New Bike Questions

[Marc8]

Hi

So this is my newly acquired Dawes Boost City Bike



The Few Questions that i have to Begin with are:

Battery.

Can you please tell me what the led lights are for on the side of the Battery, when i press the little red button at the bottom the leds flicker (Red and Green)



Handle Bar

This may seem obvious to some, but would like some clarification. What is the Led Meter on the Handle bar.
When the battery is in and turned ON the leds are lit up but the one on the furthest left goes off.



Final Query in this post.

When i have attached the battery and started to ride, the power decreases and the handle bar display (led) goes Blank.
I have read that this happens when a speed of 6Km is reached, but on my bike this happens after a while when pedaling at low speed and when i haven't turned the throttle

Many thanks

Marc

 

[Benjahmin]

Is the bike new or second hand? If so how old is the battery and how has it been looked after?
The leds on the battery are a voltage indicator. You say they flicker, can you give a bit more detail on that?
The 'photo of your controller isn't clear enough to see any detail.
On those all the leds light up as you power up, this is a prove of leds working. Then, if the battery is fully charged, there will be a row of leds lit, looks like your could be 5. There's usually some indication of power setting level, but can't see clearly enough.

OK so I've tried looking for a spec and they're all coming up as discotinued, so I'm guessing this is an old bike and you may have battery issues. Not the end of the world but gonna need more detail.

 

[Marc8]

Hi

Thank you Benjahmin.

I have taken some more Photos.

The bike as far as i am aware had not been used for a few months or at least since the summer. So the battery may have not been regularly used or charged. The bike was kept in a Garage along with the Battery.

The flicker on the Battery.
When i press the Red Button, the Red led lights up and then the two Green ones above the red, flicker on and Off and occasionally they remain Lit and the red one goes out. (See Photos)



The Handle bar Box.
This seems likely to be the Controller as you suggested.



There are no other functions or Buttons/Switches on the Controller, The photo with the leds lit up is when the battery is inserted and the key switched to on. There are 6 LEDs but only the 5 light up leaving the First one unlit.

Many thanks

 

[Deleted member 4366]

I wouldn't take too much notice of LEDs. I've seen many that don't light properly. If you're worried about your battery, measure its voltage with a voltmeter immediately after charging. Be aware that a voltmeter will also give anomalous readings when the battery is flat, so if the results look odd, check it against a known voltage. like your car battery, which should be around 12.5v to 13v

 

[Benjahmin]

AS D8 says, I'd ignore the leds on the battery.
With 5 lit on your handlebars it's saying that the battery is at full voltage. However this is no indication of capacity/health of the battery. Is it these leds that go out after you apply power? How is the power applied, by throttle or by peddling?
If the battery has been left for a substantial period without being charged it could be a bit 'poorly'. If the system goes dead as power is called for, this could be the BMS(battery management system) applying it's low voltage cut off.
Need a bit more descrition of whats happening.
Do get a cheapie digital voltmeter and measure the battery hot of the charger, it will say a lot.

 

[Marc8]

Hi

Thank you for your replies and thank you for your patience.

The LEDs on the handle bars do go out and the pedaling becomes harder until the lights light back up.

With regards to the power being applied. The Right handle bar has a throttle on the Grip. When this is turned, the bike moves with no pedaling, but after a while the power drops and the lights go out.



If however you just pedal, the bike becomes easier to pedal with the power on, (with no throttle applied). This continues for a longer period but the power drops and the pedaling becomes harder until the lights come back on and power is restored. (again without turning the throttle part of the Hand Grip)

I will now get a meter and check the voltage.

Many thanks

 

[Marc8]

Hi

This is the side of the battery

And this is the reading from a voltmeter.


Many thanks

 

[wheeliepete]

Sounds like you are suffering voltage sag under load and the bms on the battery is cutting the power, then turning it back on when the voltage rises again. If this is happening when the battery is fully charged, then I'm afraid it's capacity is very low and probably needs replacing.Try measuring the voltage immediately after the bike cuts out.

 

[Deleted member 4366]

The LEDs on the handlebar display give some indication of voltage. When you open the throttle, do they go progressively down until the bike cuts, or do they just all go off at once?

29.3v is a reason for hope, but doesn't give the whole picture.

 

[Marc8]

Hi

They go off all together

Many thanks

 

[Nealh]

Sounds like age has set in or capacity is on the wane, could be both. Voltage is healthy and pack is pretty well balanced though doesn't always mean a battery is full of beans.

 

[Deleted member 4366]

That's a good sign when they all go off together. If the battery were knackered, you'd see them go down as soon as you opened the throttle. From your description, the most likely problem is a faulty connection between the battery and the controller, which means either the key-switch or the bullet connectors at the controller. To eliminate the key switch as the cause, you need to bridge its wires and test to see if the problem goes away.

 

[Marc8]

Good Afternoon.

So a little update, I have been for a short ride this morning to test a few points listed above.

Before setting off the battery was at 29.3v. I rode the bike for about 1/2 mile without using the Throttle and the bike gave me some assisted pedaling.
I then started to open the throttle and after a few meters the power dropped, this time the lights went to three leds before Complete OFF and then after about 5-10 seconds all 5 came back on lit.

I checked the Voltage of the battery as soon as this happened, i stopped took off the battery and that is now reading 27.6v

Thank you also D8veh, but i have no idea on how to bridge the wires ect.

Many thanks

 

[wheeliepete]

Did you manage the return leg of your ride with pedal assist? If your loss of power only happens when you use the throttle, it does suggest to me you are suffering voltage sag, as you are asking the battery for more power than it is able to provide. To bridge the wires on the switch you will have to open the battery, 4 screws on the end, and cut or unsolder and join the 2 thick red wires on the back of the switch. If you don't feel confident to do this, you could try removing the battery, connecting your meter and then jiggle the key in the on position and watch your meter for voltage fluctuation. Also, as D8 said, check the battery connections on the controller are good and corrosion free.

 

[Deleted member 4366]

The problems normally come from bad solder joints to the switch rather than the switch itself. You can just cut the wires off, twist them together and put a bit of insulating tape over the join, but then the switch will no longer work.

 

[Marc8]

Good afternoon.

I rode the bike yesterday to work, about 2 miles. I only used the pedal assist (No Throttle) This got me to work ok.
Then when i finished my shift i cycled home (No Throttle). After about 5 mins the power kept dropping, this then happened every three - four revolutions on the pedal. The lights would drop to 3, then 1 then off.Returning to 5 again and then repeat this over again.

I checked the Voltage when i got home and it was 27.3V

I am now starting to think that this maybe Voltage Sag. If this is the case, is a new battery needed? Where can i get one?

I will however try the Faulty connector theory as well.

Many thanks

Marc

 

[Deleted member 4366]

I would use the opportunity to upgrade to 36v, which will give a bit more power and speed. Ideally, you'd need a new controller too, which would be another £40 on top of the battery. Has the dowb-tube got bottle cage fixings?

 

[Marc8]

Hi

The Down tube does have a bottle cage fixings


Many thanks

Marc

 

[Deleted member 4366]

Your motor will have no problem with 36v. I converted a pair of 24v Schwinn Tailwinds to 36v with new controllers and batteries. It totally transformed them from gutless slugs to sensible ebikes.

You can use any battery you want and fix it anywhere you want. It's only two wires.

 

[Marc8]

Good afternoon.

One more Question regarding the battery on this thread. Where is the best place to Buy a new battery.
I contacted my local ebike retailer and they told me to look on the internet, Not much help at all, they was to preoccupied trying to get me to buy a new bike.

Many thanks
Marc