in racing and you are on a SS, you NEED to be an ***** to pass people. They will understand once you pass and they look at your chain ring. It's hurts more to go slow on the SS then to carry momentum up and keeping your cadence in a good range. Just try to call it out on every pass, they might give you an extra inch to move past them. If there are people walking their bikes up, YOU have the right away, say "rider coming up" or something.
Downhill at your own pace so you don't crash but don't ride the brakes the entire way. You hands will cramp up and your speed is scrubbed off too fast. Use the back brakes to control the speed on the straight DH sections or between turns and use the fronts for braking into turns if they shape enough. Believe it or not but most XC racers are DH pusses.
I don't know how the trails are by your house, but if you can DH all the trails good at Aliso Woods, you're on good terms. Those are some GOOD DH and climbs there. Well worth the drive from here in San Diego.
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Rule #10 // It never gets easier, you just go faster.