Crank Arm 'Play'

fury21

I'm having to tighten my left crank arm bolts on a fairly regular basis as there's noticeable sideways 'play' in the joint, giving a clunky movement as I push down on that side.

Should there be any play there at all?

Do I just keep tightening the bolts as needed or is this something I should get checked out?

thanks.

Wooliferkins

Square taper or external bottom bracket?

fury21

Its the Alfine chainset, which I think is external bearing

mmacavity

Like this one ?
http://techdocs.shimano.com/media/techd ... 604038.pdf

or this

http://techdocs.shimano.com/media/techd ... 616019.pdf

fury21

Looks like FC-S500

Edit: Actually it looks like that answers my query

The two left crank arm mounting bolts should be tightened alternately in stages
rather than each bolt being fully tightened all at once. Use a torque wrench to
check that the final tightening torques are within the range of 12 - 15 N·m.
Furthermore, after riding approximately 100 km (60 miles), use a torque wrench to
re-check the tightening torques.
It is also important to periodically check the tightening torques.
If the tightening torques are too weak or if the mounting bolts are not tightened
alternately in stages, the left crank arm may come off and the bicycle may fall over.

thanks