Makes sense. I just finished putting my Tekin motor and ESC in (had them ordered from the first post of this thread. Haven't run them yet, cuz the cord that goes from the ESC to the receiver won't fit into my airtronics receiver. The plug has a small vertical rib on the outside of the plug, which prevents the plug from going into the receiver. It looks like it would fit if the rib were to be ground down. Have any of you ever heard of this. Sucks that I found this out at the very end, the very last plug I went to plug in, after everything was all soldered. What do you know about this?
yup just grind or cut it off
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Old 09-16-2010, 04:27 PM
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Originally Posted by Krio
Once you're moving there really isn't any difference if you have both systems set up correctly. The only real reason I will never use sensorless for off road racing is for mid-air corrections. If you watch any of the fast guys who drive aggressively, it is common to hit the brakes immediately after coming off a jump to bring the nose down, then punch it to get the nose back up just before landing. This allows you to land squarely on power. Fractions of a second mean the difference between a perfect landing and an epic wipe-out and the small inconsistency in the start time for sensorless doesn't make the cut.
Thats crazy.. lol you do understand a sensorless motor won't cog in the slightest or have hesitation in the air right.. sensors only prevent cogging at take off, in fact most people run their rx8's in dual mod (sensorless above the slowest RPMS) being sensorless doesn't make the motor hesitate and you don't cog when there isn't any resistance (in the air).. LOL. I beat sensored setups every time I race, even some pro's on a good day. A sensorless vs sensored setup in 1/8 means nothing.. I've used both from a dead stop (on the ground) it is a touch smoother taking off in a direct drive setup ONLY, but if you run a tekno e-clutch or traktion drive you can't feel the difference at all in fact guys w/ sensored system drop their jaw when they go from their tekin and use my mmm tekno setup...

PS even with a clutch on my buggy me and every other nitro guy in the world who races 1/8 buggies manages to be aggressive and control the pitch of our buggies off jumps.

PSPS sorry as neither his comments or mine have anything to do w/ 1/10 2wd vehicles while jumping and I will agree sensored motors are a must for racing 2wd 1/10 iMO as they would get way too squirrley off the line or when getting on the throttle off a tight turn where you had to slow right up. Over jumps or higher RPM's you can't tell the difference even w/ 2wd 1/10s

Last edited by 8ight-e; 09-16-2010 at 04:38 PM.
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Old 09-16-2010, 04:54 PM
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Originally Posted by 8ight-e
Thats crazy.. lol you do understand a sensorless motor won't cog in the slightest or have hesitation in the air right.. sensors only prevent cogging at take off, in fact most people run their rx8's in dual mod (sensorless above the slowest RPMS) being sensorless doesn't make the motor hesitate and you don't cog when there isn't any resistance (in the air).. LOL. I beat sensored setups every time I race, even some pro's on a good day. A sensorless vs sensored setup in 1/8 means nothing.. I've used both from a dead stop (on the ground) it is a touch smoother taking off in a direct drive setup ONLY, but if you run a tekno e-clutch or traktion drive you can't feel the difference at all in fact guys w/ sensored system drop their jaw when they go from their tekin and use my mmm tekno setup...

PS even with a clutch on my buggy me and every other nitro guy in the world who races 1/8 buggies manages to be aggressive and control the pitch of our buggies off jumps.

PSPS sorry as neither his comments or mine have anything to do w/ 1/10 2wd vehicles while jumping and I will agree sensored motors are a must for racing 2wd 1/10 iMO as they would get way too squirrley off the line or when getting on the throttle off a tight turn where you had to slow right up. Over jumps or higher RPM's you can't tell the difference even w/ 2wd 1/10s
lol. I was about to say exactly what your psps you just added said.

However, I still disagree on the "have hesitation in the air". Typical cogging happens when there is a load such that and the start-up algorithm just can't spin the motor up enough to read the back emf and has to re-try, right? The latest and greatest sensorless algorithms now only cog if you are trying to start up from 0 rpm on the face of a jump which is great. I'm not worried about cogging as much as I am the ever so slight hesitation from 0 rpm.
I should have specifically mentioned locking up the tires completely to bring the nose down (which is usually what happens with a 2wd). The start-up algorithm takes a split second to execute, but it isn't a consistent split second. That small variance in can be the difference between bringing the nose up for a smooth landing or lawn darting when flying through the air with the nose of the car well below the rear end to produce more down-force mid flight.
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