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Old 09-15-2010, 11:03 AM   #1426
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Ok thanks Granpa.. I have been mainly using my motors with hi amps thinking they were better (using them in TC not mini).. I will give the motors with a lower amp reading a go... there are a heap of them in my draw as I thought they were not as good as my motors with higher amp readings.

One thing I notice with the motors that have a higher amp reading is they drop off allot faster then the motors with a lower amp pull.. but they do seem faster for the 1st half of the race..

Question when you run in your motors is that what you aim for.. a lower amp draw? I am a bit of a novice with 540's.. but if the motor is clean would stronger magnets mean higher amps? Or can't you tell if a motor has good magnets this way?

My 4 hole motor which has allot of top end not much torque and has an amp reading of 1.2 @ 7.2.. thats kinda why I thought hi amp more torque.

Thanks..
It's pretty much what A-Ko said. Amp draw equals heat, but is really not much of a factor in a stock motor. Using the right gearing is IMO critical in a TC or a F1. The mentality of "if the car ain't fast, throw in a bigger pinion" ruins more motors than anything else. If your car is dropping performance in the last half of the race, assuming 5 minute heats, you're running too tall a gear. Try dropping a tooth or two on your pinion, and check your lap times. Sometimes, what seems fast isn't. Driver feel is notoriously inaccurate. Lap times win races. How fast you "feel" our car is means diddly squat. Sorry, just a pet peeve of mine.

Nah, when running in or water dipping a motor, all I'm trying to do is get the brushes seated. Sometimes do them backwards and other times forwards. Doesn't seem to make a helluva lot of difference. Please don't get me wrong, I am not saying that some of the exotic combinations don't work. What I'm saying is after a few runs on that motor you won't see a significant difference. So if you're dunking your motor in cow piss, rinsing it out with horse urine, and lubing with bull droppings, it's okay if it works for you. Still think that most of that stuff is "mental".

Good luck with your motor work. For me, it developed into a hobby within a hobby.
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Old 09-15-2010, 11:42 AM   #1427
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Using the right gearing is IMO critical in a TC or a F1. The mentality of "if the car ain't fast, throw in a bigger pinion" ruins more motors than anything else. If your car is dropping performance in the last half of the race, assuming 5 minute heats, you're running too tall a gear. Try dropping a tooth or two on your pinion, and check your lap times. Sometimes, what seems fast isn't. Driver feel is notoriously inaccurate. Lap times win races. How fast you "feel" our car is means diddly squat. Sorry, just a pet peeve of mine.
This is very true. You will often see guys, especially in F1, who come out of the gate blazing, but by 3 minutes in, the motor is blazing and they are back markers. One tooth can be a big difference.

OTOH, if you have throttle discipline, and can avoid full throttle in the infield, a bigger pinion is a way to get more from the motor. You just cannot be WFO all over the track and expect the motor to live.
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Old 09-15-2010, 09:33 PM   #1428
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My LWB Mini is pretty good and suits my driving to a T. Too bad that a good driver didn't have it cause there is easily .5 seconds and as much as 1 sec in there over my driving. It was in cruise mode all weekend cause I'm not good enough to consistently drive the tight lines. Had Brandon K and Micheal Monaghan test it and Bk thought it was "really good" and MM told me "it's perfect. Don't change anything". Any time you come out, you're welcome to drive anything I've got. Also have a GT3 TA05 that's very good and have joined the FF03 craze and hope to get that working.

We're pretty much in sync on the motor testing, but I rarely test a stock motor on the Fantom any more. Will have to tho cause the last 540s that we got at the Nats were a little different. Haven't had time to take a close look, but will have to break out the magnifiers and dyno and do a little checking. Altho, I have a feeling Doc's miles ahead as usual.
Sounds like me. My Fantom is not much use as of late. My main dyno is usually the APS followed by the load dyno of the BRP. I have not dynod anything since early July. Had my finger on the trigger until the Nat's rules came out. I needed a break after going dyno crazy January thru June. Will be looking forward to battling Docs motors on the track in 2011.

I do have a few cars to build and work on too, F104 and FF03 are part of that
madness.
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Old 09-15-2010, 10:02 PM   #1429
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I was debating on who to quote but there were too many quotes to quote.

On the hypothetical, I would agree with Grandpa and go motor #1. Usually I let my motors run past 1 minute before taking the readings. Some motors can take a bit to settle down. Usually under 3 amps you are pretty safe, unless you way over gear the motors. I usually use 5 to 1 in sedan as my starting point then work down.

If you can run full heats 5-6 min and have a decent temperature, then dabbling in the high 4s can be rewarding. Utilizing the AMB or lap counter system is critical as well as checking the temperature. If you are crowding the 170s then you might need to free up the car some.

I know in Omaha (carpet) I had my motors coming off at 140 deg. Other guys were over geared and I could play the patience game. Like Robk said usually guys would start to slow at the 3-4 min mark. Mine did not really change in a race. Keys were gearing, decent fan and ESC.

For sedan I am into the keep your finger in it mentality. I believe that slowing down creates heat, especially on carpet. Pavement it does not seem to work that well requiring some extra finesse on the throttle. When I raced brushed boats always ran it wide open and feather it quick through the corners. I did not need water cooling or trim tabs like others did and my mod motors came off luke warm after a high ampdraw race.

I am a fan of testing on the track and taking notes.
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Old 09-15-2010, 10:31 PM   #1430
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Wayne et al,

Another fundamental is along the lines of:

Power into motor = Power out + heat (yes, it's a gross simplification, but cut me some slack. My few years of electrical engineering can't be that wrong ). The job of a motor is to convert electrical energy into mechanical energy - loss is the result of less than 100% efficiency, and the difference goes into heat, noise etc.

So, under no load (no power out, effectively), more power in simply means more heat which is waste.

Sustained heat results in more resistance (electrically) and less power. You may recall I documented fade some months back. Refer to attached picture which shows lap times with a definite trend of slowing during the race (this was at the Windsor track).

At the Whalan CC round, I went up one tooth on the pinion, and the motor got 20degC hotter, but my laps times went nowhere. Other guys had rollouts significantly higher than mine, but were no faster (or slower, darn it). Motors that look the same can behave quite differently, so it pays to watch carefully. When they checked the top 3 motors, mine was spinning faster than theirs (still well under the 19k limit), but it just meant we have to gear differently. In classes where gearing is fixed, then more RPM will almost certainly help, but for us, gearing's a free-for-all.

If the bushes are lubed and in good shape, the brushes seating properly and the magnets not clapped out, you should have a race-ready motor. The trick is then making sure your entire drive train is free (I only recently noticed that the front pins on the universals weren't in properly and that was costing me nearly half a second a lap ), gearing properly and then driving like a man (or person) inspired
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Old 09-16-2010, 07:26 AM   #1431
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I'm planning to do a water dip on my silver can but I can't seem to find much info on how long I do it for and how many cycles (1 time or multiple times). Only heard to use 3V
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Old 09-16-2010, 09:08 AM   #1432
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I'm planning to do a water dip on my silver can but I can't seem to find much info on how long I do it for and how many cycles (1 time or multiple times). Only heard to use 3V
I generally use 2v, but that's just a personal preference. Also do most in reverse, but after putting some time on the motors, it's hard to tell which were run in one way or the other or what method was used.

It's very difficult to tell you how long cause there has been a pretty wide variation in brush hardness. The motors we got at the TCS Nats took about 30 minutes to break in. At least that's what the TC guys were saying. I ran Mini so we weren't allowed to take the motors out of tech, so really haven't had a chance to work with any out of this batch of motors.

The last 540s that I have a lot of experience with only took 60-80 seconds to seat the brushes. Even those would have some that took much longer. The best way to do this is to check the brushes visually. If you're not sure what you are looking for, check a brand new motor and a well run motor and see how the brushes fit the comm. You will see that the brush on a new motor only touch on the outside edges. If you run the motor for awhile, you'll see a darker line appear on the outside edges of the comm, and the center will be "shiney bright". What you are looking for is to dip the motor until the comm loses the polished look in the center. Mind you, it will still look clean and bright, but will have lost it's polished look. The other way to tell is to look at the forward or the edge of the brush closest to you and see if it fits flat on the comm like on the used motor. Try dipping at 2v and checking after 20 sec to see what kind of brushes are in that motor. Above all, do not let the water get dirty cause that can ruin a motor.

Now a nit pickey point is that my preference is to just seat the brushes until they make full contact accross the comm. I generally do not dip until the full face of brush fits the comm. Reason, I'm frugal and don't want to leave 40 or 50 runs on the motor in a water jar.

Hope that helps and my apologies to those who know all this stuff to go basic on ya. And to those who didn't, glad to be of help.

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Old 09-16-2010, 10:02 AM   #1433
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thanks, I'll go take a look at a new and out motor later day hopefully i can tell the difference
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Old 09-16-2010, 11:51 AM   #1434
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Sorry to have missed the re-emergence of this thread over the past several days, but I've been on the back side of Italy for the past ten days or so without access to the Interwebs.

I agree with most of what's been posted here & there's a lot of good advice being given. However, we do continue to use both the Fantom and a Motor Master since they give us very different information. We won't sell a Red Dot unless it's been pounded pretty hard on a dyno to make sure it can survive the rigors of racing under load.

As a side note, our full race motors are currently pulling around 19.2K RPM at 5 volts & it's not unusual for us to see 2.5 to 3.6 (!) Amps at 5 volts on a Motor Master with no load. On the Fantom, we expect a power number in the 40's (out of the box is generally in the 20's).

We also suggest that if you have to water dip your motor, use a slave jig & run the slave motor backwards at 4 volts. Otherwise the comm gets all nasty from the stuff in the water being plated to the comm.

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Old 09-16-2010, 02:55 PM   #1435
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Sorry to have missed the re-emergence of this thread over the past several days, but I've been on the back side of Italy for the past ten days or so without access to the Interwebs.

I agree with most of what's been posted here & there's a lot of good advice being given. However, we do continue to use both the Fantom and a Motor Master since they give us very different information. We won't sell a Red Dot unless it's been pounded pretty hard on a dyno to make sure it can survive the rigors of racing under load.

As a side note, our full race motors are currently pulling around 19.2K RPM at 5 volts & it's not unusual for us to see 2.5 to 3.6 (!) Amps at 5 volts on a Motor Master with no load. On the Fantom, we expect a power number in the 40's (out of the box is generally in the 20's).

We also suggest that if you have to water dip your motor, use a slave jig & run the slave motor backwards at 4 volts. Otherwise the comm gets all nasty from the stuff in the water being plated to the comm.

Ciao!
Using a slave motor sounds like a great idea. We run to strict rpm limits out here on the wrong coast so I've been going "old school". It would be nice to just be able to run a motor in and meet the rpm limit w/out that stuff. I remember now that you could pick up a few hundred rpm by chucking up the motor in a drill and cleaning the comm that way----but that was awhile ago so memory may be failing me. Any way, it still sounds lke the way to go.
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Old 09-16-2010, 04:29 PM   #1436
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We also suggest that if you have to water dip your motor, use a slave jig & run the slave motor backwards at 4 volts. Otherwise the comm gets all nasty from the stuff in the water being plated to the comm.
A word of caution using a slave motor is make sure you clean the slots before running the motor. There is a chance of buildup of com/brush material will fill the slots causing the motor to short or even burn up.
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Old 09-26-2010, 11:14 PM   #1437
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I recently picked up a Fantom dyno but it came with a DOS program on 3.5" floppies. Sadly, 3.5" floppy drives are impossible to find around here, and not much point running the DOS program anyways when I understand there is a windows version.

Anyone know where can I get a copy of functional windows based software?
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Old 10-05-2010, 01:45 PM   #1438
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Hello Chaps,
long time since I last was here

Some advice needed. Me and some friends are thinking about competing in an endurance-competition. It will be with Tamiya M-chassis and Silvercan-motors.

ANy advice on how to prepare a silver can for an endurance-race (8 houres!)?
Should we switch motors regurlary?
Or just drive it for as long as it runs?
Any type of Silvercan that is more suited for this type of competition?

Do there exist reddotted Silvercans that are suited for this? If so, where can I find one or two?

thx in advance, guys
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Old 10-05-2010, 05:56 PM   #1439
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A Red Dot 15K would work well for an enduro. Faster than stock but almost as much life. Shoot me an e-mail at [email protected] for purchase information.
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Old 10-16-2010, 12:18 AM   #1440
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Hey I know something about these motors, ive been playing around with them for 10 yrs!..And i won 2 national tiles, regionals, drivers series and I got 2 track records that still stand using these little buggers..actually maybe its 3...
Man I tried everything to run them in nice and in the end it was pretty simple...like less was better ...I think I need another beer before this stuff I didnt tell everyone.
One way of telling a good silver can is looking at the com, some having smaller coms which go faster...I think they mess up the tru at the factory so the lath does another pass or something. Smaller comm equals more brush wrap and more current equals more speed. And the brushes are sometimes lined up so the motor has some timing advance, I have one motor the has both and its been the fastest motor ive had, I should take a picture of it, when you know what to look for you can see it.
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