McDowell Mountain Park Disaster

Day two of our trip targeted an area on the outskirts of Phoenix comprised of several conservation parcels, including McDowell Mountain Park and the McDowell Sonoran Preserve. I sampled a small portion of trails here back in 2005 on a business trip. On that trip, two events were being held simultaneously on the east side, MTB races on the race loops and a ultra-endurance foot race on other trails. At first I was told I couldn't ride that day, then the park staff said well, ok, just be mindful of the few runners still out on the course, they've been going over 24hrs. They were literally walking dead.

Anyway, I never got up into the mountains on that trip, basically just riding a big loop on the Pemberton Trail. New trails with mountain biking in mind have been built since that trip. One was Tom's Thumb. It was a grunt of a climb up either of a couple routes, then a riotous six mile, 2000ft plummet back to the car. I worked up a route from mined GPX tracks for Dave and I to try, basically a variant of a "Double Bypass" loop. Going between east and west halves of the park entails climbing over the mountain ridge in the center, and hardcore riders can pick routes that cross it in four places for a "Quadruple Bypass" ride. We had just completed a 100km ride the day before and had big things planned again the next day, so no quad bypass for us. The 40 mile route I had planned would easily give us 5hrs of abuse.

Much of the riding in the Phoenix area is quite brutal, even by New England standards. It is all rocky, quite loose, ledgy, with ample thorny flora to tear you up. And tires too. Our ride would take us over the Sunrise Trail to the east side, loop around on Pemberton, then come back up to Tom's Thumb for a final descent back to the car. Things didn't quite go down as planned.

Working our way towards Sunrise Trail, we meandered through washes and backyards. Although very bony, the trail was well maintained and had nice flow. Occasionally we popped out on ragged doubletrack. On one fast, ragged descent, Dave flatted. Like instantly, the rear tire went flat. Pinch flat, presumably. He was running Slime tubes. I warned of running tubes in Arizona when we booked the trip. Dave heeded the advice and ordered a set of UST tubeless wheels. But they've been on backorder forever and didn't come in time for the trip. I couldn't just loan him a set of my tubeless wheels either, as his Yeti uses newer through axles front and rear.

Dave climbing Sunrise (I think)

Somewhere up high, probably Sunrise Trail

Descending Sunrise

Pulling the tube out, it was split nearly 1/2 inch in two places on the inside of the tube. It did not look like a pinch flat, as it was split at a machinery mark in the tube, a defect. We tried patching the splits, but nothing will stick to a Slimed tube. Dave had only one spare with him, and I had only one with me. He put the spare in, so now we had one spare between the both of us and 30 miles to go. He upped the pressure too.

A little while later, Dave flatted again. Same wheel, different spot on tube, but similar split in tube. We tried patching again. No success at all. The glueless patches didn't work either. My spare Slime tube went in. Now we had zero spares and 25mi of rugged terrain to ride, continuing away from our vehicle. See where this is going?

After inflating all of our tires rock hard, like 50psi, we bombed all the way down into the east side, nearly 20 miles into the ride and away from the car. Ever ride Kenda Small Block 8's on loose, sketchy Arizona terrain at 50psi? Frightening to say the least. We were on the Dixie Mine Trail, when I noticed Dave was no longer in site. Not again! I turned around, only to find him futzing with his rear wheel, again. Flat. No spares. Only a couple patches left. We tried patching it, overlapping glueless patches, hoping the Slime wouldn't ooze out around them. It seemed like it held, so we set off.

We didn't get far before Dave was no longer behind me. I turned around yet again, to find him walking his bike. Our ride now turned into extrication operation.  Dave was nearly 6mi from the nearest road, which was a long drive from where our car was parked on the opposite side of the huge park. Fortunately, even though the temp was well into the 80's, he still had a lot of water and route finding to the McDowell park entrance would not be difficult. We parted ways, Dave walking east, me riding west.

I felt badly for Dave, as the last time we went on a trip, he broke a wheel about 40 miles from the car in Georgia and had to be rescued. In that trip, Brett and I still finished the full ride. But nice people brought him to town and got him fixed up with a replacement loaner wheel before we came back to pick him up. That saved the rest of his trip.

I was more worried about myself. I had to go off our planned route, taking a shorter way back to the car, but still 10 miles of sharp rocks and dangerous terrain with no spare tube and no cell phone. I decided to go up East End trail from Windmill Trail to Tom's Thumb, so at least I could salvage that from the ride. Bad choice. I vaguely recalled the topo map suggested climbing East End might be challenging. It was not only challenging, it was very difficult to hike up with a 27 lb MTB. It was a rock slide of car and small house sized boulders. Hiking progress was so slow that both my GPS and bike computer failed to detect movement at times. I have the threshold set to 0.5mph on the GPS. 1200ft of vert like this would take a very long time. For those that have hiked Tuckerman's Ravine on Mt Washington in New Hampshire, this was like that. Descending Tom's Thumb better be worth this. East End topped my list as mother of all hike-a-bikes, even bigger than the 4WD route up Mt Hopkins Alex and I did last year.

Looking down the East End trail hike-a-bike

The scenery up top was nice. Much cooler too. I passed a couple trail runners up there. Otherwise I had the whole area to myself. Now it was time to bomb back down to the car. Or so I believed. Cresting the precipice, I thought uh, oh, how does the trail up here get down to the trail down there. It looked just as bad as what I just hiked up. Well, it wasn't as bad. The segments between switchbacks were rideable, but saddle to sternum steep. I could not ride many of the switchbacks. Just too scary steep with extreme drops to the outside. You'd fall 30ft to the next switchback below if you botched some of them. Needless to say, riding by myself with no cell phone, I did not take much risk. The descent was not what I hoped for.

Approaching Tom's Thumb

Terrain up top

Phoenix from Tom's Thumb, part way down

Tom's Switchbacks

Stacked switchbacks, didn't want to go over edge here

Self portrait on Tom's descent

Further down, after the grade relaxed, speed could be run out a little. Instead of 30% grade, it was more like 20% grade. And super chunky. I was cringing the whole time, fearing slashing a tire or flatting.  Eventually I reached the car. Dave left me a series of kooky messages indicating he was dying of thirst in the desert. That meant he was doing just fine.

Much of the descent was superchunk like this

Trail angels abound everywhere.  Part way out, Dave got a ride by park staff on some kind of an ATV. Then as I pulled into McDowell more than two hours after we split up, he flagged me down in a truck of another good Samaritan. Then to top off recovering from this disastrous riding day, I spied a tiny local bike shop just outside the park entrance, "Cycle Out" I believe the name was. The owner got both of Dave's wheels going again and I bought another spare slime tube. I think Dave and I both bought our Slime tubes from Jenson online. They were junk. Seems to be either manufacturing defect or old age. They were splitting apart at marks in the tube. The Cycle Out proprietor suggested they were old. His stock was constantly being turned over, so no fear there. The tubes Dave got from the LBS held up for the rest of the trip.

I finished with 30 miles for the day, about a mile of that off the bike. That 30 miles took 4.4hrs, a testament to how bony the riding is at McDowell. We both shuddered to think what if this had happened the day before on the AZT between Picketpost and Kelvin. It would have been a real rescue situation for sure, as Dave would not have had enough water to walk out.  We were actually fortunate for this to play out the way it did. We'd live to ride another epic the next day.