I have a 6 wire throttle on my ebike and wanted to have a backup 6 wire throttle for it on hand just in case of accidental breakage. The manufacturer doesn't sell replacement throttles, so I ordered a generic 6 wire throttle from amazon. It operates the bike correctly, but something in the new throttle is drawing down the battery on top of the energy expended by the hub motor. I'm only getting about 60% of the usual range on a charge, and even just while parked there is evidence of a load on the battery that is discharging it, as seen in the LED display. I have checked the wiring carefully and I don't believe there is any mismatch on the 6 different wires between the original and generic throttles. Any other thoughts appreciated!
throttle replacement problem
- Thread starter J_T
- Start date
How many watts does your system usually take? How many Ah or Wh is your battery?
If you are losing 40% of that capacity from an extra load, that's very high, so it could not be directly thru the throttle unit (the wires would probably melt).
The only thing I can imagine causing it is the throttle has a higher-than-normal "off" voltage, so it is still always running the motor even when no throttle is applied. If you lift the driven wheel offground, does it start spinning?
If you are losing 40% of that capacity from an extra load, that's very high, so it could not be directly thru the throttle unit (the wires would probably melt).
The only thing I can imagine causing it is the throttle has a higher-than-normal "off" voltage, so it is still always running the motor even when no throttle is applied. If you lift the driven wheel offground, does it start spinning?
Exactly! yes i have the multi-meter. All I can think of to try so far is pin to pin resistances between the various throttle elements. Most of the resistances are infinite as expected. The finite resistances are roughly half of what they are in the original throttle, but they are all still in the 10-kohm range.
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So it's 7.5 Ah, 350W motor. Exactly as you say, it's a huge amount of energy to just disappear like that. There is no wheel motion with zero throttle, as I had tested the new throttle at first by lifting the wheel off the ground.
Sorry of course you are right, it's got an LED for battery level, and a switch button which latches the throttle voltage at the controller so you can release the throttle and cruise. There is a separate power on/off switch which also controls the lighting, I haven't messed with that at all.
AussieRider
1 kW
G'day J_T
Could be just the battery gauge, say 48v gauge on a 36v system.
AussieRider
Could be just the battery gauge, say 48v gauge on a 36v system.
AussieRider
My battery is 48V and the throttle I ordered was alleged to be for 48V. But there's nothing on the throttle to indicate 36 or 48 so I suppose I'd have to test it with a power supply voltage to be sure.
Chalo
100 TW
Simple battery charge indicators are so random, uncalibrated, and unreliable as to be useless. Instead, I use a either a display that shows me battery voltage, or else a simple lighted voltmeter.
Indeed, I was surprised to find out how primitive my ebike was in many ways, not just the battery voltage indicator. It's my first one after 30 years of riding mountain and road bikes where the products have been refined into a high state of maturity and general excellence by ruthless market competition. Although I have mentally 'calibrated' the indicator after dozens of rides such that it is at least partially useful, an accurate readout is obviously the simple and correct way to go. I will look into this as a future modification.
For my purposes I'd be happy just to know the voltage at the start/end of a ride. Although I am intrigued by how long it can take the voltage to recover after stopping. Will have to read up on that at some point, I guess that gets into battery chemistry.
Pick up the battery positive signal and ground from the wires going to the throttle and connect them to one of these. They are two wire, so only need the battery inputs (a lot of meters require a lower voltage supply, plus the battery inputs).
Awesome, i'll put this on my next amazon order and have a go at it.
docw009
1 MW
You wouldn't expect a LED voltmeter to pull much current, but some do. Let's say it pulls 10 ma, which is .01 amp. In 24 hours, that's .24 amp-hour. In two days, you;re down .5 AH. That's why most of these throttles with meters use an on/off switch.
When I attach a handlebar voltmeter to my ebikes, I put them on a switched battery line. Same for those handlebar mounted USB adapters,
When I attach a handlebar voltmeter to my ebikes, I put them on a switched battery line. Same for those handlebar mounted USB adapters,
Good to know, thanks!
