Fitting chainring - bosch motor!

[Jim600]

Hi all, sorry to make this a hurried first post (Ill do an introduction etc tomorrow

I'm in the process of re-assembling my 2013 haibike - I took the chainring locking nut off, using the correct tool then took off the chainring spider. Now I'm putting it all back together and noticed when placing the spider back on, that it sits quote loosely over the "bb" - There is a hexagon that the spider sits on to, it sits loosely enough onto this that it pivots maybe 10 degrees left and right. Tighten up the lockring and it stops pivoting - just wanted to check - is that right? Should there be some play in it without the lockring done up? And if so, when doing up the lockring is it best to have the spider loose/centered or pivoted to the left/right?

Hopefully someone understands what I mean! I've done dozens of normal crank sets but first time on an e-bike. Just seemed a bit odd that the spider doesn't sit snugly, don't want to risk "rounding it" when putting pressure on the pedals!

Thanks v much,
J

 

[flecc]

This is an extract from a Bosch service document that includes this removal and refit. Hope it helps:

"Put the spider on the greased seat and tighten the locking nut with the Bosch spider tool with 30 Nm (plastic lockring, thread greased), 20 Nm (plastic lockring, thread greased) or 40 Nm (aluminium lockring). Caution: Note left/fine thread! Tighten the crank with 55 Nm and put on the chain – done!"

There's a bit of ambiguity between the 20 or 30 Nm figures for the plastic lockring, probably something lost in translation. Perhaps should read 30 for ungreased threads and 20 for greased threads? However, tight would seem to be right.
.