TSDZ2 creak / click

[dgc]

Have the TSDZ2 mid-drive fitted to my mountain bike covered about 2000 mile, been great but had developed a creak which turned out to be loose crank arm(s), rather than tighten them I bought a new set of crank arms, one Bafang and one Tongsheng along with a set of new pedals. Prior to fitting I did the crank bearing update, with the new crank arms and pedals fitted, crank bolts were torqued up everything great. On a test ride a day later stopped and spoke to a neighbour during which time the mid-drive powered down so just rode the few yards back to my garage unpowered. So with no power on there is a very slight click, everything crank wise is tight, but pushing down on on the left pedal slight click, pushing down on the right pedal no click. Sound is definitely as far as I can tell coming from the crank axle area. I am going to re-torque the crank arm bolts, but can the manufacturing be that bad.

 

[beemac]

Crank arms are relatively easy to deform when loose i've found over the years - especially when I was a kid. Are you sure they're still square? Once deformed past a point they'll wobble a little even when tight.

I've also had clicks whilst pedalling because the chainring bolts securing the chainring to the spider have come loose and so the chainring shifts slightly as you pedal causing a click.

 

[dgc]

Yes, you are right, the crank arms are soft, that is why I put a new set on which meant I could also go for the better pedal position using the Bafang and Tongsheng arm combination. Being a retired engineer the tightening torque of 40nm is at a guess enough to start cold forming the square hole in the arms. Will check the chain ring bolts anyway but as the click is / was one sided think they are OK. The only other time I have had a creak / click was nothing to do with the mid-drive was from loose spokes in the back wheel, the noise seemingly being transmitted thro' the chain / frame.