GC StReeT DRiFT

Hey guys

Need a lil help with choosing the correct pinion gear for my pro d, after running it tonight, had issues with it drawing too much current and overheating due to working the motor too hard.

I think the pinion gear it came with is for a 540 standard motor.

Im running a 60a Brushless Sensorless easy run system with 9 turn motor.

Anyone thats had any experience with this chasis offer any help?

Or know where i can find some? Im very new to RC thankyou.

VenturaDC

iTrader: (32)

how long did it take to overheat?

i dont know the pro d but for drifting you dont need an exact gear ratio, just something you can run hard and be safe.

I would start out with a pinion about 5 teeth smaller then you have now and try again. If it still over heats keep going smaller 1 or 2 teeth at a time till you can run the whole pack without over heating. if it stays cold after the whole pack you can go back up one tooth at a time to get more speed back out of it

GC StReeT DRiFT

Umm at first it was cutting out intermitenly but this was as soon as I start running it so motor wasnt even hot then, but apparently drawing too much charge.

Both steering and throttle would cut then turn on and off and it would be fine again.

Then I could run it for a while without any problems (20-25min) then motor gets really hot, then I noticed just the throttle was cutting out, still had steering though.

Only thing I could put it down too was the ESC cutoff for overheat or overload protection due to wrong gearing, everything else seems fine.

nickvig

iTrader: (13)

9 turn brushed or 9 turn brushless?

GC StReeT DRiFT

Brushless.

Its a Hobbywing EZRun 60A Sensorless System.

GC StReeT DRiFT

Well i went and bought a 26t pinion gear today and tested it and doesnt seem to be much difference, it handles and drifts a bit easier though, however i ran my lipo again tonight and was going strong for a good 45 min or so and its cut throttle again.

Tested it when i got home and all 3 cells are sitting around 3.6 - 3.7v per cell, charged it too 4.2 before i left.

Any ideas? Dodgy battery maybe?

Its an RC Power 4000mah Lipo cheapy, was $20 icluding shipping.

charlessito

iTrader: (11)

ezrun system are famous for being hot, final drive of 7-8 will be enough for your pro d.

charlessito

iTrader: (11)

lipo should not have drop voltage so much. if you full charge it to 4.2 per cell it should hold charge even after a month. and yes a 4000 for only 20 bucks is dirt cheap

GC StReeT DRiFT

Its a 4000mah 11.1v 15c Lipo.

When i got it i gave it a full balance charge at 3.8Amps.

Am I missing something when charging? Whats with discharging a battery and whats the 15c part mean?

GC StReeT DRiFT

ok so im still having a few issues.

I changed the pinion gear to a 26t from a 31t, its still getting hot but I dont think the pinion was the problem of it throttle cutting.

Im thinking its actually the battery now. Although it was branded as 4000mah 15c, 3 cell lipo, it was only $25 so i dont think its the real deal. Its dropping from 4.2v per cell to 3.2v per cell within a matter of 40 to 45 min, a 4000mah should be lasting longer than that right?

My mate has the same setup, same battery and we ran it the other night and it lasted around 45 min or so then hit lipo cut. Went back to charge it, and bam "charge error" low voltage, tested the cells, 3.8, 3.7, 1.5 !!! Goodbye cheap Lipo, do u guys think this is the problem?

It says on the battery, Do not charge over 1amp, my battery charger can charge up to 5amps, and I read somewhere u could charge a 4000mah anywhere up to 3.6amps?

Any advice and help would be much appreciated, in regards to batteries charging and gearing advice, thanks.

VenturaDC

iTrader: (32)

is that 45min of running the car or just sitting on the shelf?

if its 45min of running time that is more then i would expect. its cutting out because your hitting the lipo cutoff.

with a 5300mah 28c with a 17.5 i get about 30 min of run before it cuts out.

i would say there is nothing wrong

GC StReeT DRiFT

Yeh about 45 min running time.

As with the charging question, how do u work out what max amps to charge it at based on mah value?

Do u have anything to add regards to gearing wise? Or doesnt it really matter what pinions you run when your just using it for drifting?

VenturaDC

iTrader: (32)

Nah gearing sounds fine, if your making 45min with out it shutting down due to heat then your fine. You can go even smaller with the pinion if you want it to start drifting earlier. the smaller the pinion the more down low rip youll have for breaking the tires loose.

The rule of thumb for lipo charging is 1 amp for every 1000mah

so 4000mah= 4amp charge.

GC StReeT DRiFT

Yeh thats what i thought, any reeason why it wud say dont charge over 1amp on the battery?

Also whats the 15c part of the ratings mean? Is it better to have a higher C rating with a Lipo?

Ay Way Way

iTrader: (3)

they probably meant don't charge over 1amp for every 1000mah.

The C rating is the current your battery is putting out, multiply your c rating with the MAH then divide by 1000 and you get an idea of how much amps it is putting out. 15c*4000 = 60000 /1000 = 60amps

I always get a battery that has around 30c for my cars.