Front spindle bearings

Hi everyone,
This is my first post so I hope I’m doing this right. I have a 125cc Tony Extreme (at least that’s what it says on the name plate), and I’m doing the front spindle bearings. They have a different inner and outer size. Inner: 17mm ID, 37mm OD, and I can’t find any of those literally anywhere. Any help is appreciated.
Thanks,
Jacob C

Does the bearing have a number on it? Also pictures may help to see what kind of front spindle system the kart is running

The bearings don’t have any markings but I’ll send some pics of the bearings, I don’t have the spindle with me atm but I’ll send a pic of it when I can.




I had the same issue and I got mine from Comet kart sales.
Very knowledgeable people.
You can also try TS racing

“6003zz” is probably the bearing you’ll need. That’s what is in my Tony with the 17mm front hubs.

The 6003zz has an OD of 35mm, and mine had ODs of 37mm and 42mm. I suppose I could get one with a 35mm od and see if it works though.

Also what is the mobile app that can be used with this forum?

Discourse Hub:

The 40mm OD x 17mm ID (12mm width) would be a 6203-2RS.
The 35mm OD x 17mm ID (10mm width) would be a 6003-2RS.

I believe you are correct. My caliper must have been off by an tiny bit because I cleaned all the crud off the bearings and sure enough they are marked. The smaller one is a 6003z and the larger one is a 6203. Thank you all for the info, I’m sure I’ll have more questions soon. Also does anyone know of the rarity of this kart? These are the pics I have of the tag on the chassis: