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View Full Version : tell me about motors.. and slippers for that matter


mx0range
07-11-2007, 01:29 PM
as i said in the tamiya section, iv just ordered a df-03 and some upgrades. asked what motors recommended and was told a 19t motor. now the speed controller i have says its for 20+ turns (its a futaba, would a 19t fry it?) so..

what exactly is the difference between motors with fewer or more turns? does it have any relation to its rpm / torque? more efficient?

and whats a slip clutch thing for since there's no gears? iv ordered 1 anyway on the recommendation of the review ;)

tia :)

ashleyb4
07-11-2007, 01:46 PM
Ok motors and there winds.

The lower the number the faster the motor so a 10trn motor is faster than a 19t motor. Your speedo wont take a 19t motor the motor limit means 20 and higher or slower motors so it will handel a 27t motor for example.

A slipper clutch is something that attaches to your spur gear (the big gear by the motor) all this does is take away some of the bite it stops you from destroying your drivechain and it makes the acceleration of a fast motor controlable. And they can be ajusted to suit diffrent tracks.

A

Hope ive helped.

Lee Martin
07-11-2007, 01:52 PM
Slippers are design in a way so that it acts like a clutch when applying power....

for example...in a real car you can control the slip the clutch gives by releasing the pedal slowly....althoughing the car to grip and not wheel spin.....

raise the revs and release the pedal aggressively and boom..wheel spin....

made worse or better by conditions, ice for example, compared to dry tarmac, you would apply different actions to allow the car to grip.

now scale this down and thats all its doing. a looser slipper allows the car to have more clutch action and there for is like letting a real clutch out slower, whereas a tight slipper is like the aggressive clutch action.......

also with the power we have the cars can wheely etc...so it can also stop that.

a lose slipper is better through bumps etc as its not trying to rip a hole in the ground with power aswell..

hope this helps...although may confuse!!! ;-S

mx0range
07-11-2007, 02:01 PM
understood. but.. if its set loose wont that stop the car from moving at slower speeds? (guessing it works like the clutch on my cen gx1 nitro)

one other thing i forgot to ask.. this front 1 way thingy - i forget the exact name - does that mean the car will only move 1 way ie forward :confused:

jimmy
07-11-2007, 02:05 PM
with any one way (front or centre) only the rear wheels will be engaged off-power, or likewise in reverse. But if you're using reverse then you're probably not racing and maybe a one-way isn't the setup for you anyway? I do think it's more fun to drive though.

mx0range
07-11-2007, 02:10 PM
iv spent enough so far on this thing that i may aswell try and get it racing! an expensive toy to just use on the street otherwise (i have a real car for that :p)

but why is having reverse in a race a bad thing??

VintageRacer
07-11-2007, 03:00 PM
but why is having reverse in a race a bad thing??

It's not necessarily, it's just that most ESC's that are designed for competition don't have reverse.

Having not raced competitively for ages I don't know what the current reasoning behind that is, but when I was... ESC's usually used a relay to switch between forward and reverse creating more resistance and adding weight.

Southwell
07-11-2007, 03:04 PM
Reverse is illegal at BRCA events i believe. Most reversible speedos can have the reverse turned off for these meetings though.

jimmy
07-11-2007, 03:27 PM
I thought it was because reversing out in front of cars racing around could cause a right mess? There's not much use for reverse usually on the race track as most of the time when you are stuck you are upside down - you can usually drive over most things if you get stuck on them but not always.

example is Hayato in leg one of the Worlds A main when he hooked up on a corner by turning in too tight. He lost the leg because of it - but he would have ruined Ryan Maifields leg win if he had been able to reverse out of it into the path of Maifield.

Southwell
07-11-2007, 03:42 PM
I thought it was because reversing out in front of cars racing around could cause a right mess?

Yeh, i think thats the reasoning behind it.

VintageRacer
07-11-2007, 05:05 PM
Makes sense. Do F1 or rally cars have reverse?

Southwell
07-11-2007, 05:17 PM
Makes sense. Do F1 or rally cars have reverse?

What like the real cars? Yes :confused:
If you mean RC one, which is more likely, then it depends on what speedo is in it.

Gaz_Stanton
07-11-2007, 07:05 PM
Yeh, i think thats the reasoning behind it.

It's also to allow proportional braking with a 2 channel radio.

mx0range
07-11-2007, 07:26 PM
while looking at some motors iv come accross a few that are, for example 9x2 (double) so would that be 9 turn or 18 :confused:

ashleyb4
07-11-2007, 07:32 PM
The second number means the amount of wires rapped around the armature so a 9x2 would have 2 pieces of wire rapped around 9 times and a 9x1 would have 1 wire rapped around 9 times.

A

VintageRacer
07-11-2007, 08:04 PM
What like the real cars? Yes :confused:
If you mean RC one, which is more likely, then it depends on what speedo is in it.

I meant the real ones.

VintageRacer
07-11-2007, 08:05 PM
It's also to allow proportional braking with a 2 channel radio.

My old 80's Nosram has proportional braking and reverse, or at least I believe it has.

Southwell
07-11-2007, 08:25 PM
I meant the real ones.

They have reverse but it's difficult to engage as it's not likely to be used a lot.

MK999
07-11-2007, 09:00 PM
I didn't think F1 cars had reverse, it's never used and would only add weight? That's why you always see pit crews pushing cars back. Rally cars do have reverse as it's helpful for removing the tree from your bonnet :D

Gaz_Stanton
07-11-2007, 09:36 PM
My old 80's Nosram has proportional braking and reverse, or at least I believe it has.

Some did a while back but they were not great for racing. Either you have to split stick movement between braking and reverse. (i.e. not much braking resolution) or they had a delay that would only activate reverse after the stick was held back for a couple of seconds.
If it was the split movement type you could easily find the car going into reverse mid braking if you moved the stick slightly too far back. :wtf:

Southwell
07-11-2007, 10:02 PM
I didn't think F1 cars had reverse, it's never used and would only add weight? That's why you always see pit crews pushing cars back. Rally cars do have reverse as it's helpful for removing the tree from your bonnet :D

Heres an article i found: http://www.f1technical.net/articles/66

VintageRacer
08-11-2007, 09:11 AM
Some did a while back but they were not great for racing.

I recall this particular Nosram ESC was used by most of the top UK drivers at the time (I was not one of them :( )
There was one on Ebay recently, although it was the 2nd generation with a hard case. Mine has a heat shrink case!
http://cgi.ebay.co.uk/Nosram-ESC_W0QQitemZ270179584657QQihZ017QQcategoryZ2565QQ ssPageNameZWDVWQQrdZ1QQcmdZViewItem

Either you have to split stick movement between braking and reverse. (i.e. not much braking resolution) or they had a delay that would only activate reverse after the stick was held back for a couple of seconds.


Mine did the delay thing. It somehow knew when the motor had stopped, waited a fraction of a second then engaged reverse. I found I tended not to use reverse much and after I bought it, Nosram released a forward only version!!

VintageRacer
08-11-2007, 09:14 AM
Heres an article i found: http://www.f1technical.net/articles/66


Taken from the above article:
"The regulations state that the cars must have at least 4 and no more than 7 forward gears as well as a reverse gear"

I can't say that I've ever seen an F1 car going backwards using it's own power.

RogerM
08-11-2007, 12:17 PM
When numpty nuts stuck his McLearen into the gravel trap at the pit entry his wheels where definately rotating backwards in an attempt to get out.

Robbiejuk
18-11-2007, 04:40 PM
Yeah anyways back on radio control cars. You really wouldn't want to be using reverse with a schockty diode on. They don't like revers polarity. :D