An interesting article from Vassilis Zafiris about mountain bike. Looks like this guy really knows his passion!
There are two main reasons. 1st when there is a lot of tension on the chain (caused by pedaling hard) the front Derailleur by its nature has a hard time pulling the chain off of one chain ring and onto another, and so often it can’t complete the shift. Also gear shifts both front and rear happen much quicker when the crank is spinning lightly, but not slowly. The 2nd reason is that this added tension while shifting stresses the whole drive train causing premature wear to the parts. What this means practically is that riders have to plan ahead and shift to a lower gear before they are halfway up the hill and aren’t able to let off pedal pressure to make a smooth shift.
Be controlled, smooth and precise in your action and use the counter steer to bring your bike to the outside of the trail as you enter into a turn. This action widens your cornering arc and allows you to carry more speed. It’s generally a smoother trail on the outside as well.
Ride around the top or bottom of bumps into and through corners. It’s smoother faster and more energy efficient.
Once you’ve entered the corner, position your body weight toward the front of the bike. This position keeps your center of gravity low on the bike. This stylized position is achieved by bending your elbows to act as suspension and bringing your chest toward the handle bars and stem. This assists the bike to turn sharply and brings extra traction to the front wheel.
As with your road bike when you stop pedaling in a corner your outside foot should go to the bottom of the pedal stroke, your inside knee swings into the corner.
Inside shoulder drops.
Outside elbow rises.
Bring your head and chest toward the handle bars.
Bum off the seat allows you to turn your hips in the direction you want to go.
Lean into the corner.
Lower your center of gravity. Think snow skiing. Mountain biking is same. It’s like carving a good turn on the snow.
Steep uphill riding position is similar to the cornering position. Bring your head and chest toward the handle bars by bending your elbows. Combined with sliding your butt forward on the seat keeps the bike tracking in a straight line and stops the bike from wandering across the trail. This keeps the front wheel down on the ground as you power into the pedals.
Remaining seated going uphill keeps maximum traction to the back wheel and keeps your pedaling technique smooth and efficient
Keep your knees pointing down the track to where you want to go. Let go of the seat with your inner thighs allows the bike to pivot underneath you.
Stand up on your pedals as soon as you are rolling downhill. Dominant foot forward and slightly up from a horizontal position. This makes the front of the bike light and lets the front wheel aquaplane over the bumps.
Roll down through your heels when standing up. This evenly distributes your weight onto both legs and into the pedals. It allows you to have your weight further back on the bike and apply more back and front brake when your travelling in a straight line.
Thank you Vassilis Zafiris for your input.