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Best 17.5 Motor for 2WD Buggy and 1/10 Truck

Best 17.5 Motor for 2WD Buggy and 1/10 Truck

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Old 04-06-2010, 10:02 AM
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Originally Posted by 2wdMod View Post
Kris, I totally agree on Tekins aproach being the most ethical.It's been nice to be able to just plug in the hot wire and in a couple minutes have the most current firmware on the esc. BUT I also agree with some others.This is already getting WAY out of hand AGAIN. I think the correct aproach is to limit the timing capabilities of the speedo for stock classes.I beleive this for 1 reason.Look how fast stock has become in the last year with a 17.5.NOBODY thought the speeds we are getting out of a "stock" motor were possible 2 years ago when ROAR made BL legal for stock classes. Well even if we switch to 21.5 power, how long do you think it will take for the timing and boost to make a 21.5 stock class just as fast or even faster than the class was when we first started running BL 17.5's in stock? The solution isnt to spec another motor it's to limit speed control timing and take the adjustable timing off the motor.It's stock. It has ALWAYS been a class with fixed timing rules to help keep things in check until BL power and for some reason ROAR left the timing specs as open as can be.At the time I beleive it was to make sure the BL set-ups could compete with the brushed stockers that were being run at the time.Well here we sit 2 years later and a brushed stocker cant hold a candle to a 17.5 system with a timing advance speedo.So Now it's time to reel it back in, and since in other forms of racing they seem to have no quams about putting limitations on equipment for the good of the class, I think the most reasonable solution would be to follow that format to help get things back under control.
It is definitely out of hand since the stock class is supposed to be relatively inexpensive to be *close* to the guys who go all out. I was just saying that under the current rules no one is in the wrong. Stock definitely needs to be reeled in.

Originally Posted by K_King View Post
Tekin and the Firewire is definitely a good thing, however isnt it somewhat limited by the tech inside the actual ESC itself?
Realistically there are only so many things you can do to make a brushless motor faster. The biggest is obviously timing and the tekin has the hardware to monitor rpm, current, and time delay which is more than you need to decide what timing to run. It has enough processing power to do all that and more so processing power won't be an issue for a long time. The only other real way to increase power is to lower the internal resistance (the RS pro already has 48 fets giving it the lowest on resistance of any esc) or have FETs with shorter switching times. The RS already has the top of the line fets, so it will be a long time before that happens and in the grand scheme of things a car with shorter wires to the motor rivals the effects of a more efficient fet.
Technically, there is a limit to the internals on the RS. Realistically, it will be 5 years before it matters.
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Old 04-09-2010, 08:43 PM
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has anyone ever tried the Speed Passion 17.5t brushless system for spec slash racing?

http://www.amainhobbies.com/product_...r-Combo-3000KV

thanks in advance
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Old 04-09-2010, 11:24 PM
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Originally Posted by K_King View Post
Tekin and the Firewire is definitely a good thing, however isnt it somewhat limited by the tech inside the actual ESC itself?
In the case of the Mamba Max Pro, (likely the Tekin RS Pro as well) the processor in the ESC has more than enough speed and calculating ability to add quite a few more features that may be able to add a bit more power as well as increase efficiency when you are not at full power. I have started using a data logger to dial in my MMPro to max out my crappy Losi 13.5 motor for Super Stock. I sat CRAPPY because Matt Murph running a non dynamic timing GTB ESC and his 17.5 motor ran away from this 13.5 every time I ran near him. The Mamba Max Pro has a very cool feature they aptly named "CHEAT" for Castle High Energy Advanced Timing. What makes this such a great thing is that it increases the timing as a function of RPM. You choose where it will start, get a few choices for where it will end, and how many degrees it will add over the span. Unlike just cranking the end bell, this runs modest timing at low rpm, making the motor far more efficient down low. It runs cooler and actually has more torque while sucking less battery. Then as the revs climb, it dials up the timing to maintain the torque to a higher speed, and can even push the top speed up a bit. Right now the CHEAT feature is very limited, it only has the one linear slope over just a few rpm range choices. A software update could give many more choices and multiple slopes or even let you draw a curve like they do for the throttle and brakes. My 13.5 is rated as a 175 watt motor by Losi, I see over 400 watts at the exit of slow corners, and it pulls over 200 watts all the way to the end fo the straight, hitting 30 mph now. On the Losi ESC it would have weak acceleration and thermal if I geared it over 26 mph. It does run fairly hot, but nothing like what it would do trying to make this power on fixed timing.

Trying to police and rule on timing is now gone. Since it is all software, even if someone came up with a dyno/timing light setup to check them at the race, it would not be too hard for sneaky people to dial in a setup where the advance kics in from 1 minute into the main, until the 5 min mark, then reverts back the the legal timing for the post race tech. It could be so well hidden in the code, noone will ever figure it out.
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Old 04-09-2010, 11:30 PM
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Ahh yeah Matt, Im glad I run his motors
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Old 04-09-2010, 11:32 PM
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Originally Posted by GSMnow View Post
In the case of the Mamba Max Pro, (likely the Tekin RS Pro as well) the processor in the ESC has more than enough speed and calculating ability to add quite a few more features that may be able to add a bit more power as well as increase efficiency when you are not at full power. I have started using a data logger to dial in my MMPro to max out my crappy Losi 13.5 motor for Super Stock. I sat CRAPPY because Matt Murph running a non dynamic timing GTB ESC and his 17.5 motor ran away from this 13.5 every time I ran near him. The Mamba Max Pro has a very cool feature they aptly named "CHEAT" for Castle High Energy Advanced Timing. What makes this such a great thing is that it increases the timing as a function of RPM. You choose where it will start, get a few choices for where it will end, and how many degrees it will add over the span. Unlike just cranking the end bell, this runs modest timing at low rpm, making the motor far more efficient down low. It runs cooler and actually has more torque while sucking less battery. Then as the revs climb, it dials up the timing to maintain the torque to a higher speed, and can even push the top speed up a bit. Right now the CHEAT feature is very limited, it only has the one linear slope over just a few rpm range choices. A software update could give many more choices and multiple slopes or even let you draw a curve like they do for the throttle and brakes. My 13.5 is rated as a 175 watt motor by Losi, I see over 400 watts at the exit of slow corners, and it pulls over 200 watts all the way to the end fo the straight, hitting 30 mph now. On the Losi ESC it would have weak acceleration and thermal if I geared it over 26 mph. It does run fairly hot, but nothing like what it would do trying to make this power on fixed timing.

Trying to police and rule on timing is now gone. Since it is all software, even if someone came up with a dyno/timing light setup to check them at the race, it would not be too hard for sneaky people to dial in a setup where the advance kics in from 1 minute into the main, until the 5 min mark, then reverts back the the legal timing for the post race tech. It could be so well hidden in the code, noone will ever figure it out.
Well they could by saying only locked coded ESCs were legal. That would mean a 17.5 motor with X speed control to power it. I mean right now its out of hand really. 17.5 can run 13.5+ speeds, so its no longer a STOCK class. Its a getting a timing ESC and a 17.5 and watch it fly class.
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Old 04-10-2010, 01:31 AM
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I don't think it's fair you say 17.5 is like 13.5 cuz if u run a top esc with a 13.5 it will be quicker again.

Remember when brushless came in we all ran 13.5 against brushed and then they slowed it down to 17.5. Since then lipo has come in with extra voltage which has to take some of the blame for the speed increase. A lot people run 5000mah packs in 2wd 17.5 class only uses 900-1000 mah a race so your voltage sits very high on the big packs. This is responsible for the high speeds.

I think tuning the esc is good aspect of racing. Since you really dont work on the brushless motors like the old brushed ones and you don't have to solder and care for cells anymore. Not much to do in the pits now.
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Old 04-10-2010, 07:56 AM
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Originally Posted by Tom87 View Post
I don't think it's fair you say 17.5 is like 13.5 cuz if u run a top esc with a 13.5 it will be quicker again.

Remember when brushless came in we all ran 13.5 against brushed and then they slowed it down to 17.5. Since then lipo has come in with extra voltage which has to take some of the blame for the speed increase. A lot people run 5000mah packs in 2wd 17.5 class only uses 900-1000 mah a race so your voltage sits very high on the big packs. This is responsible for the high speeds.

I think tuning the esc is good aspect of racing. Since you really dont work on the brushless motors like the old brushed ones and you don't have to solder and care for cells anymore. Not much to do in the pits now.

Can you run a 13.5 in a stock class? No, so being able to run a 17.5 motor that runs like a 13.5 is unfair.

Actually we ran 10.5s against 19t which was a joke really. 10.5 blew 19ts away. Thats why they slowed it down. Brushed motors had less punch, less speed over a run and less top end for the most part. Tuning is fine, I agree, but not for a STOCK class. Save it for all of the other classes.
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Old 04-10-2010, 09:13 AM
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Originally Posted by K_King View Post
Can you run a 13.5 in a stock class? No, so being able to run a 17.5 motor that runs like a 13.5 is unfair.

Actually we ran 10.5s against 19t which was a joke really. 10.5 blew 19ts away. Thats why they slowed it down. Brushed motors had less punch, less speed over a run and less top end for the most part. Tuning is fine, I agree, but not for a STOCK class. Save it for all of the other classes.
I agree I used to run stock until the esc's you need to "keep up" cost so much more. You can get a 6.5 Novak havok for mod set up for less than JUST the cost of the top of the line stock esc's
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Old 04-10-2010, 02:15 PM
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All the wild timing features on the new ESC's are not too much help on hotter motors. A 13.5 and maybe a 10.5 will make more power with the dymanic timing and such, but once you are up there on power, it is really limited more by grip than torque. 17.5 is really pretty doggy unless you have timing cranked in, and 13.5 with a great ESC is just getting to where you have to modulate the power. 10.5 is pretty fast with just fixed moderate timing. The dynamic timing could give a bit more top end while reducing heat and maybe give a longer run time with better low rpm efficiency. Going to a motor any hotter than this and you can easilly have more power and torque than the tires can put down without wild timing, so there is little benefit from the dynamic timing. On my 13.5, the castle CHEAT mode is waking it up nicely, but it is still a dog of a motor compared to many I have seen. I will still try a bit more advance to push the revs higher, so hopefully I can run a smaller pinion to get more punch and keep motor heat about the same. There really is only one place on the current layout where I need to high speed, so doing it with a lot of dynamic timing just may be the hot ticket.

The Novak Ballistic 13.5 is rated for 2200 KV unloaded. Using the CHEAT mode, my Losi 13.5, rated at 2360 KV is revving over 21,000 rpm under load at 7.6 volts. Almost 2770 KV under the load of pushing the car to 30 mph. Without CHEAT, using fixed timing, I could not get the car over 26 mph without serious heat issues.

Back to the original thread...
Has anyone run the Hacker E40 17.5 stock legal motor??

A-Main Hobbies has them listed at a great price.
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Old 04-10-2010, 02:18 PM
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http://www.youtube.com/watch?v=psUz0P5KeDk

I did a small non-scientific test of how the profiles help speed. Mainly you can tell the difference in punch, which is easiest, but also higher RPM you can hear the motor has a different pitch.
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Old 04-11-2010, 06:08 AM
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Thumbs up nice video

the video says it all....that set-up is really fast. how do you guys feel about roar making two classes at nats, mod or 17.5(no sponsors)
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Old 04-11-2010, 07:40 AM
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most big races and even club tracks race 13.5 in stock. makes it easy for folks to move up to mod and even run mod if not enuff stocks show up. no gearing issues either. shocker, most places and races dont follow the previous version of rules that MEOW came up with. now they release this joker. gonna attempt to put offroad thru the same ringer than put major holes in the onroad camp.

R
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Old 07-21-2010, 10:21 AM
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Originally Posted by not home View Post
say no to novak, those ballistics are garbage. original trinity duo, or the epic nemesis motor.
I keep hearing people thrash Novak Products, and it is total bull I have used Castle,LRP,Tekin,SpeedPassion,even Traxxas stuff and Novak esc's and motors are still around where alot of the so called Greatest, Best, most Awesome,ect,ect are sidelined. So remember when you are looking for the *Best* out there, opinions are just that! Opinions
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Old 11-18-2010, 09:35 AM
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ROAR sportsman stock esc approvals. end of esc war discussion. period.



as for motors, tekin and lrp are the only ones i have experience with. have no real complaints about either. both have good speed, the lrp's seem to be punchier, as they should- they use higher quality magnets. how do i know that you ask. i have a magnameter for testing magnets used in assembly line robotics. magnets get fatigued and have to be tested so the corresponding electromagnets voltage can be adjusted.
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Old 11-18-2010, 09:45 AM
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I run Orion v3 17.5.......awesome motors.
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