I've noticed there are two different size tires for the nitro sport, the 2.2 and the 2.8, i have the .15 engine
why did they make them with the different sizes?

cause traxxas is stupid. i believe they both have the same tire diameter it's just the bead that's different. the 2.8 has a shorter sidewall so they handle better in paved surfaces. i think they were created for the jato. nitro sport should have a 2.2 wheel.

You can put 2.8 wheels and tires on a nitro sport. There seems to be more tire options in the 2.8 size than 2.2, but years ago it was the opposite. Times change. It also goes to show how much of the market share Traxxas has been able to get their hands on. Almost as if they’re trying to monopolize the RTR RC car segment of the hobby. I have a nitro rustler which is very similar to the nitro sport (I had a nitro sport I converted to a nitro rustler many years ago) and I put 2.8 wheels and tires on it because my LHS didn’t have 2.2. I actually prefer the 2.8 size wheels - especially with Jato arms on the rustler chassis.

i thought it was odd to read 2 different tire sizes lol

It’s no different than buggies and truggies. Buggy tires are narrow and Truggy tires are wide. Interchangeable on both trucks. Maxx size tires and 40 series tires are both MT tire sizes, and can be swapped around too. Anything 4WD needs to the same tire size front and back.