Getting a 5304 to spin backwards

[Kurt]

I have a plan to mount my 5304 backwards in the rear drop out to solve two issues I have. One being aligning my single speed freewill with my front chain ring and the other is a disk brake clearance problem. by mounting the motor backwards I can solve the two problems in one hit.

Only problem then is I don't fancy riding my bike around backwards So how do I go about making my 5304 turn in the opposite direction? I am running with the digital v2 48a immediate start controller.I remember reading something about a key that some controllers had to switch to reverse. I don't have this.

Can I do it with my controller and how?

Kurt.

 

[Patriot]

That's an interesting idea.

If two of the three main phase wires going to the motor are switched, then the motor will run backwards. With all of the hall sensors setup to operate the motor in a certain way, I'm not sure how smooth the motor with run through its range of acceleration. It may end up with some strange spots when the controller gets signals.

You could always try it, and see what happens. I don't think it would ruin the motor, though I could be wrong.

 

[fechter]

The reverse function on most controllers is limited to low speed. I would not suggest that.

You can reverse the motor direction by re-mapping the hall and phase wires.

As Patriot points out, reversing any two phase wires is the general approach, but you will need to experiment to find the proper hall wire matching. With a 5304, it will be possible to make it run backwards perfectly if you get the hall and phase wires right.

 

[Kurt]

Thanks for the response, It was just an idea and it looked nice in the drop outs backwards. All that space for the disk brake were the 7 speed cluster usually sits. Sound like there would be a bit of playing around to get it to work.

Kurt.

 

[docnjoj]

Won't the threads be reversed? Consider Loctite, I believe!
otherDoc

 

[Kurt]

Won't the threads be reversed? Consider Loctite, I believe!
otherDoc

Both covers have a right hand thread on the boss. It works the same each way. So on the brake side the rotor it stopped by the calliper and the motor cover/ wheel assembly continue to try and spin anti clockwise and self tightens.

On the free wheel side your chain drives the free wheel clockwise tightening it onto the boss.

The only time you need both left and right hand threads is if you want to run a free wheel on both sides.

My old Ezip set-up had a hub like this because the motor us to drive a free wheel on the left.

Kurt

 

[stator]

I'm not certain, but I think the hall sensors might not be centered in the motor phases. They might be optimized for forward operation?

 

[John in CR]

Kurt,

It looks like you have 2 choices to me. 1 re-dish your wheel for better alignment, or 2 flip it over and spin it the other way, which probably requires re-dishing too. Assuming there's not advanced timing for the motor, all you have to do is swap 2 of the motor phase wires, and the required change on the hall wiring won't be swapping the same 2. That should mean that the most combinations that you have to try with the hall wires is 5. I suggest trying all 6 combinations with only slight throttle attempted on each. The one that's the smoothest and quietest on startup and spins in the direction you want should be the single correct one, but take care on your first attempt with load. Caution is recommended because wrong combo's can spin the wheel of most hub motors, but under load a wrong combo can create high current and quickly blow a controller. A bit of care, and systematic attempts of all 6 combos of the Y-G-B colors, and reversing direction is quite easy after swapping 2 phase wires.

John

 

[Kurt]

The dishing of the wheel is ok . My 5304 came more ore less centred between the two drop outs so it sits centred even when flipped backwards way. I think the trouble is my bike like a lot of bikes has 135mm spacing between the drop outs . The motors come with the axle turned down each side to a shoulder and the two shoulders are 135mm apart. The centre line of the hub itself isn't 1/2 way between at 67.5mm its offset to make space for a 7 speed cluster. The left over space on the other side doesn't give you much to work with . If you had 150mm spaced drop-outs it wouldn't be a problem.

a 5304 ,7 speed and disk brake with only 135mm to play with is pushing it. A 5 speed and turning the axle shoulder down on the free wheel side and then some spacers on the brake side would just fit I think.Flipping the motor was just a lazy way of getting around taking the axle out and turning it down on a lathe.

For now I am going to keep my 7 speed and I have just fitted a good v brake on the rear. I all so ordered an Avid hydrologic disk brake for the front and I will see how that combo works first.

Kurt.