OK...this will probably sound stupid, but here goes...

We had our first 'cross this weekend. I did the shoe polish thing on the tires. The tires never rolled onto the actual sidewalls, but they did roll over onto the tread shoulder on the front tires. Since I thought the tread shoulder was actually part of the tread (flatish surface or contact patch with no lateral load), I didn't add any air. As a result, I fought a car that plowed all day during the Novice School.

The following day, before the actual event, I added about 2 pounds to each front and the car handled much better. Also, the shoe polish showed the tires weren't using nearly as much of the tread shoulder as they had before.

Now, which of these was my mistake? Should I have added air during the school and helped the push? Or, is the idea to use all of the tread...including the tread shoulder?

Confused...

todd