This trip was a blast. We started at 4,700M and biked for 45 kilometers all the way down. My girlfriend and I were different levels, but the guides could accommodate both of us. We were provided snacks and water on the trip, so we had energy the whole way. Even though both of us experienced some altitude sickness in Cusco, we both felt fine the whole way down Chachani.
The mountain biking has a nice casual (but fun) path down the roadway and a steeper "shortcut" route.
Wilmar was a great host and met us in our hotel (Sonesta Posada) the night before to go over details with us. Tito, the guide was also great at showing us (me - as my GF took the roadway down) the cool shortcuts where we could really fly. It is best to have some downhill mountain biking experience for these. Although the "shortcuts" are not the level of the Whistler bike park, they are still fun enough to get the adrenalin up. I even bailed once.
A cautionary note that even on the roadway you can get some real speed and it can be bumpy at times. My GF did not have a ton of experience, but she still did great. It would be advisable for you to have at least biked down a bumpy dirt path before.
You should do this trip for a few reasons:
1) The view is incredible.
2) You can tick off "biking down a volcano" from your bucket list
3) Might as well get your adrenaline up.
4) If you are experienced enough to go, and don't go, you will regret it.
One last note: If you are going to Machu Picchu, you should also spend some time in Santa Teresa at the Eco Quechua Lodge. (http://www.tripadvisor.ca/Hotel_Review-g3463634-d1646226-Reviews-Eco_Quechua_Lodge-Santa_Teresa_Sacred_Valley_Cusco_Region.html)
This is the best Eco Lodge you can imagine.
Paul & Tammy
If you own or manage Peru Breathtaking Trips Day Tours, register now for free tools to enhance your listing, attract new reviews, and respond to reviewers.