I’m assuming you have a square taper bottom bracket + crank arms?

See this answer: Square taper crankset develops play after changing bottom bracket

If you’ve been repeatedly riding with a loose crank arm it could be that it’s now damaged.

You could try tightening with lots of torque, grease on the square taper and threadlocker (e.g. blue Loctite, but in a pinch any kind of glue works) on the threads. A retaining compound (e.g. LOCTITE® 648) on the square taper is even better than grease.

If that doesn’t help the easiest, surest solution is to replace the bottom bracket and crankset. A completely new Octalink crankset (which doesn’t have this problem) can be had for less than 30€ (+ bottom bracket for <10€).

I’m assuming you have a square taper bottom bracket + crank arms?

See this answer: Square taper crankset develops play after changing bottom bracket

If you’ve been repeatedly riding with a loose crank arm it could be that it’s now damaged.

You could try tightening with lots of torque, grease on the square taper and threadlocker (e.g. blue Loctite, but in a pinch any kind of glue works) on the threads. A retaining compound (e.g. LOCTITE® 648) on the square taper is even better than grease.

If that doesn’t help, the easiest, surest solution is to replace the bottom bracket and crankset. A completely new Octalink crankset (which doesn’t have this problem) can be had for less than 30€ (+ bottom bracket for <10€).

I’m assuming you have a square taper bottom bracket + crank arms?

See this answer: Square taper crankset develops play after changing bottom bracket

If you’ve been repeatedly riding with a loose crank arm it could be that it’s now damaged.

You could try tightening with lots of torque, grease on the square and threadlocker (e.g. blue Loctite) on the threads. If that doesn’t help it’s probably easiest to replace the bottom bracket and crankset. A completely new Octalink crankset (which doesn’t have this problem) can be had for less than 30€ (+ bottom bracket for <10€).

I’m assuming you have a square taper bottom bracket + crank arms?

See this answer: Square taper crankset develops play after changing bottom bracket

If you’ve been repeatedly riding with a loose crank arm it could be that it’s now damaged.

You could try tightening with lots of torque, grease on the square taper and threadlocker (e.g. blue Loctite, but in a pinch any kind of glue works) on the threads. A retaining compound (e.g. LOCTITE® 648) on the square taper is even better than grease.

If that doesn’t help the easiest, surest solution is to replace the bottom bracket and crankset. A completely new Octalink crankset (which doesn’t have this problem) can be had for less than 30€ (+ bottom bracket for <10€).