Throttle and motor noise

[KirstinS]

I've just changed an old throttle - jut a basic thumb one as I broke the old one.

Oddly the motor is now far far quieter ? There is no doubt whatsoever and def motor noise rather than spokes/discs/guards causing it

It is back to how I remember it being before I swapped controllers from 8fun own to a ku65

The old throttle was pretty rusty inside and both are soldered to the controller

Could a dodgy connection cause motor noise ??

 

[Deleted member 4366]

The throttle is only a signal wire, it's the controller that does everything that affects noise. Motor noise increases with current, so it's probable that your new throttle doesn't give such a high signal, and you don't get as much power. Is the no-load speed the same?

All the throttles I've seen are made of plastic. what exactly was rusty inside?

 

[KirstinS]

thanks - i'll have to test it and revert

was a bit slower this morning and there was no wind. hmmm

can one change the signal if is giving out a low one ? Or is it just a case of buying anotther

 

[Deleted member 4366]

First step is to measure the throttle signal.

 

[e-bike]

I would think you will need to buy another one. My controller says throttle voltage 1.1 – 4.2v but when I test the voltage I get 5.2v

You need throttle that can handle 48v + but don’t put me 100% right d8veh would know far better then me.

The throttle you brought what volt controller did it say its for?

 

[Geebee]

Throttles don't care what the battery voltage is, they run off a 5v line, the battery voltage is only relevant if it has a battery gauge on it.
If you measure the wires to the throttle there should be a positive (red), negative (black) and signal (yellow) but they do vary in colour what you need to measure is the voltage at the signal wire at full throttle, meter between the negative and signal.

 

[averhamdave]

You need throttle that can handle 48v + but don’t put me 100% right d8veh would know far better then me.

I didn't know that. I'm building a bike up at the moment from surplus parts and the throttle I've just fitted will be working at 36v but I have had the same one working happily at both 24v and 48V. surely the throttle only ever sees 5v, regardless of the main battery input voltage?


sorry Geebee beat me to it!

 

[Deleted member 4366]

The throttle runs off a regulated 5v supply from the controller regardless of the battery voltage, so all throttles are 5v, not 36v, 24v or 48v. As already pointed out, some throttles have LEDs in them, which is a separate system. They take power directly from the battery. No harm will be done by connecting to the wrong voltage, but the LEDs won't indicate properly with the wrong voltage, because they are in effect a voltmeter.

 

[KirstinS]

Well, no load speeds are the same (with 0.4mph) which can be accounted for by just about anything.I cant measure the actual output without totally dismantlelling my controller/housing. This is a time consuming pig of a job so I'm not keen. On top of that the speed seems back to normal today and strava/odometer agree. I think my booster battery may not have been fully topped off yesterday. Still, the noise is certainly still much less. When I have to dismantle controller housing next I'll test the throttle outputs but until then as there is aint broke, I wont fix it !