Sometimes a belt slips even though tension is fine - without any noise.
The belt gets glazed, especially the cheapo belts. No matter how much you tighten it, it still slips.
Replacing it with a new Gates belt may be a good idea - at least you'll know that isn't the problem.
Have a close look at the pulleys too - a slipping belt burnishes them to a pretty polish - pretty is too smooth to grip. A combination of a slick pulley and slick belt may be all it is.
Try putting a little bee's wax, violin rosin, or store bought belt dressing on your belt as it is, if it makes it "less worse" that's probably it. Those things won't last, so it's a test, not a cure.
The belt gets glazed, especially the cheapo belts. No matter how much you tighten it, it still slips.
Replacing it with a new Gates belt may be a good idea - at least you'll know that isn't the problem.
Have a close look at the pulleys too - a slipping belt burnishes them to a pretty polish - pretty is too smooth to grip. A combination of a slick pulley and slick belt may be all it is.
Try putting a little bee's wax, violin rosin, or store bought belt dressing on your belt as it is, if it makes it "less worse" that's probably it. Those things won't last, so it's a test, not a cure.