TSDZ2 Crank fell off - what spec for replacement nut?

Gavin

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May 11, 2020
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Hairon linked in post #14...
Note: Please turn on the power switch when you charging this battery pack.
Interesting. I'm assuming the BMS needs power to balance the cells whilst charging, hence the requirement to turn it on.

I wonder why mine charges when it's turned off. I'd better read my instructions....oh wait, I never got any!
 
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not dave

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Mar 29, 2020
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Unfortunately the power position makes no difference now, no light on the charger no matter what.

What chargers are recommended? Is there any benefit on getting a more expensive charger apart from increased amps / charging speed?
 
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not dave

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Mar 29, 2020
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Those battery charge indicators aren't always reliable. Multimeters don't (usually) lie...
It has been working fine. I think it quite a coincidence if the charger light stopped working at the same time that the battery lights went out of calibration.
 

Nealh

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Aug 7, 2014
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Before deciding if the charger is no good, you have to check the chargers out put connector with a meter. If it is a 36v charger it should read about 42v.
 
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not dave

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Mar 29, 2020
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Before deciding if the charger is no good, you have to check the chargers out put connector with a meter. If it is a 36v charger it should read about 42v.
Unfortunately I don’t have a meter.
there is a light on the charger that is no longer lighting up indicating that the charger is dead. But appreciate this is not conclusive.
 

Pedant peddler

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Jun 1, 2020
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Unfortunately I don’t have a meter.
there is a light on the charger that is no longer lighting up indicating that the charger is dead. But appreciate this is not conclusive.
It may be worth buying a meter, Amazon (prime)£7.99 - https://www.amazon.co.uk/Mercury-600-101UK-Handheld-Multitester-Multimeter/dp/B00LEHK23I/ref=asc_df_B00LEHK23I/?tag=googshopuk-21&linkCode=df0&hvadid=231965104222&hvpos=&hvnetw=g&hvrand=904304744606292708&hvpone=&hvptwo=&hvqmt=&hvdev=m&hvdvcmdl=&hvlocint=&hvlocphy=1007341&hvtargid=pla-423183568457&psc=1&th=1&psc=1
Or Screwfix.com £9.99 https://www.screwfix.com/p/lap-mas830b-digital-multimeter-600v/75337?tc=JB3&ds_kid=92700055262507126&gclsrc=aw.ds&ds_rl=1244066&gclid=Cj0KCQjw0YD4BRD2ARIsAHwmKVnLhkM012SBJkwUrTxqobCgI40kEghDJgSTXTQt8rdk-OdB5FX4KyMaAnbSEALw_wcB
either would be suitable. The charger you linked appears suitable. More expensive chargers are likely to be more reliable though not necessarily any better at charging. I have the same battery and charger, happy to assist if I can.
 
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not dave

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Mar 29, 2020
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Thanks. Charger has arrived and my battery is now fully charged, so issue is definitely with the original charger.
Is there much benefit from getting a smart charger? Is there much benefit from keeping the battery charged at less than 100% if it is not being used for longer periods?
 

vfr400

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Jun 12, 2011
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Interesting. I'm assuming the BMS needs power to balance the cells whilst charging, hence the requirement to turn it on.

I wonder why mine charges when it's turned off. I'd better read my instructions....oh wait, I never got any!
It's not nearly as complicated as that. Imagine a row of buckets, each with a small hole drilled in them at the same height. You can fill all the buckets to a different height, but any that are filled to above the hole will drain down to the level of the hole, so end up with the same level. Any below the level will stay where they are, but if you come along and put another sploosh in each, eventually they'll all be level.

That's how your cells are balanced. Instead of water, it's electric charge, the height of water is the voltage and the holes are bleed resistors that are opened when the voltage goes above a threshold value of about 4.17v.
 
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Nealh

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Aug 7, 2014
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Thanks. Charger has arrived and my battery is now fully charged, so issue is definitely with the original charger.
Is there much benefit from getting a smart charger? Is there much benefit from keeping the battery charged at less than 100% if it is not being used for longer periods?
Did you check the for an internal fuse or check the plugs fuse ?
One reason why a simple £5 meter is an essential item to have.
 

not dave

Pedelecer
Mar 29, 2020
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Did you check the for an internal fuse or check the plugs fuse ?
One reason why a simple £5 meter is an essential item to have.
I have checked the plugs fuse by using that cable on my laptop charger, but haven't checked for an internal fuse in the power block. If i get chance i may try and open it up to look inside.
Thanks for the multimeter advice, will pick one up form Screwfix when i am there next.

PS, is there any benefit on getting a 'smart charger'
 

Nealh

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Aug 7, 2014
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PS, is there any benefit on getting a 'smart charger'
No because they don't carry out balancing, only a bms or manual intervention can balance cell groups.

If one wants to limit charging voltage you need a smart bms for the battery to guarantee balancing is met, though good cells should remain in balance if you manually charge to lower voltage. To do this one needs to be able to recognise tell tale signs of battery imbalance as well as knowing your batteries characteristics in use.
 
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not dave

Pedelecer
Mar 29, 2020
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Thanks. Is it not beneficial to charge to 80% or less when you dont need the capacity and charge to 100% occasionally to ensure cells are balanced?
 

not dave

Pedelecer
Mar 29, 2020
75
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Regarding the TSDZ2 crank, what spec is it? I’m passing a few bike shops this afternoon but don’t have the crank with me...
 

BikeSnail

Pedelecer
Aug 6, 2021
32
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BUMP

Could we pls have an update on the OPs crank arm situation? I’ve done 50 miles on my newly converted bike with TSDZ2 and the left crank arm is coming loose constantly :)
 

peter.c

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Apr 24, 2018
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thurrock essex
Its a design fault of this motor some lh pedal arms are poorly cast, Loctite and nip nut up do not over tighten as the thread strips had to replace arms with bafang or shimmano steps versions
 

BikeSnail

Pedelecer
Aug 6, 2021
32
9
Its a design fault of this motor some lh pedal arms are poorly cast, Loctite and nip nut up do not over tighten as the thread strips had to replace arms with bafang or shimmano steps versions
Thank you. I will try to tighten with a better tool but if unsuccessful in the long term I will try different crank arms.

Does damage from riding with loose crank arms (aside from inconvenience of retightening) affect arms only or motor as well?

Wondering what the risk is in holding off a little longer…
 
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peter.c

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Apr 24, 2018
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thurrock essex
The steel shaft [motor] is a problem if it has damage to the square taper, its a new shaft full motor strip
The thread 8mm strips out if abused , have re-tapped and used a longer bolt
 

not dave

Pedelecer
Mar 29, 2020
75
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Hi, it seemed that the crank arm was of a softer metal than the shaft. When it loosened the damage was done to the inside of the crank arm meaning that after re-tightening it constantly became loose again.
I have found these are good hex keys for tightening:-

 

BikeSnail

Pedelecer
Aug 6, 2021
32
9
Hi, it seemed that the crank arm was of a softer metal than the shaft. When it loosened the damage was done to the inside of the crank arm meaning that after re-tightening it constantly became loose again.
I have found these are good hex keys for tightening:-

Thank you for the update. I hope you are still enjoying your motor!