Buying 2nd hand.

RichD1

Finding my (electric) wheels
Aug 29, 2021
13
1
When buying 2nd hand how can you tell the condition of the battery? How long do they last? The bike I'm looking at is a 2017 model and has done about 3000 miles for commuting.

Richard
 

soundwave

Esteemed Pedelecer
May 23, 2015
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i have a bosch batt which was new in 2014 and it is still working but now well down on range so they can last but id be prepared to get a replacement and account for the cost as there not cheap esp bosch Yamaha ones
 

wheeliepete

Esteemed Pedelecer
Feb 28, 2016
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What make and model is the bike? commuting usually means the bike has been used regularly which is not a bad thing for batteries. As a rough guide, if it's cheap and Chinese it's prob. close to replacement, if Bosch or Yamaha it prob. has a couple of years left in it. At that mileage check the cycle components for wear or ask what if anything has been replaced.
 

RichD1

Finding my (electric) wheels
Aug 29, 2021
13
1
Without riding is there anyway you can tell the coindition of the battery?

It's a Bosch motor and battery.
 

soundwave

Esteemed Pedelecer
May 23, 2015
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what bike is it? dealers can check the batts for charge cycles in there software.
 

soundwave

Esteemed Pedelecer
May 23, 2015
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what motor?
 

soundwave

Esteemed Pedelecer
May 23, 2015
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well if you take it to a bosch dealer they can plug it in and check for any faults and check the charge cycles.

bosch do have a capacity tester to see whats left but ask the dealer if they have this if you want this data.

imo it will cost 30-50 quid for a report.
 

Andy-Mat

Esteemed Pedelecer
Oct 26, 2018
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When buying 2nd hand how can you tell the condition of the battery? How long do they last? The bike I'm looking at is a 2017 model and has done about 3000 miles for commuting.

Richard
Difficult to test accurately, but a long, long bike ride is probably a good way to start checking, even if you only ride in large circles for a few hours, to avoid being miles from home when the battery finally is empty!
Its difficult to be accurate about the battery state, as it is a function of just how the previous owner(s) treated it. Li-ion batteries hate to be ignored for months at a time, over winter for example.
Someone selling a bike, may have simply found out that biking was not what they hoped it would be.....and the battery therefore may beyond recovering, as they may need more exercise than the rider does!
An e-bike (any e-bike) with a bad battery, is basically scrap, as new batteries are not even available for some quite recent models, or are very expensive for others.
Buying a reasonable, but brand new e-bike, is the best way to save money and problems later. We get quite a few here who have bought secondhand, and had a shock (literally!) from the battery...
Furthermore, just so you know before purchase, all mid motor bikes need extra "attention" for the chain drive, if they are to run failure free for long periods, as ALL the torque from the motor AND all the torque from the rider, all go through the same chain. A chain no different from that on any other e-bike, or normal bikes....
Whereby a front or rear motor bike, no motor torque goes via the chain. It has therefore significantly less wear and tear on the chain.
Furthermore, on most of the front and rear motor bikes, if the chain breaks (far less likely than on a mid motor), and the battery still has power available, you can ride home either without pedaling after removing the chain from blocking the wheel, or just free wheeling the pedals to make the pas sensor work for you and start the motor drive.....
All mid motor bikes, if you cannot repair/replace the chain where it breaks (at night, in the forest etc.), then you may have a long walk home!!!
Your choice.....
regards
Andy
 

soundwave

Esteemed Pedelecer
May 23, 2015
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i have had a chain snap 2 times since 2014 once where i kept reusing the power link connector which you are not meant to reuse and it snapped but made it home with half the side missing.

and the other time is when the jockey wheel exploded snapped the chain and the rear cage of the mech.

i now have a sram xx1 mech and metal jockey wheels and a new cx motor in the post :p
 

sjpt

Esteemed Pedelecer
Jun 8, 2018
2,727
2,120
An e-bike (any e-bike) with a bad battery, is basically scrap, as new batteries are not even available for some quite recent models, or are very expensive for others.
I agree with much of that post, but that is a little extreme. There are certainly some models with really difficult (impossible?) to replace batteries, but a lot of bikes use stock batteries that are not too difficult or expensive to replace. Even for a bike with expensive replacement (eg Bosch) it is still well worthwhile.

But when buying 2nd hand just assume that battery will need replacing and factor that into the cost. If you find the battery was good after all that is a bonus.
 
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Nealh

Esteemed Pedelecer
Aug 7, 2014
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West Sx RH
I agree with SW, it's no brainer one can get a diagnostic readout from a bosh dealer with the right equipment. A £50 or so charge may save a lot of grief before you buy it.
 

Gringo

Esteemed Pedelecer
Jun 18, 2013
1,306
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Northampton
I’m on my 3rd mid-drive bike (2nd Bosch) and I covered 5,000 miles on this one, it’s on its 3rd chain and 2nd cassette and chainring.
ive never had a chain failure on any ebike but I have had one go on my analog mtb :confused:
should the worst happen, I carry a chain breaker and a quick link, so I’ll never be stuck :p
 

Andy-Mat

Esteemed Pedelecer
Oct 26, 2018
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I agree with much of that post, but that is a little extreme. There are certainly some models with really difficult (impossible?) to replace batteries, but a lot of bikes use stock batteries that are not too difficult or expensive to replace. Even for a bike with expensive replacement (eg Bosch) it is still well worthwhile.

But when buying 2nd hand just assume that battery will need replacing and factor that into the cost. If you find the battery was good after all that is a bonus.
I don't disagree, but how is someone with very little knowledge and experience in buying 2nd hand e-bikes, going to work out what to buy or pay.
I have seen the letters here on Pedelec, from "beginners" caught having bought secondhand e-bikes that were basically scrap....I am sure that you have too.....
So I feel its better to err on the side of safety for anyone posting about buying a secondhand machine......though my first was secondhand (1 year old), and it lasted me over 7 years, and both it and the battery were still functioning well when I gave it to someone for nothing......as I was unable to ascertain just how much longer the battery would last, and it was an extremely expensive battery, nearly €450 the last time I checked.....
So I did not feel right in charging him anything for an over 8 year old bike, that was cheap (€799)when bought new from a large supermarket chain here..........
To my knowledge, he used it for more than a year, then I lost touch, as he moved away......
regards
Andy
 
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soundwave

Esteemed Pedelecer
May 23, 2015
11,762
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i bought my bike 2nd hand of ebay with 160 miles on it for £3500 with all receipts yet had no warranty from ebike shop where it was bought from cus he is a twat!

rrp was £5500 and had a dropper post fitted so a nice chunk off the rrp price so bought it and is still working with the original batt and motor with a dongle on it.

now just that it says it has done 3000 miles on the clock does not mean that is the real mileage as can be much higher than this if a dongle was used on the bike above the 15mph limit as screws up the odometer so could be in fact double that number and a bosch dealer wont be able to tell either just so you know.

the bearings in the motor can be replaced as long as the controller is still working but performance line bearings can sort those out and fit them if needed, nothing lasts forever.

 

matthewslack

Finding my (electric) wheels
Nov 26, 2021
6
4
I ride Shimano not Bosch, but likely the technique I use to work out how much charge I have at any time in my battery would have an equivalent in the Bosch world...

A brand new battery, fully charged, when the bike is switched on from cold, should show the range claimed by the bike manufacturer. So for my Ridgeback X2 with Shimano E5000 and 418Wh battery, that is 150km in level 1 assist (eco).

My experience with this Shimano setup is that every time I turn off the bike, and then turn it on again, it will forget how I was riding before it was turned off, and the range shown will be proportional to the Wh left in the battery.

So if I turn on and level 1 range shows as 90km, I have 90/150 x 418 Wh = 251Wh left in the battery.

With a used battery - even my fairly new ones - the fully charged range will show as a bit less than 150km. One of mine shows 146km, the other shows 143km. I interpret those numbers as a measure of the battery condition - so the worst of them is 143 / 150 = 95.3% of its original capacity.

So if you are able to, fully charge the used battery, see what the bike says, check against manufacturer's specification, and you will have a bit of an idea!

Anything less than 90% and I would go the 'buy a new battery and negotiate on price' route.