Crankset rocking from side to side
Hello,
This past month I'm having an issue with my crankset on my road bike.
Crankset is a Magene p505 power meter with the chainrings/right crank arm/ crankset axle being 1 block, and left crank arm on its own. It has been working flawlessly for 20 000km.
There is play on the left crankarm even when it's freshly screwed up, the "star screw" is screwed to the max without any resistance at all. During the ride, the play gets bigger and bigger and the whole crankset rocks side to side on each pedal stroke, 3 hours into a ride big chainring is not available anymore because it ends up too much on the right.
I bought rings to put on the crankset axle between the edge of the frame/bottom bracket and the left crankarm. Now, there is resistance when i screw the "star screw" and there is no play at all when its freshly screwed, feels very secure. I thought my problem was solved, but I did a 2hour ride today and play appeared towards the end.
These are pictures of the situation at the end of the ride : https://imgur.com/a/lXNOxbB
When I screw the "star screw", I first undo the 5mil allen screw and then screw it to the max.
Do you guys have any idea what is causing the issue ?
Thanks a lot!