Tire not fitting on wheel.

Hi everyone,

I’m assembling a wheel and running into an issue where the tire and tube aren’t fitting properly on the rim (photos attached). I reused an old tube from my previous setup, and it seems to be spilling out after inflation. While I can’t see exactly what’s happening inside the tire once it’s inflated, it seems like the tube isn’t seating correctly in the rim, which may also be causing the tire not to sit evenly.

Here are the components I’m using:

Wheel: Wheel Master 700c Rear Wheel – Quick Release, 36H, 8-Speed
Tire: Schwalbe Marathon GreenGuard 700x32c
Tube: Bontrager 700×28–32c
Rim tape: 700c

I’d really appreciate any guidance on what might be going wrong and how to fix it – whether it’s a sizing issue, installation step, or something with the tube itself.

Thanks in advance for your help!