Rockrider ST 50 MTB Black

REF: 8561304

MOUNTAIN BIKE ROCKRIDER ST 50 - BLACK

2020

This 26" mountain bike is designed for your first mountain bike tours in dry weather, lasting up to 1½ hours.

Everything you need to feel at ease: a frame giving you a more upright position to keep your back straight, 80 mm suspension, and an exclusive hammock-shaped Ergofit saddle. You'll love how comfortable the ST 50 is.

First use

Inflating your tyres

The recommended average tyre pressure is 2.0 bar.

If you're looking for more comfort and grip AND/OR if you weigh under 70 kg, you can reduce the pressure by 10% but without dropping below 1.8 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.

INFLATING-YOUR-TYRES-ROCKRIDER-ST540-MOUNTAIN-BIKE

Adjusting the height of your handlebars

Your handlebar comes set to the most raised position, which is the most comfortable position for riding.

For improved aerodynamics and more efficient pedalling, you can lower your handlebar so that your body leans forward and adopts a more racing-like position.

Follow the steps in this video to move the headset spacers that sit below the stem and lower the handlebars on your bike.

ADJUSTING-HEIGHT-HANDLEBARS-ROCKRIDER-ST540-MOUNTAIN-BIKE

Aligning your handlebar

Check out this video to learn how to align your handlebars.

ALIGNING-YOUR-HANDLEBAR-ROCKRIDER-ST540-MOUNTAIN-BIKE

Adjusting the stiffness of your fork

Your SUNTOUR fork has two preload barrel adjusters.

They are separate to each other.

Try adjusting the fork just with the first one. If the preload level is insufficient even when the first adjuster is screwed right down, you can always use the second to finish adjusting the fork.

Turn the adjusters clockwise to increase the stiffness of the fork and anti-clockwise to reduce it.

ADJUSTING THE STIFFNESS OF YOUR FORK
Bedding in your brakes

There's no need to bed in your V-brake pads to get them working efficiently. 

However, be aware that the first few contacts between the black paint on your rims and your brake pads may cause some noise. 

Don't worry! Over time, your brakes will cover the rims with a thin film of rubber and the noise will die away.

Adjusting the height of your saddle

Check out this video to learn how to adjust the height of your saddle.

ADJUSTING-SADDLE-HEIGHT

Positioning your brake levers

Check out this video to learn how to orient your brake levers.

POSITIONING-YOUR-BRAKE-LEVERS-ROCKRIDER-ST540-MOUNTAIN-BIKE

Changing your pedals

Check out this video to learn how to replace your pedals.

CHANGING-YOUR-PEDALS-ROCKRIDER-MOUNTAIN-BIKE

equipment-mountain-bike-st520-rockrider

The right equipment in case of a hiccup

You need to have the right equipment with you when you're out and about on your mountain bike so that you can take care of a puncture, a broken chain or any other type of setback. Here's a selection of products that can get you out of a tight spot or two.

Have a problem?

A wheel is bent

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

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

In the unlikely event a wheel is or becomes slightly bent or twisted, please bring your bike to any Decathlon workshop and they will make the adjustment free of charge, either:
1. As part of a free check-up in the first six months following the date of purchase.
2. As part of our €1 damage insurance plan (valid for two years).

Message for parents: Some technical tricks popular with young riders (wheelies, skids, jumping a kerb, etc.), if repeated too frequently, can also cause some play in the hub of the back wheel and cause the rims to twist.

If your child performs these tricks on a regular basis, speak to them and let them know about these problems.

wheelies and buckling of the ROCKRIDER ST 100 mountain bike's wheels
Repairing a flat

Unfortunately, a flat tyre is something that can happen to any of us.

The terrain (thorns, brambles, glass, nails, etc.),

or the way the bike is used (jumping over obstacles such as rocks, steps, kerbs, potholes, etc.), are the most common causes, respectively, of flat tyres due to a puncture (small hole) or pinching (small grooves close together). However, if you keep getting punctures, it might be because of:

- Poor assembly of the wheel in our factory, leaving a spoke poking into the inner tube

- A defective tyre or inner tube (porous)

- A poorly repaired first puncture with a foreign body (thorn, glass, metal shard, etc.) remaining inside the rim or tyre. It is therefore vital to properly diagnose the cause of the puncture and remove any foreign bodies before repairing the puncture. Not sure how to dismantle/remove a tyre, or how to repair or change an inner tube?

1. 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 sealant tube onto the valve of the flat tyre (valve should be in the lower position) and squeeze and hold to inject the foam into the inner tube. The tyre should become full and firm once more, allowing you to get back home safely.

2- If you've purchased our €1 breakdown insurance, you can have your tyre repaired at any Decathlon workshop.

3- To repair or replace the inner tube yourself, please refer to one of the video tutorials which you'll find below.

Rockrider ST 100 MTB Tyre Puncture
Your fork is too stiff

There are a couple of things you can do to "soften" your fork:

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

2. Do some basic maintenance: you can regularly care for your fork with a small oil can. Simply put a few drops of oil on the fork pivots and work the fork to help the oil penetrate into the blades.

3. Have the bike fully serviced in a workshop.

ADJUSTING-STIFFNESS-FORK-ROCKRIDER-ST540-MOUNTAIN BIKE

Your front gears are not shifting properly

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

1/ Check the cable and housing: 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.

2/ If the derailleur is not moving even after you have turned the grip shifter, it probably means that the cable and its housing have seized up. You will need to have the cable and housing replaced.

To replace them yourself, watch the video under "CHANGING A GEAR CABLE". Alternatively, bring your mountain bike to a Decathlon workshop.

REMEMBER: You can have all the settings on your bike checked for free in the first six months following the date of purchase.

NB: If you regularly ride your MTB in wet or muddy conditions, or if you regularly wash your bike with lots of water, then your cables and cable housing will need to be replaced more frequently. Washing your bike using a high pressure hose is highly discouraged as it can push dirt and dust into the cable housing.

ROCKRIDER ST 100 MOUNTAIN BIKE cable ends
Rear gears don't shift properly

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 is not moving even after you have engaged and disengaged the grip shifter, it probably means that the cable and its housings have seized up. You will need to have the cable and housings replaced.

You can choose to replace them yourself by watching the video under "CHANGING A GEAR CABLE" or bring your mountain bike to a Decathlon workshop.


2. Check that the derailleur hanger isn't bent. A bent hanger causes the derailleur to be out of alignment and therefore unable to function correctly. Stand behind your bike and check the alignment of the derailleur.

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


REMEMBER: You can have all the settings on your bike checked for free in the first six months following the date of purchase.

NB: If you regularly ride your MTB in wet or muddy conditions, or if you regularly wash your bike with lots of water, then your cables and cable housing will need to be replaced more frequently. Washing your bike using a high pressure hose is highly discouraged as it can push dirt and dust into the cable housing.

Cable ends position
The brake lever touches the handlebar too easily before braking starts

The lever is spongy and/or touches the handlebars before braking:

Loosen the thumbwheel and the locknut to adjust the cable tension so that the brake lever is firm but not too hard. Once you've got the setting right, tighten the locknut against the brake lever.

Please visit a Decathlon workshop to have this done by one of our technicians.

Your chain has broken

Has your chain broken? You have two options:

1- Repair it yourself using our video tutorial. You'll need a quick-link and a chain tool. 

2- Visit a Decathlon workshop to have it done by one of our technicians.

REPAIR-A-CHAIN

Your brakes make a noise

Be aware that the first few contacts between the black paint on your rims and your brake pads may cause some noise. 
Don't worry! Over time, your brakes will cover the rims with a thin film of rubber and the noise will die away.

Maintaining your mountain bike

Cleaning your mtb

To clean your bike properly, you'll need some bike cleaner, a sponge, and a brush.

Rinse off the bike with a hose and apply the bike cleaner.
Next, use the sponge and brush to work the cleaner in.
Give the bike cleaner some time to act before rinsing the bike off.

When hosing the bike off, make sure you do so from a few steps away so as not to damage the mechanical components.

Lastly, dry your bike using a cloth that is dry, clean and soft.

CLEANING YOUR MTB

Cleaning and lubricating your drivetrain

To clean and lubricate your drive train, you will need a degreaser spray, a soft bristled brush and a lubricant.

The first step involves covering the brake disc with a clean cloth to prevent any lubricant from getting on to it.

Next, spray the degreasing agent onto the entire drivetrain, scrub the cassette, the chain, and the rollers on the derailleur with the brush.

Let it sit for a few minutes before rinsing with a hose from a moderate distance.

Wait a little while to let the drive train dry before moving on to the greasing step.

For greater effectiveness, shake the can of bike lubricant and spray on the inner side of the chain.

CLEANING AND LUBRICATING YOUR DRIVETRAIN

Replacing a drivetrain cable

Is your drive train cable dirty, rusty, damaged, or do you find changing speeds to be difficult or unreliable? 

If so, you need to replace your drive train cable. To do so you'll need a pair of pliers, a screwdriver, a wirecutter, an Allen key, and a new set of derailleur cables and cable housing.

First, remove the cable from its housing. Remove the hood from the gear shifter, move the indicator to the last gear and cut the cable. This will allow you to remove all of the cable and then the housing.

Cut the housing to size and fit the end caps on the end of the cable, which is now ready to fit.

Install the cable on the shifter and pull it through the housing. Once done, put the cover back on the shifter and attach the cable to the derailleur. To adjust the drive train, tighten the cable if you have a hard time shifting to higher gears, and loosen it if you have a hard time shifting to lower gears.

Once adjusted, cut the cable and put a cap on the extremity using a pair of pliers.

REPLACING A DRIVETRAIN CABLE

Removing your rear wheel

Check out this video to learn how to remove your rear wheel.

REMOVING YOUR REAR WHEEL

Repairing a flat tyre

To repair a flat tyre, you will need: a bicycle pump, a basin with water, a dry cloth, and an inner tube repair kit.

Partially inflate the inner tube. Submerge the inner tube into the water to locate the puncture by the source of the bubbles.

Once you have located the puncture hole, dry off the inner tube with the cloth and rub the spot to be repaired using the sandpaper included in the inner tube repair kit.

This prepares the inner tube for glueing and ensures that the patch sticks to the inner tube as securely as possible.

Generously apply glue to the inner tube around the hole and wait 3 to 5 minutes.

Then apply the patch to the hole and hold it in place for a few minutes.

You can then fit your inner tube back into the tyre.

REPAIRING A FLAT TYRE

Replacing the chain

To do this, you will need: a chain tool, a new chain, and a quick-link.

Put the chain on the cog and on the smallest chainring. 

Remove the quick-release link using the quick-release chain tool and then remove the chain from the drive train.

Put the new chain on the last of the cogs and on the smallest chainring. This makes it easier to determine its optimal length.

Pull the chain down, pass it under the upper pulley of the derailleur.

Once you've defined the correct length, use the chain tool to cut the chain.

Lastly, install the quick-link onto the chain, turn the pedal so as to position the quick-link on the upper part of the chain, and use your hand to apply pressure and ensure it is firmly locked in place.

REPLACING THE CHAIN

Changing the brake pads

Check out this video to learn how to replace your brake pads.

CHANGING THE BRAKE PADS

Compatible accessories

COMPATIBLE ACCESSORIES
Mountain bike mudguard kit

Fit the KIT MOUNTAIN BIKE MUDGUARD KIT on your ROCKRIDER ST 50

mountain bike mudguard kit
500 Base stand

Fit the 500 CHAINSTAY STAND to your ROCKRIDER ST 50

500 BASE STAND
500 Black bike bottle cage

Fit the 500 BLACK MOUNTAIN BIKE BOTTLE CAGE to your ROCKRIDER ST 50

500 BLACK BIKE BOTTLE CAGE
100 Pannier rack

Fit the 100 PANNIER RACK to your ROCKRIDER ST 50

Rockrider ST 50 MTB Black
Pannier rack 500 onesecondclip

Fit the 500 ONESECONDCLIP PANNIER RACK to your ROCKRIDER ST 50

Pannier Rack 500 OneSecondClip
Child seat 100 frame

Fit the 100 FRAME CHILD SEAT to your ROCKRIDER ST 50

Child Seat 100 Frame

Spare parts

Selected spare parts

ROCKRIDER ST 50 HOTSPOT MOUNTAIN BIKE
1- Black steel v-brake-callipers

Discover the BLACK STEEL V-BRAKE CALLIPERS for your ROCKRIDER ST 50

BLACK STEEL V-BRAKE-CALLIPERS
2- Btwin 7- to 9-speed rear derailleur

Discover the BTWIN 7- TO 9-SPEED REAR DERAILLEUR for your ROCKRIDER ST 50

ROCKRIDER derailleur
3- Black 26" single-walled v-brake freewheel mountain bike rear wheel

Discover the BLACK 26" SINGLE-WALLED V-BRAKE FREEWHEEL MOUNTAIN BIKE REAR WHEEL

26" MOUNTAIN BIKE REAR WHEEL
4- 3- To 8-speed chain

Discover the 3- TO 8-SPEED CHAIN for your ROCKRIDER ST 50

5- TO 8-SPEED CHAIN
5- 2M brake cable housing

Discover the 2M BRAKE CABLE HOUSING for your ROCKRIDER ST 50

2M BLACK BRAKE CABLE HOUSING
SRAM-CASSETTE-10S

Go further

Need to replace a part on your bike? You'll find all our spare parts for the ST 50 MOUNTAIN BIKE right here.

User guides

MOUNTAIN BIKE ROCKRIDER ST 50 - Black
MOUNTAIN BIKE ROCKRIDER ST 50 - Black

NEED INSTRUCTIONS FOR YOUR ST 50? 

User guides

Need instructions for your fork? 

User guides

Need instructions for your drive train? 

MOUNTAIN BIKE ROCKRIDER ST 50 - Black

Haven't been able to fix your problem or find what you need?

Please contact one of our technicians who will be happy to help

MOUNTAIN BIKE ROCKRIDER ST 50 - Black

Our commitments

ROCKRIDER provides a lifetime warranty on your mountain bike's frame, handlebar and stem (under normal conditions of use).

All other parts have a 2-year warranty.

When you start riding your bike, some components will move slightly. This is why we offer a free tune-up of your mountain bike within six months of purchase.