I have a Trampa board which has your typical grub screws to keep the pulley on the motor shaft. From day one, the grub screws come lose and make a clicking sound. It takes about an hour on each motor to retighten the grub screw, but they come lose with a few miles. There has to be away to stop this from happening? I put the last grub screw on so tight that it stripped, but it still came loose. Frank from Trampa mentioned that you can glue them in. Do you use superglue?
I had a problem with a loose torque boards motor mount, and I used JB Weld and it solved the problem perfectly. The only problem with this is that it is a permanent way of doing this.
You can use thread lock on the grub screws or as a permanent solution use bearing loctite to hold the pulley on the shaft. Plenty of threads discussing how this works.
Since those pulleys wear out quickly on an mtb, I don’t recommend a somewhat permanently or difficult to service solution.
Did you use Loctite 243 on the grub screws?
I had 8 motors so far and except 1 I always had/have problems with keys and keyways in combination with pulleys/gears. Often key and keyways are not one unity and it wiggles, that’s your clicking sound and that’s why the grub screw get loose. Find out if the keyway of the motor shaft or of the pulley is too big and add something self-adhesive on the key on that spot. I used kapton tape and fishpaper according to the needed thickness, it works perfectly and no more movement of the pulley.
Also don’t use an evil standard allen key for grub screws, I stripped so many grub screws even with new allen keys but since I use Hex Plus no more stripping. Also don’t tighten them too much and use Loctite 243.
If this doesn’t help then dremel a flatspot on the motor shaft to support the grub screw.
mate, this is awesome advice, thank you! I will do all of the above!!!
Kudos to you for just mentioning that in a nice neutral way
Here’s a link to a bit of chat on the subject.
Since they only make them in certain lengths, they are often too short and don’t engage enough threads.
Advise getting a longer one, and file or grind it down to fit perfect (make it pointed).
Also, use black oxide set screws as some stainless steel fasteners are a fair bit softer, like brie almost.