TSDZ2 how freely should the crank arms be able to turn?

[millstheskills]

TSDZ2 has just arrived. Took it out the box and tried to spin the chain ring by hand in the direction it would normally travel and it felt stiff. I can turn it ok but it wouldn't continue moving after I stop pushing. Slipped a crank arm on and tried forward pedalling and back pedalling (by hand) and same in both directions. I can move it ok but it's not exactly low friction. Is this to be expected? I know that these kits are not as free spinning as having no kit but this is stiffer than I was expecting. Does it behave differently powered up?

 

[anotherkiwi]

TSDZ2 has just arrived. Took it out the box and tried to spin the chain ring by hand in the direction it would normally travel and it felt stiff. I can turn it ok but it wouldn't continue moving after I stop pushing. Slipped a crank arm on and tried forward pedalling and back pedalling (by hand) and same in both directions. I can move it ok but it's not exactly low friction. Is this to be expected? I know that these kits are not as free spinning as having no kit but this is stiffer than I was expecting. Does it behave differently powered up?

You need to run the motor in - say a couple of hundred km.

 

[millstheskills]

What is being "run in" though? I didn't think back pedalling or pedalling without the motor running actually turned the motor.

 

[anotherkiwi]

All motors are a little stiff out of the box. Once you have used it for a while it will free up. Some are stiffer than others - my GSM turns freely now but didn't when I first got it.

 

[harrys]

My new, out of box TSDZ2 is also quite stiff. We'll see when it gets installed next year.

 

[millstheskills]

Update: It's fitted and feels a little better. When legs are pedalling with no assist it's hard to feel the drag although I'm sure it's there. Best to just fit it and not worry too much about it I think, seems to perform very well and quiet with assist on.

 

[g_827018]

I had the same concern when I got mine. However it was fine.

 

[anotherkiwi]

Update: It's fitted and feels a little better. When legs are pedalling with no assist it's hard to feel the drag although I'm sure it's there. Best to just fit it and not worry too much about it I think, seems to perform very well and quiet with assist on.

The theory says < 5% drag, for some that is too small to notice. I would say the GSM adds about 3% extra drive chain loss when pedalling unpowered but on such a heavy bike it is really negligable.