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Discussion Starter · #1 ·
I want to upgrade my carrera pro-X nascars.

They need more torque.

Their top speed is wasted, so im willing to sacrifice speed.

They BADLY need more braking. The problem is, pro-X doesnt have dynamic braking and the cars are bricks, so im talking about mechanical resistance that will help to slow the cars.

I was thinking about using a tiny pinion gear with a higher rpm motor. That should give more acceleration and should give more braking.

Are there any motors known for braking?

Any ideas??
 

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QUOTE (darainbow @ 3 Dec 2004, 03:13)I want to upgrade my carrera pro-X nascars.
They need more torque. I was thinking about using a tiny pinion gear with a higher rpm motor. <{POST_SNAPBACK}>

The Carreras are pretty high rpm motors, but they are geared too high, just try the lower gearing on the motors you have. But if the Pro-X doesn't have dynamic braking, you're never going to get much. Sounds like a high banked oval track of R3 and 4 turns would work best. Good luck.
 

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I have heard of some guys over here in Australia who run no brakes but use a spring between the wheel hub and the axle bearing to create resistence. Sort of defeats the purpose of running no brakes doesn't it but they have raced the same track for a long time and don't want to change.

Of course this means you would have to remove a wheel from the axle which can be a problem with those knurled ends as you will have trouble getting the wheel on straight again.
 

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For best braking, with or without braked wiring, the more powerful the motor magnets, the faster they will slow down, all other things being equal of course.

Another helpful motor factor is to have long slim armatures rather than short fat ones - less inertia and momentum. It becomes quite a complex balancing act between rpm, torque and gearing - a cue for entry of Professor Fate, if ever I heard one!
 

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the spring or the extra magnets will aid braking, but they will also reduce acceleration. A motor with better torque and shorter gearing will increase braking AND acceleration (though might reduce top speed)
 

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Discussion Starter · #7 ·
QUOTE (astro @ 5 Dec 2004, 14:00)the spring or the extra magnets will aid braking, but they will also reduce acceleration. A motor with better torque and shorter gearing will increase braking AND acceleration (though might reduce top speed)
<{POST_SNAPBACK}>

I'm trying to put together a digital racing program with some friends that I race 1:1 cars during the summer. They are interested, but the feel and performance of the stock cars is all wrong and im afraid they would lose interest. Because I would like them to prepare their own cars, I dont want to go off the deep end with mods.

I think first I will try a 5:1 gear ratio. This will sacrifice top speed, but give them satisfying torque, and help with braking.

The way they are now, they have no low end torque, but can generate lots of speed; too much to brake off safely without brakes. . . I think more grunt, slightly improved braking, and lower top speed will help balance things out.
 

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QUOTE (PeteN @ 3 Dec 2004, 17:00)The Carreras are pretty high rpm motors, but they are geared too high, just try the lower gearing on the motors you have. But if the Pro-X doesn't have dynamic braking, you're never going to get much. Sounds like a high banked oval track of R3 and 4 turns would work best. Good luck.
<{POST_SNAPBACK}>
Carrera has the same gearing (9:27) than most of the other cars (Scalextric, Fly, etc.)
 

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QUOTE (Crazy-Chris @ 5 Dec 2004, 21:00)Carrera has the same gearing (9:27) than most of the other cars (Scalextric, Fly, etc.)<{POST_SNAPBACK}>

But they are higher RPM motors, so it is still too high. An 8T pinion will help.
 

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QUOTE (PeteN @ 6 Dec 2004, 02:18)QUOTE (Crazy-Chris @ 5 Dec 2004, 21:00)Carrera has the same gearing (9:27) than most of the other cars (Scalextric, Fly, etc.)<{POST_SNAPBACK}>

But they are higher RPM motors, so it is still too high. An 8T pinion will help.
<{POST_SNAPBACK}>

Well, you're the only one who says that the motor has to much RPM...
 

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The Carrera Nascars also have larger diameter wheels than most other 1/32 scale cars so they will have a longer gear ratio for this reason too.

The other problem I have heard with the resistance spring is the motors getting hot rather quickly so you will get a shorter life span for the motor. It does apparently work quite well and helps to even up the braking between the Scalextric cars when compared to the SCX cars which have stronger engine magnets. I think the gear ratio change would be a good first choice.
 

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Go for a high speed, high torque motor and then increase the pinion-to-axle gear ratio. Get the lowest pinion gear teeth number and the highest axle gear teeth.

This will add mechanical brakes, but reduce your top speed. Hence the higher revs in your motor.

Otherwise increase drag (rubber band over the axles, or tighter axle bearings, etc.)...but this will also involve getting more revs to combat straight-line sluggishness.

Don't add weight as this will force you to use more power and momentum will stop brakes.
 

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QUOTE (Crazy-Chris @ 6 Dec 2004, 08:16)Well, you're the only one who says that the motor has to much RPM...
<{POST_SNAPBACK}>

It's not that the rpm is too high, it's that the low end torque is too low. This could have something to do with the excess weight as well. But I think it is the motor, because Monograms seem to have the same motor and the same lack of torque, but are not as heavy.
 
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