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Old 06-15-2010, 11:45 AM   #1
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Default Can I be competitive with a brushed motor?

Can I be competitive with a brushed motor? Will a brushed 27 turn ROAR stock motor be able to keep up with the 17.5 brushless motors?

I will eventually go brushless. I used to race a long time ago and I still have some high end brushed speed controls, so I was going to use brushed motors for a while.
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Old 06-15-2010, 12:05 PM   #2
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Can I be competitive with a brushed motor? Will a brushed 27 turn ROAR stock motor be able to keep up with the 17.5 brushless motors?

I will eventually go brushless. I used to race a long time ago and I still have some high end brushed speed controls, so I was going to use brushed motors for a while.
Yes, in fact sometimes the old brushed motors can be built to be faster, than a comparable BL motor. For example, my 13.5 powered T2 isn't as fast as my Pro 4 with a EPIC Cobalt 27. Even geared very tall, the Pro 4 has a higher top speed. A 17.5 by comparison is pathetically slow, even geared to the moon.

The issue is efficiency. The BL motors SMOKE brushed in efficiency. So despite the fact my brushed car is faster, it slows down after about 6-8 minutes. In that time, my BL car is still going strong. Run time is affected too, but unless your races run longer than 5 minutes, you'll be fine.
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Old 06-15-2010, 12:06 PM   #3
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it could be if it was a well tuned 27t motor & you was runnin it in a class that dont allow timing & boost
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Old 06-15-2010, 12:27 PM   #4
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Cobalt and other rare earth magnets is not allowed in motors that are to be raced in most organisations. (ROAR, EFRA++)

Strange to see cobalt in brushed motors as neodym magnets is stronger than cobalt according to wiki.

Most likely that has to do with temperatures as Cobalt can take highter temperatures than neodym magnets.
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Old 06-15-2010, 12:29 PM   #5
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Yes, in fact sometimes the old brushed motors can be built to be faster, than a comparable BL motor. For example, my 13.5 powered T2 isn't as fast as my Pro 4 with a EPIC Cobalt 27. Even geared very tall, the Pro 4 has a higher top speed. A 17.5 by comparison is pathetically slow, even geared to the moon.
Awesome, Thanks! That will save me some money. I can buy a new 27T ROAR motor and run it with my old speed control. I can use that cash for one of those 2.4GHz radios.
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Old 06-15-2010, 12:33 PM   #6
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I think track size plays into the mix as well... smaller track, 27 turn should be able to hang.

Larger tracks and the turbo/timing boost puts the 27 turn to shame.

One other thing to think about, drag brake seems better on a 27 turn. Sounds weird, but i felt more in control of my Pro4 with a 27 turn compared to a 17.5/GTB combo. Tekin RS seems to have better drag brake than a GTB however.
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Old 06-15-2010, 12:52 PM   #7
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Oops, yea I forgot about the timing boost thing. Nobody around here allows it, so it hasn't become an issue.
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Old 06-15-2010, 12:59 PM   #8
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Originally Posted by FrostyDude View Post
Awesome, Thanks! That will save me some money. I can buy a new 27T ROAR motor and run it with my old speed control. I can use that cash for one of those 2.4GHz radios.
Carefull of the advice you follow here! R40 coulnd't be more wrong about a 27t keeping up with modern ESCs and Brushless 17.5s.
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Old 06-15-2010, 01:09 PM   #9
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Carefull of the advice you follow here! R40 coulnd't be more wrong about a 27t keeping up with modern ESCs and Brushless 17.5s.
Hey Frosty,

If you will be at The Track this weekend make sure you talk to Eric, the owner, he will be able to help you out. Our outdoor program in the summer uses 17.5 open speedo, but in the fall there is a 17.5 controlled speedo class. He has the Speed Passion Citrix combos in stock, which are fairly cheap. There are a lot of guys at The Track that can help you out...so don't hesitate to ask.

-Steve
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Old 06-15-2010, 01:23 PM   #10
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Default brushed motors

Frosty,

What Steve said about the new SP system.
A great deal and you will not have to worry about upgrading in a month -----because you will need/want to go brushless ASAP. Way less work Way less repeted maintenance and always performs exactly the same.

That being said-- if you want a brushed motor stop by this weekend and I will bring one in for you. I as well as most of the rest of the guys have brushed motors sitting around by the "Satchel" full.
In my case I have a "megasatchel" full so you are welcome to one.

The summer schedule is somewhat diofferent than what Eric has posted I believe.But as was stated there is outdoor asphalt this saturday.
The carpet track indoors is always available for practice except for off road nights(which are Friday racing and I am not sure about practice--maybe Wed& Thurs)

So to answer your next question--- yes indoor carpet off road.(with jumps etc)

Anyway welcome back to racing see you at the track.

I am sure Mike or one of the other guys can clarify the schedule--- as well as Eric posted it a few pages ago.

Later,
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Old 06-15-2010, 01:24 PM   #11
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Repeated--- repeated --- repeated


there we go--- 100 times on the board in chalk
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Old 06-15-2010, 02:10 PM   #12
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Our outdoor program in the summer uses 17.5 open speedo, but in the fall there is a 17.5 controlled speedo class.
Does the speed control really have that much of an impact with a 17.5T brushless setup? I thought the 17.5 was supposed to be the brushless equivalent to a 27T ROAR stock motor

I only ask because when I quit racing all the top brushed speed controls had gotten their "on resistance" down so low that there wasn't a big difference between esc's unless you were running a really hot modified motor that could draw a lot of amps.
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Old 06-15-2010, 02:19 PM   #13
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Originally Posted by FrostyDude View Post
Does the speed control really have that much of an impact with a 17.5T brushless setup? I thought the 17.5 was supposed to be the brushless equivalent to a 27T ROAR stock motor

I only ask because when I quit racing all the top brushed speed controls had gotten their "on resistance" down so low that there wasn't a big difference between esc's unless you were running a really hot modified motor that could draw a lot of amps.
OH BOY...well to say it concisely...them days are gone.

But seriously though what you have missed is the new ESC's on the market with dynamic timing. What that has done is make 17.5 as fast as 13.5. Really. So recently ROAR and most ESC manufactures have come up with a "spec" profile or ESC without dynamic timing. This is what is considered "stock". 17.5 open speedo is now "Expert Stock". Don't get too bogged down in all of that just yet. There are literally thousands of post on here debating the ESC issues. Just get back into racing and have some fun. Like I said when your at the track this weekend ask around.
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Old 06-15-2010, 02:51 PM   #14
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what you have missed is the new ESC's on the market with dynamic timing. What that has done is make 17.5 as fast as 13.5. Really. So recently ROAR and most ESC manufactures have come up with a "spec" profile or ESC without dynamic timing. This is what is considered "stock". 17.5 open speedo is now "Expert Stock".
Wow, I had no idea. I had been wondering why there was a "Spec" version offered of certain speed controls.

Is any brand of "Spec" speed control eligible for the controlled class? I have always liked the Novak and Tekin stuff, so I would rather get one of those.
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Old 06-15-2010, 03:02 PM   #15
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on tighter, technical tracks brushed can be very competitive and even faster.
We have seen at national level at the beginning of the year but the downside is it takes more time and $$$ and a selection of motorsto keep in top condition.
Would rather spend that wasted $$$ on a brushless setup that is a lot more consistant and a lot cheaper to run in comparison.
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