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Old 06-28-2011, 10:29 PM   #1
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Default brushed to brushless equivalents

It's been a good couple years since I've done anything RC, so I need to be brought up to speed on the brushed to brushless equivalents.

21.5 = 27T stock?
17.5 = 19T?

etc...
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Old 06-28-2011, 10:43 PM   #2
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Quote:
Originally Posted by Sabin View Post
It's been a good couple years since I've done anything RC, so I need to be brought up to speed on the brushed to brushless equivalents.

21.5 = 27T stock?
17.5 = 19T?

etc...
I know for most touring cars 17.5 has basically replaced 27 turn for "stock" class but it's speed is probably about like a 19 turn if not a bit faster.
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Old 06-28-2011, 11:00 PM   #3
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21.5 is closer to 27T but 21.5 is still quite fast in comparison.

Really, you can't compare brushless to brushed. The brushless motor is way more efficient.
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Old 06-29-2011, 06:01 AM   #4
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I will say my piece and I dont know how other ppl think but brushless had mad a whole new world for rc...... We have in theory a 2 speed to even a three speed gearbox now if you really have a good think....

The electronics are just amazing compared to the days of batteries dumping and brushes gone and being worn out and the com needing to be cut after racing and so on....
Heat is a big factor still but it always will be..... but the amount of thinking involved now is unreal on learning how to push limits in other ways instead of the old days of burning out brushes and flattening a battery cause your over geared...

Can NOT compare brushed to brushless as the nature of the beast are built on different rules.....

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Old 06-29-2011, 03:37 PM   #5
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I think the OP is really asking what would be a good comparison speed wise. All else remaining equal, what would be a similiar speed between the 2.
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Old 06-29-2011, 03:38 PM   #6
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Locally we have a "sportsman" class using 4wd touring cars where we allow Novak 25.5 motors to race against Tamiya 540J Silvercan motors. With 2 cell lipos and rubber tires, the performance of both motors is comparible.

While neither of these two motors are quite as "fast" as 6-cell 27 turn stock, it is a good speed for any level of racer to have fun.
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Old 06-29-2011, 04:49 PM   #7
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In order slowest to fastest.......25.5, sliver can, 21.5, 27t brushed, 17.5, 16.5, 15.5 ....etc.
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Old 06-29-2011, 05:52 PM   #8
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It is common knowledge that a well tuned co27 27t motor is faster than a 17.5t brushless with no esc timing!!! I only run brushed 27t against 17.5 blinky and it really comes down to the driver!!! 19t brushed is also faster than 13.5 brushless with no esc timing, but it's hard to maintain that superiority without constant tuning.......As far as mod, if the track has a short straightaway, a 6t/7t can still compete....
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Old 06-29-2011, 06:41 PM   #9
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no no no. all of you, you're not answering my question at all.

It's this:

"does a 21.5 brushless motor have approximately the same speed as a 27T brushed motor?" "does a 17.5t brushless motor compare to a 19T motor in terms of speed?"

NOT this

Quote:
Really, you can't compare brushless to brushed. The brushless motor is way more efficient.
or this

Quote:
In order slowest to fastest.......25.5, sliver can, 21.5, 27t brushed, 17.5, 16.5, 15.5 ....etc.
or even this

Quote:
I will say my piece and I dont know how other ppl think but brushless had mad a whole new world for rc...... We have in theory a 2 speed to even a three speed gearbox now if you really have a good think....
This post:

Quote:
I think the OP is really asking what would be a good comparison speed wise. All else remaining equal, what would be a similiar speed between the 2.
was the closest thing to what I was asking.

can you guys see how frustrating it is when you ask a simple question and you get a bunch of non-answers?

Now please.. is there anyone here that can answer my question succinctly?
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Old 06-29-2011, 07:02 PM   #10
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Your question cannot be answered as there are too many variables.
As the others have posted, and you don't understand, now that the esc can DIRECTLY affect the speed and power output of a motor, there is no baseline to compare.
Brushless esc's can be zero-timing, in which case there is no additional power, but as soon as you start adding timing, then turbo, it's a different motor.
Also, as the brushless motors are developed, the power is increasing GREATLY. A novak 13.5SS design from 4 yars ago has nearly 50% less power than the latest Ballistic 13.5 designs!
I think a better question to ask is something like "If I want similar power to a 19 turn I used to race back in the day in a touring car, what sort of motor/esc combo's would be comparible". Or something like that.
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Old 06-29-2011, 07:05 PM   #11
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Default Some Reference

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Old 06-29-2011, 08:01 PM   #12
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thank you eComet, that's the information I was looking for.
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Old 06-29-2011, 08:17 PM   #13
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So there is a straight answer.
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Old 06-29-2011, 11:32 PM   #14
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ecomet , I don't know where you got that info , but I am afraid some of it is incorrect!!! There is no way a 25.5=27t ok! To the guy that started the thread, you need to do your homework before you call the priceless info we willingly give you non-answers!!! If you leave this hobby for two months, you will be left behind, let alone two years!!! DO YOUR HOMEWORK!!!!!!!!!!!!!
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Old 06-30-2011, 01:46 AM   #15
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Quote:
Originally Posted by bertrandsv87 View Post
ecomet , I don't know where you got that info , but I am afraid some of it is incorrect!!! There is no way a 25.5=27t ok! To the guy that started the thread, you need to do your homework before you call the priceless info we willingly give you non-answers!!! If you leave this hobby for two months, you will be left behind, let alone two years!!! DO YOUR HOMEWORK!!!!!!!!!!!!!
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Last edited by jjfo80; 06-30-2011 at 08:15 AM.
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