I don't understand - RC-Monster Forums

Hickoryhead · **I don't understand -** 10.01.2007, 10:54 PM

Ok. I might be missing something here. In a thread called “noob e-revo” in the “revo” threads Jthiessen posted #34 which states

“When you do end up going brushless, just remember that your tranny is backwards. I forgot all about that, and when I put a sensored system in it (HV-Maxx), I ended up having to flip the diffs to get it to run in the right direction.”

When I built my E-Revo with an Emaxx transmission I didn’t know what direction was front and rear. So I went to the Traxxas website and looked at gallery pictures of the Emaxx and placed my transmission in the same direction with the motor pointing to the front. I am running a Lehner 1950 1800kv. Do I need to flip my transmission around? When I put everything together my Gevo was running backwards. I am using a MM for ESC. I flip flopped 2 wires coming from the motor to the MM. It then ran forwards. I am just wondering if I hooked everything up correctly or if I need to flip the Transmission around.?.

Help!!!!

_paralyzed_ · 10.01.2007, 11:06 PM

an e-maxx transmission spins opposite of a t-maxx(or revo) transmission, so you have two options. 1. flip the diffs 2. flip the tranny Switching the wires may have solved your problem but when running forward your esc may actually be putting out reverse power which means no brakes and instant switch to forward power when you try to apply the brakes, and unless your esc is setup for %100 reverse power you may not be getting full power when running forward. I prefer flipping diffs to turning the tranny, but it depends where you need the weight of the motor

_paralyzed_ · 10.01.2007, 11:13 PM

p.s. if the tranny is in the normal e-maxx way and you left the diffs alone your esc is probably running backwards, standard mm programming allows reverse to stop to forward transitions, but when going forward you have to stop, wait three seconds, then you get reverse so, can you go reverse to forward? or do you have to wait three seconds after reverse to go forward, cause then you are backwards, and if you can go straight from forward to reverse you are backwards

BrianG · 10.01.2007, 11:57 PM

For sensoredless motors, all you have to do is swap any two of the motor wires if the motor spins the wrong way. Direction is only a concern with sensored motor systems.

Hickoryhead · 10.02.2007, 01:59 AM

I think the 1950 is a sensorless motor right? So I should be fine with just switching 2 wires the way I did. Or should I turn the Transmission around?

jnev · 10.02.2007, 02:08 AM

Correct. The 1950 is a sensorless motor.

Hickoryhead · 10.02.2007, 02:11 AM

So there is no reason to have to turn mine around. Thanks.

Patrick · 10.02.2007, 07:02 AM

That's right. The sensorless esc's don't care which way your motor's spinning.
In the other thread they were talking about flipping the tranny when using the HV system, because it's sensored and you can't just swap the wires on those to reverse direction.

lincpimp · 10.02.2007, 10:12 AM

And I have asked, and no one seems to have had problems with turning the tranny around. The gears in the tranny do not seem to mind which way they are going.

suicideneil · 10.02.2007, 08:06 PM

Its a bi tranny.... (bi-directional transmission). Another funny, Im on a roll lately.

10.02.2007, 10:02 PM

Thanks for answering that quest - I'm planning on running the single speed trans one way in the flm Emaxx I'm finishing up and pointed the other other way in G2R thats not quite as far along, been warned it needs the weight forward. Otherwise, its one of those that will endo from a standstill.

suicideneil · 10.03.2007, 06:42 PM

Yeah, both the maxx and revo will happily do backflips with a good BL motor on board, and having the weight a bit farther forward also helps put weight over the front wheels to aid steering.... though then over steer starts to become a problem if its too far forward. So much fun setting these things up right isnt it.....