Seems like using the battery to power a tail light and headlight would drain the battery excessively? The bike came from the factory like that (Trek Transport Plus). Im going to mount battery powered lights. The battery is at least one year old, probably two.
Trek battery with built in tail light
- Thread starter Noel
- Start date
Not at all. The power consumed by lights is a mere fraction of that consumed by the motor. I have a hugely bright light setup (twin XM-L LEDs) and the total power consumed is 20W. On your battery that would be about half an amp current draw, compared to the 15 or more amps the motor can draw.
Michael
Michael
If your problem is the loss of range, as Michael says, it won't be lights causing your problem. If the battery is two years old it may well be starting to lose some of it's 9.6 Ah capacity since it's total of 355 Wh is not very much for a long wheelbase heavy transport e-bike with a BionX motor. That will be very likely if the motor has had much use in level 4, which rapidly eats current and gives the battery a hard time.
The bad news is that BionX batteries are very expensive, the in-frame version of your 37 volt 9.6 Ah battery being £1050 last time I looked
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The bad news is that BionX batteries are very expensive, the in-frame version of your 37 volt 9.6 Ah battery being £1050 last time I looked
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That is fantastically expensive. I've just built a 36V 11.6Ah pack from top-notch NCA cells (Panasonic 18650PF) for a tenth of that cost!
I know, the stupidity of their battery prices has crippled BionX sales. On most models they've been offering much smaller capacity batteries to make them seem less expensive, but Noel's heavy cargo bike needs that largest option.
If his battery is due for replacement, it's worth him checking out the price since it's a while since I checked and they may have belatedly changed their policy.
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If his battery is due for replacement, it's worth him checking out the price since it's a while since I checked and they may have belatedly changed their policy.
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I was wondering why my battery discharged so quickly, the heavy weight of the bike and the heavy rider (200 pounds). The previous owner used it a lot at level 4 for his commute (20 mph) so he probably stressed the battery as you said. If I run it at level 2 I only get 12 miles. At 12 miles the battery level read zero but i had to continue on for another 5 miles to get home but it still had juice left. I suppose that wasnt good for the battery.
I contacted Trek to see if the battery is still available and it is. I had better be sitting down when i find out the price, ouch!
Thanks for the information!
I need to learn how to rebuild a battery, thats a tremendous savings! I also have a Giant Revive Spirit that will eventually need a battery but the battery is no longer being made. I contacted a battery rebuild service and they wouldn't do it.
I wouldn't worry about the battery reading empty quite early Noel, ageing can produce more voltage drop which shows as reading low.
Your 12 miles is very low for level 2, though your total load weight is large. In a normal bike that BionX battery when new typically gives about 18 miles on level 4 with average weight involved, and around 30 miles on level 2. As you say, all that level 4 use on a heavy bike has hammered the battery.
To be absolutely honest I don't think the Direct Drive BionX motor is ideal for a heavy freight bike, a powerful internally geared motor like a BPM/CST would be better, or possibly a crank drive unit. Both would give better economy and usually have cheaper batteries.
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D
Deleted member 4366
Guest
That's right. You can buy a whole kit with a 15ah downtube battery and a nice powerful motor for half the price of the new Bionx battery. At least then you won't have to pay another fortune in three years time, when you need another new battery.
Hi flecc,
The previous owner said that he used to go around 20 miles on level four @ 20mph. He said that it was always on empty on his way home.
Ive noticed that my mid drive Giant Revive gets good mileage and the battery is way older than 2 years so the mid drive must be easier on the battery.
Im fortunate that everything is close where I live as the battery for the Transport is weak. I don't know if I want to spend the money on a new battery,
I like the way the bike is made re. carrying stuff but I don't like the riding position, im used to a semi recumbent . Im currently looking for a Rans Hammer Truck cargo bike that is crank forward where my feet can touch the ground flatfooted. If I can find one then Id convert it to (as you have suggested) mid drive or BPM/CST. If I cant find a Hammer Truck then I might convert my semi recumbent to an electric cargo bike using the Xtra Cycle cargo conversion.
That's what i'll do when I get my next bike, save tons of money! I'll ride this one for a while and then go the better route.
Thanks!
I went another 5 miles while on empty and it still had power. The battery is fully charged now. Im going to ride it until the battery totally quits to see how many actual miles that I can ride. I'll make a note at what mileage the gauge reads empty and then keep riding until the battery quits and note the total mileage.
Yes, probably run it until the end unless i can find someone who can rebuild it at a reasonable price. I hope to go my local Trek dealer tomorrow to find out the cost of a battery just for the heck of it. Ive dealt with them in the past and they dont have much interest in electric bikes. I think that pedal assist is a great invention, esp. for someone like me and other people who have bad knees.
Yes, probably run it until the end unless i can find someone who can rebuild it at a reasonable price. I hope to go my local Trek dealer tomorrow to find out the cost of a battery just for the heck of it. Ive dealt with them in the past and they dont have much interest in electric bikes. I think that pedal assist is a great invention, esp. for someone like me and other people who have bad knees.
I just found out that a replacement battery is possibly $1,016 USD, or 659£, if the conversion i did is corrrect. I guess the price has went down British Sterling poundwise? The Trek dealer said that he's not sure if it's available. He said that he will call Trek headquarters and if it's not available he will find out if Trek can rebuild it.
Can an aftermarket battery pack be wired in to the Bionx system?
The exchange rate is very good at the moment, the dollar was about 83p to the pound when I checked that battery price. However, US goods are rarely here at the exchange rate, all too commonly they used to convert 1 to 1, so it may turn out to be far more than that £659. In any case that's still a very high price for a 355 Wh battery, even our dearer brands only charge about £400 for similar.
I don't know if the BionX uses a three connection managed system, but if your battery has only two connectors to the bike, any other 36/37 volt battery can be used instead.
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I don't know if the BionX uses a three connection managed system, but if your battery has only two connectors to the bike, any other 36/37 volt battery can be used instead.
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D
Deleted member 4366
Guest
The Bionx uses CANbus communication with the battery, so you can't use any battery, but you could re-cell it as long as you used the original BMS
On my battery are 2 large female receptacles that I assume are the charge/feed connectors and also several very small female connectors near the larger female terminals. Ill try and attach a pic later, not sure if my tablet can do that.
Re. the cost of the battery the straight dope is: $799.99. My local bike shop said that a new battery charger ($89.99) and cord ($9.99) are required in order to purchase the new battery. Thats not including shipping, which is not cheap. So the total cost is around $1,000. Expensive.