Your diabolo can wobble for 4 different reasons and there are solutions for each one of them:
- The cups are loose and you need to tighten your diabolo
- You are not using your bearing the right way, just check the black hub is where it should be
- The cups are warped and you need to give them their shape back
- The cups are unbalanced and you need to add weight to the lighter side
The Cups Are Loose
This is the most common reason and the first one to test. The fix is the easiest one too: tighten the bolts inside the cups.
If your diabolo has a fixed axle, you can test if the cups are loose by putting your hands on each cup and turn in different directions. If one or both cups move, the diabolo needs tightening. For fixed diabolo tighten the axle as much as you can without forcing too much.
If your diabolo has a bearing axle, just tighten the axle without forcing. If you hear a creaking sound stop immediately, if you force any more you will damage the axle.
Not Using The Bearing The Right Way
If you try to start the diabolo against the bearing, it wobbles violently.
When you use one-way bearing diabolo, you need to have the black hub closer to you if you are right-handed and have the black hub away from you if you are left-handed.
Try using the diabolo with the hubs facing the right way and if the diabolo still wobbles then look into the other reasons.
The Cups Are Warped
If your diabolo cups are not perfectly circular, it may be the cause of the wobble.
If your diabolo has flexible, rubber cups, you are most likely to encounter this problem. You can get rid of the warp and reshape your diabolo by:
- putting your cups in warm water, hot water from the tap is enough, no need to boil the water. Let the cups soak for 10-15 minutes
- put bowls in your diabolo cups, put your bowl upside down on a stable surface and put your cup on top
- put weight on top of them, anything will do as long as it’s heavy enough (about 1.5kg or 3.3lbs)
If your diabolo is a bearing, be careful not to put the axle in the water. It is safer to disassemble your diabolo first.
If your diabolo has hard cups, it will most likely break before it bends, so you won’t have this problem.
The Cups Are Unbalanced
If the diabolo is perfectly tightened, a weight difference between the cups might be the problem.
It can happen for example with cups of different colors. Exchanging cups between diabolos (of the same brand) is a common customization. Sometimes the weight of different colored cups are slightly different and it is enough to make your diabolo unstable.
Or one cup might have more scratches than the other.
The solution is to disassemble your diabolo, weigh each cup, and if there is a difference, you can put an extra metal washer or two on the lighter side to make up for the weight difference.
If none of the solutions work, you have a more serious problem usually involving the axle itself. You will generally have to buy another diabolo as it is difficult to find a juggling shop that sells pieces at a reasonable price, unless your diabolo is from the Sundia brand then you can order parts for your diabolo at https://www.diabolomoves.co.uk/.
This will happen a lot more with old bearing diabolos, because the axle (having multiple parts) is more fragile than a fixed axle.
