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7.2 miles
Distance
407 ft
Climb
-403 ft
Descent
440 ft
High Point
4 ft
Altitude change
130 ft
Altitude min
150 ft
Altitude start
154 ft
Altitude end
-11.6%
Grade max
20%
Grade min
3 miles
Distance climb
3 miles
Distance down
1 mile
Distance flat
In Albert Einstein's recently-discovered treatise entitled The Relativity of Mountain Biking, the first equation we see is called The Flow Equation. It is denoted by
Flow + Bike = Fun
We seek to optimize the right-hand side of the equation. In other words, have more Fun. By the iron law of equality, if we increase the right-hand side, we must increase one or both terms on the left. Since Bike is effectively a constant (we can only ride one at a time), that means we need to increase Flow if we want more Fun.
Which is precisely what this route does.
The route offers the most concentrated flow with the least required mileage to be found in the Preserve. You'll enjoy a fun climb up Switchbacks (watch for downhill riders). You'll roll through the surreal Tunnel 4. A series of ups and downs comes next, then it's a downhill run back to the trailhead. Congratulations, you have solved the Flow Equation.
Some things to note:
1. The route is geared to intermediate riders and consists of green and blue trails.
2. The route is short enough to be a lunch ride. Consider The East Ender, which is this route on steroids, if you want a longer flow ride.
3. Please bring a bell. The trails are busy, and sightlines are often limited.
Detailed Description
Flow Equation is a 7 mile popular intermediate route located near San Diego California. This mountain bike only route and has a moderate overall physical rating. This route includes 8 trails. This route climbs 407 ft with a max elevation of 440 ft then descends -403 ft.
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Stats
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Distance7 miles
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Avg time1 hr 29 min
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Altitude change4 ft
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Altitude min130 ft
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Altitude start150 ft
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Altitude end154 ft
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Climb407 ft
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Descent-403 ft
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Grade max-11.6%
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Grade min20%
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Distance climb3 miles
-
Distance down3 miles
-
Distance flat1 mile
33 Reviews & Comments
KeithFieldhammer
Fun fun fun till Daddy takes the Ripmo away!
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Trails in Route
| 984 ft | |||||
| 2,887 ft | |||||
| 2,185 ft | |||||
| 1,919 ft | |||||
| 2,710 ft | |||||
| 5,072 ft | |||||
| 1,916 ft | |||||
| 5,256 ft |
Details
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Riding area
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Primary ActivityMountain Bike
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Difficulty ratingBlue
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eBike Allowed
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Bike typeAM, XC
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Physical ratingModerate
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Trail Flow (Ridden Direction)
Trailforks scans users activity logs to determine the most popular direction each trail is ridden. A good flowing trail network will have most trails flowing in a single direction according to their intension.
The colour categories are based on what percentage of users are riding a trail in its intended direction.
The colour categories are based on what percentage of users are riding a trail in its intended direction.
- > 96%
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- > 80%
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- bi-directional trail
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The intended direction a trail should be ridden.
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Trail Popularity ?
Trailforks scans activity logs to determine which trails are ridden the most in the last 9 months.
Trails are compared with nearby trails in the same city region with a possible 25 colour shades.
Think of this as a heatmap, more activities = more kinetic energy = warmer colors.
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- popular
- less popular
- not popular
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Winter Trails
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Missing Trails
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Trails are colored based on popularity. The more popular a trail is, the more red. Less popular trails trend towards green.
Jump Magnitude Heatmap
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BC Backroad Status
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Slope Aspect
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Photos
Videos
mtb
Minimal Climbing, Maximum Fun at Los Peñasquitos Canyon
trail: Tunnel 4
16:05 | 4 | comments: 0 | favs:
Sep 14, 2026
mtb
Amflow Vs Gravel Bike, San Diego Mountain Biking, Tunnels, Best trail in SD? Avinox #mtb #emtb
trail: Tunnel 4
5:24 | 207 | comments: 0 | favs:
Apr 22, 2026
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