Phroz

iTrader: (1)

I just put a Mamba 7700 in my XXX-S. I'm using a 86t spur and a 19t pinion (48 pitch). Today i noticed after breaking that the spur and pinion seemed to be slipping and on closer inspection i noticed the spur has worn down (only about the 6th pack on this spur) I turned the breaking down to 65% on the ESC to try and stop it hapening again (had it on 80%) Also should these things get hot? I Have turned the timing down to lowest but the motor and batts (3500mah nimh) get pretty hot (the ESC seems to hum along nice and cool). I have checked the belt to make sure its not too tight and the car seems to roll pretty freey. Also (yes another also lol) would i benifit from changing to 64 pitch spur/pinion?

Cheers,

Ben.

CRASH

iTrader: (26)

Sounds like your gear mesh is to loose. Also your motor and batteries should get pretty warm, especially with the 7700.

Later,

I)arkness

iTrader: (7)

i think your ratio is to high with 8.28 try gearing it down and then check the temps

Phroz

iTrader: (1)

so gearing is spur divided by pinion? ie 128t spur / 15t pinion = 8.53 ?

I)arkness

iTrader: (7)

no

ratio =

its the spur/pinion x the internal ratio which is 1.83

86/19*1.83=8.28

Phroz

iTrader: (1)

ok just out of interest how do u work out that internal ratio?

I)arkness

iTrader: (7)

each car has its own ratio it should be on the manual

but i think i has somthing to do with the diff sizes

Phroz

iTrader: (1)

great! just read that.. cheers! so givin this what FDR would u suggest i run for the 7700 ( i think its a 3.5turn to 4turn motor)

I)arkness

iTrader: (7)

im not sure on that your better off posting that in the xxx-s forum as heaps of people would help you out

http://rctech.net/forum/showthread.p...47#post3238947

RussB

internal gear ratio is diff pulley / layshaft pulley. overal gear ratio is (spur / pinion) x internal ratio.