I just rode up Pikes Peak a week ago. I brought my hybrid bike with me. I came directly from Michigan so I was not used to the altitude.
My advice is to take your time and ride slower than you feel you need to. You'll make it.
For a flatlander like me, breathing above 12,000 feet was hard. I just took my time and took many breaks.
I burned through my brake pads on the way down. So be careful with that. You gain speed very quickly.