Change Reaction has both machine and hand-cut trail. Compared to Cyn City, Change Reaction is steeper and narrower.
Change Reaction
Change Reaction is an expert-level one-way DH trail on the upper mountain of Park City. The trail runs from the middle of Charlie's 9K down to Webster Road just above the Midmountain Trail. It's 1.1 miles long with 575 feet of elevation loss. With a starting point of 9250 feet elevation, the expected riding season will be July through October.
Change Reaction is unique because it's an expert DH that's not part of a resort system. It offers the option of riding laps by climbing either Fat Lip or McConkey Road back up to Charlie's 9K. Change Reaction must be reached via other trails, so it's not ideal for shuttling with heavy DH-specific bikes.
Sample of the "A/B-split weave" pattern. An alternate coming from far right makes a gap jump over the trail, then banks to jump the trail again at left.
Trailhead and Connections
Looking back at the Bonanza Flat trailhead.
Bonanza Flat
Most riders will start from the big parking area on the Guardsman Road in Bonanza Flat, 1/2 mile west of Empire Pass. Go uphill across the road to the singletrack, which will take you east and uphill 0.7 miles to meet 9K where it branches away from the ridge doubletrack.
Most riders will start from the big parking area on the Guardsman Road in Bonanza Flat, 1/2 mile west of Empire Pass. Go uphill across the road to the singletrack, which will take you east and uphill 0.7 miles to meet 9K where it branches away from the ridge doubletrack.
To return to the these upper mountain trailheads, there are several options. Most will require that you descend from Charlie's 9K to Midmountain, then select a climbing trail such as Corvair, Tour des Suds, or Boulder to the east. To the west, you can take Tommy's Two Step, Three Candles, Keystone, and Shadow Lake to the 9K trail.
Heading out from the Empire Pass parking area on the westbound doubletrack.
Empire Pass
The trail can be reached through the Empire Pass parking area. Take the doubletrack west past the top of Corvair, then turn right onto 9K 0.1 miles after leaving the parking area. This is a fairly small parking lot, so on weekends you'll probably need to find another starting spot. It's 2.5 miles from Empire to Change Reaction.
The trail can be reached through the Empire Pass parking area. Take the doubletrack west past the top of Corvair, then turn right onto 9K 0.1 miles after leaving the parking area. This is a fairly small parking lot, so on weekends you'll probably need to find another starting spot. It's 2.5 miles from Empire to Change Reaction.
From the lower mountain
All routes to Change Reaction must climb to Charlie's 9K trail. First, get
to the Midmountain Trail. The most direct routes from town are Jenny's and
Mother Urban. If you're starting from Deer Valley, simply ride west on
Midmountain.
Cruising Charlie's 9K heading from Empire Pass.
Shadow Lake route: From Midmountain, take Tommy's Two Step or
Steps to the Yurt, then Three Candles, right onto Keystone to Shadow
Lake.
Above Shadow Lake, hook onto the beginning of Blazing Saddles, then fork
left onto 9K and ride 3.3 miles east.
Apex: Take upper CMG to Thaynes Road to Apex and climb to 9K.
Fat Lip route: At Three Candles, go left on Keystone. Transfer to Fat Lip. At McConkey Road, connect to Stiff Upper Lip. At 9K, go right 0.5 miles.
Corvair: Climb directly to Empire Pass from Midmountain and head west to 9K.
Boulder: Climb Boulder but fork right onto Moosebones. At the road, connect to Upper Corvair for the climb to Empire Pass and 9K.
Apex: Take upper CMG to Thaynes Road to Apex and climb to 9K.
Fat Lip route: At Three Candles, go left on Keystone. Transfer to Fat Lip. At McConkey Road, connect to Stiff Upper Lip. At 9K, go right 0.5 miles.
Corvair: Climb directly to Empire Pass from Midmountain and head west to 9K.
Boulder: Climb Boulder but fork right onto Moosebones. At the road, connect to Upper Corvair for the climb to Empire Pass and 9K.
Change Reaction Trail
Entry to Change Reaction while riding westbound on 9K.
Change Reaction is 1.1 miles long with 575 feet of elevation
change. The origin is marked with a sign on 9K at mile 3.3 from Blazing
Saddles or 2.5 from Empire Pass. When coming from the east, the entry is
0.7 miles from the origin of Black Forest and Cyn City at McConkey Road,
or 0.5 miles from the trail fork for Stiff Upper Lip.
Most of the trail is machined bench-cut. Turns are tighter and the pitch is steeper than on nearby Cyn City. The lower portion of the trail is more natural, with narrower track on loam between the trees.
Rolling into the first turn.
Looking back uphill at the main trail, with an alternate crossing as a gap jump.
Relatively quickly, you'll begin to encounter some alternate lines. In 2023, some are obvious and others are hard to spot before you've passed them. None are marked.
A couple of these alternate lines form a "weave" pattern, where they diverge then cross back over (usually by treating the main trail as a gap jump) a couple of times.
Most stunts on the main line of the trail can either be rolled or handled with a quick ride-around.
There are many high berms to put you onto your riding line.
Looking up at a log drop on an alternate line.
Although most of the descent is in deep forest, you'll cross a couple of large ski-slope meadows. Near one of these, you'll cross over Fat Lip.
As you approach the bottom, the trail has a more raw character, with loose dirt on rooty steep pitches.
The Change Reaction singletrack ends as you approach Webster Road. As it hits a doubletrack heading toward the building, find the Change Reaction to Keystone connector trail straight across the doubletrack. Climb up to Keystone, turning to the left uphill as you reach it. Climb 0.1 mile through a series of turns, then veer left on another connector, which will take you to Fat Lip. Keep left. Shortly after you cross Change Reaction, go right (instead of dropping to McConkey's Road) for the connection to Stiff Upper Lip. It will take you to 9K, where you turn right for another run.
Approaching Webster Road.
Zoomed view of the Change Reaction area.
Getting there:
Empire Pass: As you enter Park City, follow the signs for Deer Valley and Guardsman Road. Get on Bonanza Drive heading south uphill. At the roundabout, turn toward Empire Canyon (SR 224). Stay on that road for about 3.5 miles. Go through the roundabout in front of Empire Canyon Lodge and head uphill on 224. When the road reaches Empire Pass, turn right into the parking area at the top of the mountain. The 9K trail is reached via a short connector on the ridgeline.
Pine Creek/Bonanza Flat trailhead: On the Guardsman Road about 1/2 mile west of Empire Pass, turn downhill into the trailhead. The connector to the 9K trail is across the road from parking. It's around 0.7 miles up to the 9K trail, which you'll find on the opposite side of a doubletrack on the ridge.
Empire Pass: As you enter Park City, follow the signs for Deer Valley and Guardsman Road. Get on Bonanza Drive heading south uphill. At the roundabout, turn toward Empire Canyon (SR 224). Stay on that road for about 3.5 miles. Go through the roundabout in front of Empire Canyon Lodge and head uphill on 224. When the road reaches Empire Pass, turn right into the parking area at the top of the mountain. The 9K trail is reached via a short connector on the ridgeline.
Pine Creek/Bonanza Flat trailhead: On the Guardsman Road about 1/2 mile west of Empire Pass, turn downhill into the trailhead. The connector to the 9K trail is across the road from parking. It's around 0.7 miles up to the 9K trail, which you'll find on the opposite side of a doubletrack on the ridge.
Toilet at Empire Pass and Guardsman Road trailheads.
Midmountain Trail parking on Empire Pass Road:
When driving up Empire Canyon as above there's parking just uphill from the Midmountain Trail. Just after the road makes a turn to the right, there's parking on the left side of the road. Park here if you'll start your ride on the Midmountain Trail, then coast down to the trail, which is just above the turn in the road.
Riding resources:
GPS tracks (right-click and "save as...")
Park City trails (over 150 tracks)
Change Reaction area trails
Change Reaction LAPS route
When driving up Empire Canyon as above there's parking just uphill from the Midmountain Trail. Just after the road makes a turn to the right, there's parking on the left side of the road. Park here if you'll start your ride on the Midmountain Trail, then coast down to the trail, which is just above the turn in the road.
Riding resources:
GPS tracks (right-click and "save as...")
Park City trails (over 150 tracks)
Change Reaction area trails
Change Reaction LAPS route
