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Old 07-31-2009, 12:22 PM   #1
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Default Brushless for Johnson 540

I would like to know if there is a brushless motor which is approved to replace the Johnson 540 Silvercan brushed motor for racing.
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Old 07-31-2009, 12:48 PM   #2
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I would like to know if there is a brushless motor which is approved to replace the Johnson 540 Silvercan brushed motor for racing.

I think 17.5 is the replacement or the silvercan Mabuchi
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Old 07-31-2009, 01:01 PM   #3
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Quote:
Originally Posted by howard1 View Post
I would like to know if there is a brushless motor which is approved to replace the Johnson 540 Silvercan brushed motor for racing.
I guess this news(the top) could satisfied you.
But i don't believe it could replace silver can.
The problem of cans is durability, since allowance of brushless then silver can have no chance to compare.
I think the race org. should change the silver can class to 17.5 or 21.5 something, this is what i think.
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Old 07-31-2009, 01:12 PM   #4
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I think 17.5 is the replacement or the silvercan Mabuchi
In terms of rpm per volt (or kV), the no-timing-advance 17.5 is pretty close to a 540. So it works OK in a class with limited gear ratios (like Tamiya spec classes).

But the 17.5 generates a lot more power and can pull a much bigger gear than a 540. Add in the new generation ESCs that crank the timing and you have the potential to go a lot quicker.

Short answer is that we will never find equivalency between brushed and brushless motors. We just need to find sensible classes to replace brushed.

Brushless technology appears to have matured now, I don't think there is a huge amount of performance left to be extracted from the motors and ESCs. It seems that 17.5 is a good 27T stock replacement.

I actually think there is more of a need now to keep 540 racing alive, purely from a cost basis. A complete, competitive brushless setup is very expensive. A usable 540 setup comes with almost every Tamiya kit - you get a whole car thrown in too for half the price!
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Old 07-31-2009, 01:20 PM   #5
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21.5 will be the likely/smart replacement for 540 classes.

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Old 02-17-2010, 05:32 PM   #6
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so is the replacement be 21.5 or 25.5
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Old 02-17-2010, 06:37 PM   #7
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The new 25.5 Novak motor would be as close as possible to a silver can. I believe the motor was designed as the next generation upgrade for silver can class racing. Of course, the ESC is an important part of the equation. With BL becoming the norm in rc, the cost of brushed esc's will make the cost comparison impossible. A BL system will be more expensive to purchase but if you look at things in longer terms, the extended cost of the BL becomes more relevant.
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Old 02-17-2010, 06:49 PM   #8
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You would have to look at the output Kv of both motors.
21.5=1800 Kv
25.5=1550 Kv
Then times by battery output volt to get Rpms. Both motors would be close. 21.5 would be close to a "Tuned" Silver Can and the 25.5 would out of the box Silver Can. The speedos would have to be Spec with no Boost/Turbo function. Looks like there will be some new Speedo's coming out with no Profiles adjustments but will have brake adjustments.
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Old 02-17-2010, 07:02 PM   #9
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Well it is much more than just RPMs which is why some say we will never have a true equivalency between brushed and BL. The 25.5 may be the same in RPMs or very near to a silver can but it has much more torque so can utilize a higher gear ratio and be faster. Even if you limit the gear ratios the BL will have a slight acceleration advantage. That said we tested and ran the Hobbywing system with the black can Tamiya motors in our mini class and were pretty happy with the results.
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Old 02-17-2010, 07:52 PM   #10
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they have allowed 21.5 brushless in our 540 class now, and it is day and night comparison.

the 25.5 however might be the best substitute.
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Old 02-17-2010, 10:29 PM   #11
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Quote:
Originally Posted by howard1 View Post
I would like to know if there is a brushless motor which is approved to replace the Johnson 540 Silvercan brushed motor for racing.
Depends who you ask to approve it.

Clubs have their own ideas, whereas international bodies have their own completely different ideas again, so it's a mishmash of sorts because all of the reasons listed by previous posters. If you just want to know what BL motor you can run at your club, they would be then the place to ask. if you want to know what you can run in a certain competition, you need to study their regulations.

As explained before it is very difficult to compare the two. We switched to 21.5 and it was just unfair to the silvercans (or even the black cans which we also allowed in the class). Limiting gearing options might help even things out but still, as explained above, the torque of BL is going to be an advantage.

That being the situation, it looks like there are two schools of thought. One that argues that silvercan should be kept (or that it will never go away because of the cost advantage) and another which argues there are already cheap options with BL systems like the EZrun, etc. These are however not that cheap to buy upfront, but in the long run might come cheaper if you factor in the cost of replacing silvercans over say a year. There is of course a crossover point. If your racing timetable is not that busy, you may find you only go through a couple of silvercans a season, so BL is still the expensive option. If you have a really busy racing timetable, you might find the BL cheaper than having to buy five silvercans or more a year.

There are also the outliers, i.e. people who would do anything to be faster, money no object, and go out and buy specially prepared silvercans but I think this is a hobby gone mad and it only fuels the argument that we should get rid of silvercans because it implicitly means these people are cheating. Practically, it is difficult to argue it is cheating, but still, most people think it is going overboard and not in tune with the spirit of the silvercan class.

There are also various types of silvercan (Mabucchi, Johnson, etc) and there are people who claim some are better than others, but that again is missing the point of spec racing. It may be however the reason why in the end people will just decide toi give it up altogether.
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Old 02-18-2010, 10:34 AM   #12
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We have designed an overall program in participation with USVTA for cost controlled racing. Our most affordable, sensored system is 129.99. We believe that this is an attractive package and program because, it not only includes these customized products, but also features our Trade-In programs and the availability of service parts and accessories.

Other companies may feature a product at a low purchase price; but those companies do not offer the after-sale customer support and service programs that we maintain for Novak customers.

TeamNovak USVTA Program Update
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Old 02-18-2010, 10:42 AM   #13
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It is no longer "which motor is equal the speed of 540J" question anymore in 2009....SPEEDO will make a 21.5 motor fly like a rocket....

To really get a good replacement BL motor = 540J kinda speed....club need to specify 1 specific speedo with no timing adjustment with 1 specify motor turns with no timing adjustment as well....otherwise, you will never find a good solution for that.

So far...Speed Passion and Novak both have speedo/motor that are not adjustable...however, Novak SS motor might still be able to adjust some timing. SP were all locked and cannot be advance.
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Old 02-18-2010, 10:50 AM   #14
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Quote:
Originally Posted by Solara View Post
It is no longer "which motor is equal the speed of 540J" question anymore in 2009....SPEEDO will make a 21.5 motor fly like a rocket....

To really get a good replacement BL motor = 540J kinda speed....club need to specify 1 specific speedo with no timing adjustment with 1 specify motor turns with no timing adjustment as well....otherwise, you will never find a good solution for that.

So far...Speed Passion and Novak both have speedo/motor that are not adjustable...however, Novak SS motor might still be able to adjust some timing. SP were all locked and cannot be advance.
We will be offering certain SS Pro Spec motor with fixed timing. Our original SS Pros had no timing advance option---I think they were glued, or epoxied. Then we discontinued the adhesive to offer limited timing adjustments. We are tooling a special ring that cannot be adjusted.

The extremely limited timing range of our current SS Pros are not much of an issue when used with controllers with no timing advance options--such as our Havoc 2S.
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Old 02-18-2010, 11:43 AM   #15
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We will be offering certain SS Pro Spec motor with fixed timing. Our original SS Pros had no timing advance option---I think they were glued, or epoxied. Then we discontinued the adhesive to offer limited timing adjustments. We are tooling a special ring that cannot be adjusted.

The extremely limited timing range of our current SS Pros are not much of an issue when used with controllers with no timing advance options--such as our Havoc 2S.
Good to know that NOVAK issued this as a solution. That way Novak would have a full line of really SPEC system for those CLASSES that would like to do spec.
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