Throttle issue

UrbanPuma

Esteemed Pedelecer
Sep 11, 2007
675
43
Hi all,

I've noticed the resistance has reduced substantially on my throttle as there doesn't seem to be much oomph required to twist it anymore. Anyone have any thoughts on why?
 

vfr400

Esteemed Pedelecer
Jun 12, 2011
9,822
3,993
Basildon
The problem is that we have no idea how it was before and how it is now. Maybe it was faulty before, and now it's OK. If it still works properly and springs back, what's the problem?

Full-width throttles are not really suitable for electric bicycles, especially bikes with small wheels. They're only thin plastic, and if you hit a bump while at full throttle, the jolt is enough to break the end-stop. They're so weak that you can break the stop, just by twisting. I'd change it for a thumb-type
 

UrbanPuma

Esteemed Pedelecer
Sep 11, 2007
675
43
The problem is that we have no idea how it was before and how it is now. Maybe it was faulty before, and now it's OK. If it still works properly and springs back, what's the problem?

Full-width throttles are not really suitable for electric bicycles, especially bikes with small wheels. They're only thin plastic, and if you hit a bump while at full throttle, the jolt is enough to break the end-stop. They're so weak that you can break the stop, just by twisting. I'd change it for a thumb-type
There was a lot more twisting required to get it to full throttle before, now it's done in one turn and just feels like there's no power. I thought issue was my battery but now think it's the throttle. Seems to take longer to get up to fill speed too. It worked perfectly before and was very nippy from the off, now it's slow on acceleration. Could it also be lose connection from the controller not feeding enough power through to the throttle?
 
Last edited:

vfr400

Esteemed Pedelecer
Jun 12, 2011
9,822
3,993
Basildon
Could it also be lose connection from the controller not feeding enough power through to the throttle?
No.

How's the power from the pedal sensor?

The only way to confirm whether the throttle is working OK is to measure the voltage on the signal wire, while you operate it. Show us the connector if you need any help with that.

As I said above, it's too easy to break the end-stops, which can do all sorts of weird things regarding power. Normally you'd know that you'd done it because there would have been an event that caused it to break: throttle was working OK, big bump, a few swear words, then the throttle isn't working like it should. In other words, it doesn't happen while parked in the garage.
 
  • :D
Reactions: POLLY

UrbanPuma

Esteemed Pedelecer
Sep 11, 2007
675
43
No.

How's the power from the pedal sensor?

The only way to confirm whether the throttle is working OK is to measure the voltage on the signal wire, while you operate it. Show us the connector if you need any help with that.

As I said above, it's too easy to break the end-stops, which can do all sorts of weird things regarding power. Normally you'd know that you'd done it because there would have been an event that caused it to break: throttle was working OK, big bump, a few swear words, then the throttle isn't working like it should. In other words, it doesn't happen while parked in the garage.
Nothing as eventful as that springs to mind lol. I'll take a pic of the connector and report back. Thanks
 

UrbanPuma

Esteemed Pedelecer
Sep 11, 2007
675
43
No.

How's the power from the pedal sensor?

The only way to confirm whether the throttle is working OK is to measure the voltage on the signal wire, while you operate it. Show us the connector if you need any help with that.

As I said above, it's too easy to break the end-stops, which can do all sorts of weird things regarding power. Normally you'd know that you'd done it because there would have been an event that caused it to break: throttle was working OK, big bump, a few swear words, then the throttle isn't working like it should. In other words, it doesn't happen while parked in the garage.
I'
No.

How's the power from the pedal sensor?

The only way to confirm whether the throttle is working OK is to measure the voltage on the signal wire, while you operate it. Show us the connector if you need any help with that.

As I said above, it's too easy to break the end-stops, which can do all sorts of weird things regarding power. Normally you'd know that you'd done it because there would have been an event that caused it to break: throttle was working OK, big bump, a few swear words, then the throttle isn't working like it should. In other words, it doesn't happen while parked in the garage.
From what I can remember, I think the pedal sensor wasn't as powerful either. I've opened the case to the connectors, but not sure which of the four wires on the right side are the throttle
 

Attachments

vfr400

Esteemed Pedelecer
Jun 12, 2011
9,822
3,993
Basildon
Set your meter to 20v (or whtever) and stuff your probes into the back of the connector in the slots where the red and the white wires go in.
 

vfr400

Esteemed Pedelecer
Jun 12, 2011
9,822
3,993
Basildon
Where do I place the probes. Do I need to disconnect the connectors?
[/QUOTE]
Everything must be switched on and connected. I already said, "stuff your probes into the back of the connector in the slots where the red and the white wires go in. " 4th connector down in your photo.
 

UrbanPuma

Esteemed Pedelecer
Sep 11, 2007
675
43
Where do I place the probes. Do I need to disconnect the connectors?
Everything must be switched on and connected. I already said, "stuff your probes into the back of the connector in the slots where the red and the white wires go in. " 4th connector down in your photo.
[/QUOTE]
Ok, inserted probes into slots and results are as follows:

A) Red probe to red wire + black probe to white wire = -1

B) Black probe to red wire + red probe to white wire = 1
 

vfr400

Esteemed Pedelecer
Jun 12, 2011
9,822
3,993
Basildon
Sorr, I made a typo. It should be the black and white wires. Make sure that the probes are reaching the metal in the connector.

Using the red wire, it should still have worked. You should have got about 4v with the throttle closed and 1v when fully-opened.

Using the black and white wires, you should get around 1.2v and 3.8v.
 
Last edited:

UrbanPuma

Esteemed Pedelecer
Sep 11, 2007
675
43
Sorr, I made a typo. It should be the black and white wires. Make sure that the probes are reaching the metal in the connector.

Using the red wire, it should still have worked. You should have got about 4v with the throttle closed and 1v when fully-opened.

Using the black and white wires, you should get around 1.2v and 3.8v.
No problem. I've just re-tested and the reading is 4.98 but when I switch the probes around the reading is 1. What does this mean?
 

vfr400

Esteemed Pedelecer
Jun 12, 2011
9,822
3,993
Basildon
No problem. I've just re-tested and the reading is 4.98 but when I switch the probes around the reading is 1. What does this mean?
It means that you're measuring incorrectly and you still haven't done the important measurements that show the difference between throttle open and shut.

Start again from the beginning:
red probe on red wire and black probe on black wire - should be around 5v
red probe on white wire and black probe on black wire - should be 1.2v with throttle shut and 3.8v with throttle open.

Please post just those three results.
 

UrbanPuma

Esteemed Pedelecer
Sep 11, 2007
675
43
It means that you're measuring incorrectly and you still haven't done the important measurements that show the difference between throttle open and shut.

Start again from the beginning:
red probe on red wire and black probe on black wire - should be around 5v
red probe on white wire and black probe on black wire - should be 1.2v with throttle shut and 3.8v with throttle open.

Please post just those three results.
Sorry, just did it again from standing position and it reads 2.36.
 
Last edited:

UrbanPuma

Esteemed Pedelecer
Sep 11, 2007
675
43
Sorry, just did it again from standing position and it reads 2.36.
Ok. 1st reading 4.30 and second 0.88, but the black probe wire just broke...I'll need to get a new one. Will do test again as it may be faulty
 
Last edited:

UrbanPuma

Esteemed Pedelecer
Sep 11, 2007
675
43
It means that you're measuring incorrectly and you still haven't done the important measurements that show the difference between throttle open and shut.

Start again from the beginning:
red probe on red wire and black probe on black wire - should be around 5v
red probe on white wire and black probe on black wire - should be 1.2v with throttle shut and 3.8v with throttle open.

Please post just those three results.
Readings are as follows:
a) 4.26
b) 0.86
c) 3.53
 

vfr400

Esteemed Pedelecer
Jun 12, 2011
9,822
3,993
Basildon
They're all a bit low, so there could be something wrong with your meter. If it were just the full throttle signal, I would have said that you've broken the end-stop, but I can't draw that conclusion when the other two are low as well.

Have you got a new AA battery you can ckeck? It should be close to 1.5v. If it's lower, your meter isn't reading right.