It was a legal reason

According to Wikipedia:

"The City of Colorado Springs began to pave the highway in 2002 after losing a lawsuit against the Sierra Club, which sued on account of erosion damage to streams, reservoirs, vegetation and wetlands downstream from the 1.5 million tons of road gravel deposited over several decades.

The local authority paved approximately 10% of the route each year after the order. The 2011 event was the last race with dirt sections, comprising approximately 25% of the course.

Hill Climb champion Rod Millen warned at the time that paving the road would put an end to the race. However, the 2012 race saw over 170 racer registrations by December 2011, compared with 46 at the same time in 2011."

I guess that he was almost 400% wrong.

2016 Pikes Peak International Hill Climb Overall Winner

Regards,

MTF

Norma M20 RD prototype wins 95th Pikes Peak International Hill Climb with Honda engine!?!

By: MTF : June 28th, 2017-07:43

Romain Dumas wins his third Overall Pikes Peak Hill Climb title from three attempts in a Honda powered car. Considering the trouble Honda is having in F1 Grand Prix right now, that is staggering. Norma MR20 RD 2017 model Romain Dumas wearing the Mille Mig...

Congrats to him.

By: zabreg1 Mr White : June 28th, 2017-08:40

Although the race was much more fun when it was not asphalt but a dirt road.

Still can't understand why they tarmaced (is that a word?) that dirt road...

By: Arie - Mr Orange : June 28th, 2017-09:09

😒😢

I miss those days.

By: zabreg1 Mr White : June 28th, 2017-09:55

Racing of all kind used to be more fun.