I am going to buy Mud Light tires for my Suzuki Eiger 400 auto. These are my current wheels. 25 8-12 in from 25 10-12 in rear i know 27's will fit but will a 27 9-12 fit my rim?

 

yea they will, the first number is the tire height which has nothing to do if it will fit or not. The second is the width of the rim, so a 1 inch winder tire should fit just fine, and the third number is the height (rim), which is the same as stock so that tire should fit fine on the rim.

 

I have 26x9x12 on my Eiger and they fit fine. 26x12x12 in the rear. No problems.

 

I have 26x10x12 on the front and 26x12x12 on the back. I didn't mount them myself I took them to a tire dealer. No problems.
MudLites are great!