R005 Shunt Resistor Mod

[getmo35]

I bought this bike
https://www.ebay.com.au/itm/1644718...BBEV2bDemotion&_trksid=p2047675.c101198.m1985

It has a really tiny controller only rated 36v 15A. I am happy with the speed of the bike but looking to get a bit more torque
I was going to do a shunt mod but there is no shunt, i guess this resistor is the shunt? R005
I guess i have to swap the resistor to a R004 or something?

 

[getmo35]

Well i just found through some deep searching i can control the Amps through the display. I will test it out see if it actually does anything.
*Edit So i found there is a option to show current and it only pulls 14A at the most. I have it set to 20A in the options is there anyway to get it to pull more Amps?

 

[getmo35]

Any help?

 

[E-HP]

Are you climbing a hill to test the current draw (how are you testing?)?

Do you have a pic of the other side of the board?

 

[getmo35]

Yes up hill full throttle it pulls 14A max.
I dont have a photo at the moment but the resistor is on the main power line i assume that is the shunt.
Edit* https://www.youtube.com/watch?v=QbsPzjG-QpA&t=16s&ab_channel=HolmesHobbiesHolmesHobbies
Its the sane controller as this one in the video skip to 40 seconds.

 

[pullin-gs]

Shunt may simply be a section of wide copper trace on circuit board?
For 15 amps max that would be cheapest route to go when engineers designed the controller electronics layout.

 

[E-HP]

Shunt may simply be a section of wide copper trace on circuit board?
For 15 amps max that would be cheapest route to go when engineers designed the controller electronics layout.

I'm guessing a 550 watt, .001 ohm resistor is hard to come by and way more expensive than a little strip of copper alloy.

 

[getmo35]

Well from what i have found is That R005 is a current sensing resistor at 0.005 ohm
I am going to put another R005 in parallel with it to make it 0.0025 ohm

 

[getmo35]

So i ordered a identical controller module to get the current sense resistor of it and also if i blew something up i had a spare.
I could order the resistor but its going to take a couple of weeks international shipping.
So i desoldered the resistor from the spare CM and added it in parallel.

Torque has basically increased by double Since i halved the value of the current sense resistor from 0.005 to 0.0025.
It also hold the max speed alot more often now.
The main power rails are already quite beefy and seems to hold up quite well.

Hope fully this can help someone who has similar controller it seems this is becoming quite common now.
This is what you do not do.
https://www.youtube.com/watch?v=Hmq...ckFilmMakingFlashbackFilmMakingVerified/[url]

 

[qwerkus]

So i ordered a identical controller module to get the current sense resistor of it and also if i blew something up i had a spare.
I could order the resistor but its going to take a couple of weeks international shipping.
So i desoldered the resistor from the spare CM and added it in parallel.

Torque has basically increased by double Since i halved the value of the current sense resistor from 0.005 to 0.0025.
It also hold the max speed alot more often now.
The main power rails are already quite beefy and seems to hold up quite well.

Hope fully this can help someone who has similar controller it seems this is becoming quite common now.
This is what you do not do.
https://www.youtube.com/watch?v=Hmq...e fet will be able to handle the extra power.

 

[getmo35]

Thanks i am yet to hook up the amp meter yet but i would say it has doubled? if the LCD says 14A i would imagine it is 28A
The conroller has 6 of these FETS
Seems like they are up to the job.

 

[mhmtyildiz01]

Hi friend. I need your help. My e bike has a similar controller. Did your speed increase when you added an R005 shunt resistor? My e bike is limited to 25km speed. There are no sockets, wires or jumpers on the controller to exceed the speed limit. I can increase the speed with the display, but the controller does not allow it. How can I increase my speed? Thank you for your help in advance. :thumb:

 

[getmo35]

Hi sorry for late reply have been inactive . This mod will only increase the Amps which won’t effect top speed just more torque .

 

[ZeroEm]

Still working, then great mod. keep up the good work.

y getmo35 » Sep 29 2021 7:04pm

Hi sorry for late reply have been inactive . This mod will only increase the Amps which won’t effect top speed just more torque .

 

[DogDipstick]

Hi sorry for late reply have been inactive . This mod will only increase the Amps which won’t effect top speed just more torque .

The mod certainly *might* increase top speed, friend.

If he did not have the capability to pull full load RPM, before.. under the old system, amps will certainly reach a higher RPM movement of the stator.

Like my BBSO2... YOu can set it at 10A, 52v,... and you will only go ( 520w) about 20mph... Same voltage.. and if you have 20A.. I can go ( hold) 30mph.... Load.

Load load load. Load is always there.

 

[EndGame00]

How is the uphill climb with the shunt mod?