Yes, if you want to. But be sure to get a larger one as he grows. Large
rats will need 11" chinchilla wheels (MJC). A wheel rat WILL get a
curved tail. Not all rats will take to a wheel, but if it does it will
use it a lot.
Beware of wire wheels as feet and tails may be injured. Sheet metal style wheels are best.
One place to order good wheels of a rat safe design is from Wodent Wheel.