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Discussion Starter · #1 ·
So why do you think that is? I have a Bentley and an Audi R8R in standard form and both of them have the twin-magnet chassis running on standard 9/27 gearing. I use a parma and a PM controller and both the tracks I run my cars on are wired with brakes. I mean the problem must be in the cars themselves since every other car run properly.

I recently bought a Porsche 911 RSR and removed its original motor and reverse switch. The magnets were then removed and I've installed a Slot.it 25k motor running on 9/27 gearing. I originally thought the culprit was the motor itself or all those wiring but now the lack of braking problem is still there even with a new motor. Could it be the weight of the car? Or do you think it might help if I use a lower gearing, say 8/27 instead? Surely there's a way to sort this out, no?
 

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Graham Windle
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Apart from the weight one thing nobody takes into consideration is that an electric motor always runs faster in one direction ,the reason being either the moror is timed to run in that direction or the direction the wire is wound on the armature will determine its fastest direction.
Carrera cars have the crown gear on the oposite side to slot it ninco scalex etc so the slotit motor will run in the opposite direction,the brakes and the performance will be impared as the motor is not running with maximum efficiencey this coupled with the weight will show up as poor braking .Try turning the axle over and swapping the lead wires over to see if it makes a difference you will have to cut a slot in the chassis to clear the gear .I run slot it v12s at 13/32 and still get good brakes and acceleration.
I am currently prepping a carrera bently for an article for later this month which might help
 

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looking forwards to the results of this 'reverse motor' theory - certainly sounds promising!

I always assumed it was the motors or the weight, but I changed to 8/27 on the ferrari 575, which helped, but its still not as impressive as I expected..

The other cars with poor braking are Revell ones, they too have the motor the Carrera way round...
 

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Dumb question...if it is because the motor is running the "reverse" way, wouldn't it be quite simple to pop out the rear end assembly and flip it around and see if that's true or not? I had always thought it was their motors too. Have to give that try myself...Carrera brakes aren't that bad compared to the Revell-Monogram's that one has to constantly remind oneself to let off a lot earlier for that first turn or...
 

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Almost all my Carreras and Revells will need some work to the chassis to try this - there is an assymetrical dip for the crown wheel. However, my Carrera Enzo has a symmetrical chassis, so I flipped the crown on that one, and with the switch still installed, changing polarity was a doddle...

the result? if there is a difference, it is a subtle one. Mind you, I think the motor needs running in again in this new direction.
 

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Graham Windle
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QUOTE wouldn't it be quite simple to pop out the rear end assembly and flip it around
isn that what I said?

QUOTE Try turning the axle over and swapping the lead wires over to see if it makes a difference you will have to cut a slot in the chassis to clear the gear


astro the enzo is an extremly heavy car so the benefits may be less
 

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Not exactly the most scientific test but........

I just set up a basic oval (12ft straights) using scaley sport track, std wall-wart and parma 45ohm controller. I used two identical Carrera Panoz LMP07 (Sebring 50th Anniversary versions). These were box standard, brand new and therefore no gluing/truing or any fettling at all (except ensuring the variable mags were in the same place).

I simply popped the axle assembly and flipped it over on one car (just enough room without a dremel) then switched the polarity over and place a marker on the car so I knew which was which.

What then followed was a bout of enthusiasm over science. Each car was run in the same lane over 20 runs. Each run consisting of the car at the start line (top of the back straight) then full throttle until the braking marker was reached. I then released the throttle completely and marked where the car stopped (rinse, repeat).

Measuring each one and then taking an average found this:

Standard Panoz LMP07 - Avg. stopping distance 156 cm

Reversed Axle Panoz LMP07 - Avg. stopping distance 144 cm

Now not a great improvement, but still an improvement and these are perhaps not the most recent of carrera's so other cars may present a better test. Just for comparison, I also ran a few other cars on the same test to see how they braked (all of these are box standard except for glue n true):

Scalextric MG Lola - 81 cm

SCX Dome Judd - 68 cm

Spirit Lola (not racing version) - 70 cm

Fly Panoz 56 cm

Pretty dramatic difference between carrera and the competition
 

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nice tests!

Similar to my enzo testing, which even less scientifically (it seemed to stop a bit sooner!) - the change was not as radical. And also, like The Muffin Man, I find Carrera stopping distance to be about twice that of other cars. This is a huge difference, so motor direction whilst a factor is not the main culprit...

Purely weight?

More experiments are needed by someone with some carrera cars, some other cars, some weighing scales and some lead weights!!!
 

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Discussion Starter · #14 ·
Hmmm........very interesting results indeed, and rather dramatic results when compared between Carrera and other brands! How much influence do you guys think magnet drag has on braking? Also how can you tell which is the intended direction of a motor?
 

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Graham Windle
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with the bently you need to grind a touch out of the body to clear the gear it doesnt take much.you can also run the car on the guide in tripod form to increase the rolling resistance by fitting gom tyres on the front all this will increase the brake effect.if thats still not enough changing the gear ratio to 8 /27 or 8 /30 will help.
 

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Allan Wakefield
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So far I have removed 20 grams of weight from an Enzo, split between body and chassis. That is JUST waste plastic, NOT interior or detailing.

So yes Carrera bodies are heavy compared to other makes but then Carrera themselves have said they don't make racing cars, they make toys. So I guess their priorities are different from the likes of Slot.It and the Fly racing department.
 

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QUOTE (Crazy-Chris @ 27 Oct 2004, 18:14)@muffinman:

And you are sure that the Panoz both have the new chassis ?
Otherwise, forget it.
<{POST_SNAPBACK}>

No, I believe they are the old style chassis. However, they are both identical and the purpose of the test was to check Grah1's comments about the motor running the wrong way. So for this purpose the chassis is irrelevant.........it was just useful to have two identical cars to check the theory.

The other distances I quoted were for reference as I was curious whilst running the test so thought I may as well post em


I personally love carrera cars because I like the level of detail and the solid build quality. I have no issues per-se with their braking as you either get used to it, or race like against like. So please don't take this as carrera bashing......it's just I had two identical ones to run the test on. In fact i've now found I've got a couple of identical spirits and revell's too............so i'll re-run the test with those as well later this week.
 

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QUOTE (The Muffin Man @ 27 Oct 2004, 13:19)Not exactly the most scientific test but........

I just set up a basic oval (12ft straights) using scaley sport track, std wall-wart and parma 45ohm controller. ...
What then followed was a bout of enthusiasm over science. Each car was run in the same lane over 20 runs. Each run consisting of the car at the start line (top of the back straight) then full throttle until the braking marker was reached. I then released the throttle completely and marked where the car stopped (rinse, repeat).

Measuring each one and then taking an average found this:

Standard Panoz LMP07 - Avg. stopping distance 156 cm

Reversed Axle Panoz LMP07 - Avg. stopping distance 144 cm

I also ran a few other cars on the same test to see how they braked (all of these are box standard except for glue n true):

Scalextric MG Lola - 81 cm

SCX Dome Judd - 68 cm

Spirit Lola (not racing version) - 70 cm

Fly Panoz 56 cm

Pretty dramatic difference between carrera and the competition

<{POST_SNAPBACK}>
I always thought that scalextric had poor braking cars ?! On another forum there was a complain about scalex cars not braking compared to scx, ninco..
I only have one remark on this 'non scientific' brake test: difference in braking is also caused by difference in speed at the brake marker on your track.
I only have scalex cars (few scx too) and the longest brake distance with standard car at 12V without dynamic braking was 340 cm wit a scalex Indy Mobil. I believe the weight of car and braking characteristic of de motor is most important. I plan to do some extensive brake tests in near future. Brake distance is most of the time measured as a distance after letting the car speed up for a certain distance or let it go to top speed. At least the speed at moment of braking should be measured so that braking can be expressed as a negative speed measure -nn m/s. This is not so easy to measure with simple means..
How about measuring the time to travel 1 m with full trottle and the time to travel another meter with full braking ? If you divide the acceleration time with the braking time don't we have a objective braking indicator ?
 
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