As someone who’s only recently broken his first belt after more than 2 years with the same 9mm belt, I went on eBay to find an identical 280mm HTD5 x 9mm belt and found an interesting option in front of me… 10mm belts. Knowing that my 12T pulley on the motor side had some play, I decided to give it a go. Well, my 5 belts arrived today and they seem to be working great, on the same pulleys that I was using for 9mm. It just made me wonder, whoever decided that 9/12/15mm were the best options? Why those odd measurements? My brother’s board has 12mm belts and I have friends who are running 9mm and 11mm so we tested all of them, and for each 1mm added there was a small but noticeable difference in feel between each ride (the thicker, the better!).
That’s what I say!
And for electric skateboards as well. More torque transfer with increased belt coverage.
6mm, 9mm and 15mm are standard mass produced width. 12mm and any others needs to be cut by the seller to the correct width. Source
just my assumption, I think people tried to make it somewhat competible with imperial system 1/3 is about 9mm 1/2 is 12mm 5/8 is 15mm.
I couldn’t find 12mm for my size so I ran two 6mm belts side by side and it seemed to work fine. Just an idea.
I think you are dead on. they are in fact imperial measurements just sold in mm for everyone else.