MOUNTAIN BIKE ROCKRIDER ST 100 - BLACK

The recommended average tyre pressure is 2.5 bar. To be more exact, the ideal tyre pressure is determined by the weight of the user. Inflating your tyres in accordance with your weight will help you strike the right balance between performance and the ability of the tyres to avoid punctures and the pinching of the inner tube. You'll find your ideal tyre pressure in the table on the walls of your tyres. If you're looking for more grip, you can reduce the pressure by 10% but without dropping below 2 bar (the minimum recommended pressure). On abrasive terrain, however, this will increase the risk of punctures. You should check the pressure of your tyres regularly.

Your handlebar is set in the highest position to help keep your back raised, which is the most comfortable position for riding. For improved aerodynamics and more effective pedalling, you can lower your handlebars to lower your body. This will cause you to lean forward and adopt a racing position. Follow the steps in this video to move the headset spacers below the stem and lower the handlebars on your bike.

Your ST 100 bike frame is fitted with a quick-release lever. Stand next to your saddle. Tilt the quick-release lever to unlock it. Pull the saddle up or push it down to bring it level with your pelvis. Tilt the lever again to lock it. To make sure you get it right take a look at our tutorial video.

Your U-FIT fork has 1 single wheel for adjusting the stiffness. Turn the wheel clockwise or anti-clockwise to increase or decrease the value displayed in the middle of the wheel, until you reach your personal weight. Your fork will be perfectly adjusted and customised. 

There's no need to bed in your V-brakes and pads. You should know, however, that when the pads come into contact with the black trim on your rims for the first time it will make quite a noise. Don't worry, though. As you use your bike and apply the brakes more and more, a fine film of rubber will form over the rims and the noise will gradually disappear.

V-Brake pads are available as spare parts. To change them, simply follow the steps in the video. 

Your ST 100 mountain bike has been designed to help you break new ground on your first forays into mountain biking, thanks to specially adapted V-Brake technology. Unfortunately, you can only fit your bike with disc brakes if you change the fork (for the front brakes) and frame (for the rear brakes).

Your ST100 mountain bike is available in five sizes, from XS to XL. With the smaller sizes (XS and S), fitting accessories such as the stand, mudguards and child seat may prove difficult. We therefore recommend that you fit your mountain bike with the following accessories. We guarantee they are 100% compatible.

We recommend you use the 500 Adult chainstay stand.

We recommend you use the 700 mountain bike front mudguard.

We recommend you use the 700 mountain bike rear mudguard.

Use the Flash mountain bike rear mudguard: it's easier and quicker to fit.

Use the Flash mountain bike rear mudguard: it's easier and quicker to fit.

We recommend female riders change the saddle for an ergonomic 500 women's sport saddle, which is better suited to their body shapes.   

You need to drink water when you're cycling: we recommend the 550ml bottle.  You'll also need a bottle cage to keep your water close to you.   

Use the 500 bottle cage to keep your water bottle handy.

For your family outings choose the Polisport GROOVY child bike seat - rack mount.

We recommend you use the 500 foot pump.

There’s always a risk of picking up a puncture when you’re out and about on your bike, which is why you need some puncture repair spray. The spray fills the inside of the tyre with foam, allowing you to get back home. 

The 500 saddle cover offers extra comfort.

This 0.5l saddle bag is easy to fit and is ideal for carrying all your kit: multi tools, puncture repair spray, etc. 

For people who need to stay in touch. The 500 smartphone holder lets you fit your phone to the handlebar.

We recommend the 300 bike rack for carrying your ST 100 mountain bike, whether you're cycling at home or on holiday.

Your suspension fork operates best when the temperature is 5°C and over.

Below this temperature, the suspension can stiffen and even lock up, but without suffering damage.

It will start to function normally again when the temperature rises above 5°C.

If you detect a fault, however, or you are not sure if your fork is in good condition, take it to your nearest DECATHLON workshop and have it checked straightaway.

There are one or two things you can do to make your fork "softer":

1. Adjust the stiffness: check the section "ADJUSTING THE STIFFNESS OF YOUR FORK"

2. Do some basic maintenance: using a simple oil can. Squirt some oil on the pivots of the fork and move it around to work the oil into the blades.

3. Have the bike fully serviced in a workshop.

 

It's a sad fact of cycling that everyone gets punctures. And it doesn't just come down to what type of tyre or inner tube you use.

That said, it's not normal to suffer punctures over and over again. If you do, then there are several possible reasons:

- The wheel has not been assembled properly in the factory and a spoke keeps piercing the inner tube.

- A substandard tyre or inner tube.

- A badly repaired puncture or a foreign body (thorn, piece of glass, shard of metal, etc) stuck on the rim or in the tyre.

It's important to check that there aren't any foreign bodies in the tyre and rim.

 

Don't know how to put a tyre on or take one off so how are you going to repair or change an inner tube?

The simplest thing to do is not to touch your wheel and use a can of puncture repair foam as a temporary solution: Screw the end of the tube on to the valve of the punctured tyre (with the valve pointing down) and press down to inject the foam. The tyre will regain its shape and hardness, allowing you to get home.

There are several things you can do to ensure your front gears shift properly:

1. Check the position of the housing ends:

1a. Housing ends that are out of position can obstruct the derailleur cable when it is being pulled and prevent the gears from shifting smoothly.

If a housing end is out of position, push it back into place.

1b. If the derailleur doesn't move even when the gear shifter is operated, then the cable and the housings have probably jammed up. You will need to have the cable and housings replaced.

2. Take your mountain bike to a DECATHLON workshop to have the derailleur adjusted. REMEMBER: You can have all the settings on your bike checked for free in the first six months following the date of purchase.

You should know that when the brake pads come into contact with the black trim on your rims for the first time it will make quite a noise. Don't worry, though. As you use your bike and apply the brakes more and more, a fine film of rubber will form over the rims and the noise will gradually disappear.

 

When you take your new bike out for a ride for the first time, a lot of parts move around and fall into place.

You'll hear the spokes on your wheels creak because of the residual torsion in them.

Your bike (from size S upwards) is fitted with double-walled rims, which help make the wheels more solid. That means they should not buckle in any way at all. If they do, then call in at one of our DECATHLON workshops to have them repaired free of charge.

Message for parents:

Young riders like to do tricks on their bikes (wheeling, skids, jumping off kerbs, etc). If done too often, however, they can cause play in the rear hub and buckle the wheels. If your child performs these tricks on a regular basis, speak to them and let them know the problems they can cause.

There are several things you can do to ensure your rear gears shift properly:

1. Check the position of the housing ends:

1a. Housing ends that are out of position can obstruct the derailleur cable when it is being pulled and prevent the gears from shifting smoothly. If a housing end is out of position, push it back into place.

1b. If the derailleur doesn't move even when the gear shifter is operated, then the cable and the housings have probably jammed up. You will need to have the cable and housings replaced.

 

2. Check that the derailleur dropout is not twisted: A twisted dropout causes the derailleur to become misaligned, preventing it from doing its job correctly. Look at your bike from behind and check to see if the derailleur is straight, as shown in the image below.

If the dropout is twisted or broken, take your bike to a DECATHLON workshop to have it replaced.

 

3. Take your mountain bike to a DECATHLON workshop to have the derailleur adjusted. REMEMBER: You can have all the settings on your bike checked for free in the first six months following the date of purchase.