Electrostatic charge buildup on unicycles

I have a new tire on my 20" unicycle. It is a 20x2.4 slick tyre (Elcat fireball) and did a ride into town today. Stopping at a traffic light i tried to lean against a metal pole and drew quite a spark. I have been experimenting with it all the way back. I can easily shock people when passing by :smiley:

Anyway i was wondering if this happened to anybody? It must be due to tyre deformation or some other form of rubbing between the asphalt and the tyre. I suspect that riding indoors in a gym produces a similar effect.

Hmm… This sounds interesting. Idiot hanging out the window of a car to film me? Poke his phone and short it out :sunglasses:

I’m no scientist… But how does this even happen? Doesn’t rubber touching the ground prevent this (And rubber-soled shoes?)

I don’t know if uni has anything to that or rather some clothing. The uni itself has nothing more than the tyre rubbing, which should not generate things like that imho.
I got lots of static in some of my sweatshirts when rubbing against my chair at work, so maybe you have something that rubs against the saddle?

Are you wearing corduroy pants? :smiley:

I never noticed static build-up before; at least not outdoors. Maybe in a gym in dry winter air.

We (Unicycle.com) have seen this before on 20" tyres. It is one of the test criteria for tyres, do they create static shock when riding. I remember at least one tyre being rejected on this criteria.


I can imagine that this is an undesired side effect. I was wearing clothing like jeans and such. The weather wasn’t even very dry or hot but the pavement was. I bought this tyre to play unicycle hockey in a gym so i am a bit worried it will be much worse there.

Rubber touching the ground prevents there from being a route for discharging. This means the electricity builds up as it is created and makes it discharge rapidly instead of gradually.

Great, where can I get one? Do they make this tyre for a 26? :wink: