Pumping For Speed and Control

How to jump a mountain bike

Steep Terrain

Handling rock gardens

Switchbacks

Drop-offs

Your pedal movement rotates the crank arms, which turn the chain rings, which drive the chain, which rotates the rear sprockets and ultimately the rear wheel and propel you forward. You have three chain rings on the front and 7-9 gears on the rear sprockets (depending on whether your bike has a 21, 24 or 29 speed drivetrain). Different combinations of the front chain rings and the rear sprocket gears will make it either easier or harder to pedal, depending on terrain elevation and surface. The front and rear derailleurs do the job of shifting the chain to different gears.

The chain rings (also called “crank rings”):

Shifting the front chain rings is done using the left-hand shifter.

The smallest ring (the innermost one) is the slowest, easiest to pedal and used to climb or riding in rough or difficult terrain (sand, for example). The middle chain ring is harder to pedal than the smallest ring, but using the middle ring gives you choice of the full range of the rear sprocket. It is usually optimal to choose the middle ring if you are cycling on level terrain. The largest gear (outermost one) is the most difficult to pedal and should be used for going downhill at higher speeds.

The rear sprocket:

Shifting rear sprocket gears is done using the right-hand shifter.

You should have 7,8 or 9 gears on your rear sprocket. The higher numbers are more difficult to pedal, and vise versa. When riding in a terrain with variable elevations or surfaces, it is usually best to use the middle chain ring and use the rear sprockets to fine-tune your gear choice.

It is important to avoid “extreme gear” combinations (also known as “cross chain” combinations) which put the chain at a too large an angle from the frame. Therefore, do not put the chain on the smallest rear gear when you have it on both the largest chain ring and largest rear gear, or vise versa. The middle chain ring will give you the full rear sprocket range.

Shifting technique:

As a general rule, you should shift “before you have to”. This means that you should not wait until you get right to the section that requires shifting (difficult climb, fast descent , sand, etc), but rather you should shift early and before you actually need to shift. Anticipate the optimum shifting point in advance and make your choice of gears when you are still on easy terrain. Shifting when or after you get to the difficult section will strain your muscles and your drive train.

If you have to shift after the optimal shifting point (after you actually enter the difficult section), it is best to shift when there is least tension on the chain. To do so, pedal hard once to gain some momentum, then shift right after the power pedal stroke.

It goes without saying that it is important to keep your drivetrain components in good working order (derailleurs, chain and sprockets clean and properly lubed).

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Picture source

Basic technique:

Sandy trails can vary in the thickness, type and consistency of sand. On trails with thicker sections of loose sand, you should focus on controlling your front wheel and throwing more of your weight on your rear wheel. It is important to keep your front end light so that it doesn’t dig into sand and keep your rear firmly planted to maintain traction. Use a low gear and keep your pedal movement consistent and maintain your momentum. Limit handlebar steering (in deep sand you will easily loose traction at the slightest movement of the handlebar) and try to change directions using your own weight instead. In really thick sand sections, you might need to stand and pedal hard. It is usually best to gain speed on harder terrain and try to” float” your bike over sandy sections.

Sand uphill, sand downhill:

If you encounter sand going uphill, you need more speed and momentum. If the thicker sections are on your way down, you will need to focus on traction and bike control while throwing even more weight on the rear end.

Bike setup:

Trails with deeper, thicker sand require wider tires (such as the WTB Motoraptor 2.4) and lower tire pressure. On trails with light sand on a harder surface, a narrower tire can be an advantage since it will slice through the light sandy surface and allow you to push more on the harder surface below. In Egypt, most trails involve a variety of rock, sand or a mix of both, so your best bet is to run wider tires full-time. If the trail involves a lot of thick sand, it might also help to lower your saddle a few centimeters.

If you find yourself frequently plowing in deep, loose sand more than the usual, you might consider getting a “fat bike” with over-sized tires (3′+) and a frame and fork to accept them, such as the Surly Pugsley.

• Your torso should be neither too outstretched to the front (as if you are reaching for something), nor too upright.
• There should be a slight bend in your elbows.
• Your grip on the handlebars should be strong enough for adequate control, but not too strong so as to fatigue your forearms.
• Keep your body relaxed and your knees and elbows loose. At the lowest point of the crank movement, your leg should only be slightly bent (adjust your saddle height accordingly, preferably to be level with the handlebars).
• Keep your head up and look ahead of you, not at the front tire (or the back tire of the rider ahead of you) or to the sides. Your bike has a tendency of going where you are looking.
• Pedal to an easy rolling speed, then stand and coast. The crank arms should be at the 3 and 6 O’clock positions (parallel to the ground), your knees slightly bent and body loose and ready to absorb bumps.