I recently ordered 1.5 slicks to replace my city commuter 2.1's. It is a hardtail mountain bike. Only 1 came in the mail but I decided to put it on anyway and try it out (rear). Today I already noticed that Im increasing in speed a pretty good amount, even when pulling a trailer. I know that on the rear it plays the biggest part since most of the weight is on the tail. So how much does the front tire plays in terms of helping speed? Or does the front only effects handling?