Dial down 1000w hub motor by lowering Amperage

[MrTuvix]

Hi,

I have a front wheel 1000w hub motor and want to use it for my ebike to give me AWD, the motor itself is too powerful for my aluminium front forks.
I don't need a 1000w up front as I have that on the rear, I really just want to reduce the torque to have it help me up hill's without ripping the front forks apart, would reducing the amperage through the controller (sw900) be an option or would anyone have any suggestions?

 

[DanGT86]

Current is directly proportional to torque. If you can program your controller then reducing the current is for sure the best way to reduce the torque.

You could also look into the ramp rate of the throttle if that is adjustable. The total current might not be as bad on the fork as a fast ramp rate.

 

[MrTuvix]

Current is directly proportional to torque. If you can program your controller then reducing the current is for sure the best way to reduce the torque.

You could also look into the ramp rate of the throttle if that is adjustable. The total current might not be as bad on the fork as a fast ramp rate.

Hi Dan thanks for the reply, ye both are adjustable on the controller just want a slow gradual acceleration off the front I'll give this a try and hopefully it doesn't tear the forks apart

 

[amberwolf]

if you use correctly fitting torque arms installed properly on the axle, there won't be a problem with the fork. i've used a couple thousand watts on a middling-poor aluminum suspension fork just fine by ensuring the axle couldn't move at all on both ends. that was on my 2wd crazybike2, which has a thread around here somewhere--start at the end of the thread for that configuration because it went thru a lot of changes before reaching that.

ebikes.ca has some good torque arm options, the best of which are the clamping/pinching type as the axle cannot rotate with those if the rest of the arm is secured to the fork sufficiently..

waht controller do you have? some are adjsutable and some arent'.

if you want to add throttle ramping you can do it in a few ways if the contorller doesn't support it. one of the more useful ones is to get the ebikes.ca cycle analyst v3.x because it not only supports the ramping and current limiting, etc., it also is a battery / etc monitor.

 

[MrTuvix]

Hi,

Amber wolf the controller is the SW900 and it has the options of Current-limiting of Controller 1 - 20A and it has Zero start & Non-zero Start option also I think that is what is meant by changing the throttle ramp rate.

I checked out those torque arms on ebikes.ca, they are something else never knew such things existed far better than the ones I ordered I will definitely order two of these hopefully they deliver to Ireland .

If you have a link to that configuration thread for setting it all up in your crazybike2 it would appreciated thanks for the help!

 

[amberwolf]

Hi,

Amber wolf the controller is the SW900

afaik, sw900 is a display, not a controller. what does the display connect to? that will usually be a metal box between it and your motor, with more wires going to your throttle, brakes, pas, etc.

and it has the options of Current-limiting of Controller 1 - 20A

then you can lower the current thereif you need to.

and it has Zero start & Non-zero Start option also I think that is what is meant by changing the throttle ramp rate.

usually, yes. nz start is probably ramping and z start is probably nonramping.

EDIT 081123: that is wrong per E-HP's info from the manual.

If you have a link to that configuration thread for setting it all up in your crazybike2 it would appreciated thanks for the help!

i don't have a link, but there should be pics of the wrenches i used as torque arms (not nearly as good as actual torque arms, but they worked). probably right around where there's a picture of yogi bear the st bernard getting his head stuck in the rotor/wheel i had leaning against the wall. back in 2014 or 2015 probably.

 

[MrTuvix]

Hi,

The controller is a 12 MOSFET, I will definitely buy those clamping torque arms you suggested, a bit pricey but they will be worth it for the piece of mind. I found the thread thank you, when you said crazy bike you meant it, what a machine fair play the spanner torque arms are a feat of genius!

 

[E-HP]

Hi,

Amber wolf the controller is the SW900 and it has the options of Current-limiting of Controller 1 - 20A and it has Zero start & Non-zero Start option also I think that is what is meant by changing the throttle ramp rate.

I checked out those torque arms on ebikes.ca, they are something else never knew such things existed far better than the ones I ordered I will definitely order two of these hopefully they deliver to Ireland .

If you have a link to that configuration thread for setting it all up in your crazybike2 it would appreciated thanks for the help!

What controller is it? Careful assuming that zero or non-zero start has to do with ramping. For instance, KT controllers have those options (P4), and in that case, non-zero start means the throttle doesn't function until the controller senses you pedaling with PAS. If you are using the SW900, then it isn't a KT controller, so could be different. Did you check the manual?

EDIT: looks like it has some similarities to the KTs if you are using PAS:
P09 Zero start & Non-zero Start. 0 is Zero Start, 1 is Non-zero Start
P10 Driving mode. 0 is driven by PAS. Throttle is useless at this time. 1 is driven by Throttle. PAS is useless at this time. 2 is driven by PAS & Throttle. Throttle is useless at Zero Start status.

https://f.hubspotusercontent10.net/hubfs/7933366/Hub%20Drive%20Display%20Manual.pdf

 

[amberwolf]

Hi,

The controller is a 12 MOSFET,

But which controller is it? There are probably hundreds of thousands of 12FET controllers. A pic of the label on it would probably help.

I found the thread thank you, when you said crazy bike you meant it, what a machine fair play the spanner torque arms are a feat of genius!

I copied that idea from many others here that did it before me.

 

[MrTuvix]

But which controller is it? There are probably hundreds of thousands of 12FET controllers. A pic of the label on it would probably help.



I copied that idea from many others here that did it before me.

 

[MrTuvix]

What controller is it? Careful assuming that zero or non-zero start has to do with ramping. For instance, KT controllers have those options (P4), and in that case, non-zero start means the throttle doesn't function until the controller senses you pedaling with PAS. If you are using the SW900, then it isn't a KT controller, so could be different. Did you check the manual?

EDIT: looks like it has some similarities to the KTs if you are using PAS:
P09 Zero start & Non-zero Start. 0 is Zero Start, 1 is Non-zero Start
P10 Driving mode. 0 is driven by PAS. Throttle is useless at this time. 1 is driven by Throttle. PAS is useless at this time. 2 is driven by PAS & Throttle. Throttle is useless at Zero Start status.

https://f.hubspotusercontent10.net/hubfs/7933366/Hub%20Drive%20Display%20Manual.pdf