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Mountain Bike 27.5" Rockrider ST 100

Sale price: $149.00 Regular price:

Comfort first: cgf frame with raised position, 80 mm suspension, Ergofit hammock saddle with Flex stem, 27.5" wheels (26" in XS") so you stay comfortable as you ride

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Size: Select a size
Size Guide
Sale price: $149.00 Regular price:

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Final Sale: No returns or exchanges

See our return rules for heavy items

Free pickup

San Francisco, 735 Market St. Options

Select an available color and size to see options.

Model: 8628165

Product Videos

Product Features

A photo of the Mountain Bike 27.5" Rockrider ST 100 in use

Mountain Bike 27.5" Rockrider ST 100 | getting away on your first mountain bike tours. Have fun as you tackle small obstacles in the great outdoors

Comfort first: cgf frame with raised position, 80 mm suspension, Ergofit hammock saddle with Flex stem, 27.5" wheels (26" in XS") so you stay comfortable as you ride

Cycling comfort

Enjoy: the high position (CGF frame),80 mm suspension, hammock saddle, flex stem

Efficiency

Progress: light frame, 21 speeds, 27.5” double-walled wheels (26”1 wall in XS)

Precision

Control your path with tires with side lugs and V-brakes

Easy to use

Change speeds quickly thanks to the grip shifters

Lifetime warranty

Rockrider offers a lifetime warranty on the frame, handlebars and stem

Product Lifestyle Image Gallery

Image Gallery



Mountain Bike 27.5 

Mountain Bike 27.5 

Mountain Bike 27.5 

Mountain Bike 27.5 

Mountain Bike 27.5 

Mountain Bike 27.5 

Mountain Bike 27.5 

Mountain Bike 27.5 

Mountain Bike 27.5 

Mountain Bike 27.5 

Mountain Bike 27.5 

Mountain Bike 27.5 

Mountain Bike 27.5 

Mountain Bike 27.5 

Mountain Bike 27.5

Questions & Answers

Look for product information, frequently asked questions, opinions...

Question:

Is the seat adjustable on this bike

Answer:

Yes, the seat can be adjusted in height with a quick release. No tool needed

By Olivier on May 19, 2023 | STAFF

Question:

What is the weight capacity for Large and XL bikes ?

Answer:

The maximum capacity is 140kg or 300 lbs.

By Olivier on June 2, 2023 | STAFF

Question:

I could see that this cannot be returned.But if there is a shipping or manufacturer defect how do I handle it...

Answer:

Please contact our customer service team at customer.service@decathlon.com or from our contact form page. To help start your claim we will need the following information: Customer name, USS order number, Item name and documentation (images/video) of the defect you have noted in your item. Please look to provide as much detail as possible, so our team can properly review your case.

By Ashley on May 19, 2023 | STAFF

Question:

decathlon bike st 100 had a flat tire today. both the tire and the inner tube are more like broken. Where can I find the manual for the Bike to get the information the tire and inner tube for replacement. I saw the tire said: 27.5x2.00 Thanks

Answer:

Indeed you can replace the tire with 27.5 x 2 to 27.5 x 2.5 tires. for the tube I recommend this size. https://www.decathlon.com/collections/bike-tubes/products/btwin-schrader-inner-tube-275-x-19-25-x-48mm-15167?variant=1518952448013

By Olivier on June 22, 2023 | STAFF

Question:

What is the inside front fork dimension? We're looking a roof racks and we need to know if we need adapters for a 100mm mount

Answer:

The measurement inside the fork, where the hub will be placed, is 100mm.

By Nicolò on July 10, 2023 | STAFF

Question:

Is the bike true to size? For example is the small comfortable for a person at 5’4?

Answer:

Yes it is true to size. A small typically fits a person 5'1" - 5'5". Of course all people are build diffrently i.e long torso or legs - generally to sizing is accurate.

By Thierry on July 28, 2023 | STAFF

Question:

Does the bike have lights?

Answer:

This bike does not come with lights, they can be purchased seperately. The bike does come with reflectors.

By Thierry on July 28, 2023 | STAFF

Question:

What size should I order for my son? He is 6' and a half inch.

Answer:

XL will be the right size for him.

By Yann on Aug 8, 2023 | STAFF

Question:

Does the bike come assembled? Does it need any additional parts to be purchased separately (like pedals) to start riding?

Answer:

This bike come 95% assembled, you will need to put on the front wheel and adjust the seat height. It does come with everything you need to ride it, including pedals. But a kickstand and waterbottle cages would be extra.

By Thierry on Aug 15, 2023 | STAFF

Question:

It shows shipping is 200$, can i pick it up from store?

Answer:

We do not have store in the U.S. but we offer a free pick up from our warehouse if you are in the Oakland CA area

By Thierry on Aug 28, 2023 | STAFF

Question:

Whats the box total weight and dimensions?

Answer:

It depends the model and size of the bike but assume 8" Thick 32" tall and 52" wide, weight boxed is aproxamately 40lbs

By Thierry on Sep 18, 2023 | STAFF

Question:

Do you sell the individual wheels? I need a replacement for the back wheel since I don’t have equipment to true the wheel

Answer:

No we do not, I would recomend going to your local bike shop. As they typically stock a wide variety of wheels

By Thierry on Sep 26, 2023 | STAFF

Product Customer Reviews

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9134 Reviews
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Mountain Bike 27.5
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Fine

Yeah, fine

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Very good product 🤗

Very good product 🤗

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Horror movie

To begin with, I have never been disappointed with decathlon. I just think I came across the only faulty bike. I just wish I had been taken care of properly. I bought the bike at the beginning of September/end of August and 3 days later I already had a problem because the rear wheel had not been correctly mounted. As a result I already found myself without a bike because the wheel was warped and it had to be changed. When I bring the bike back for repair I am “accused” of hitting a curb or being run into it…? Although I claim to have had no shock, a Decath Rouen city center manager insists, explaining that it is impossible for the bike to have left the store like that. (As if decathlon was NASA). But anyway, I came across Léon from Rouen city center who took care of my bike, demonstrating that no spokes had been tightened and that it was impossible for all the spokes to loosen. A few weeks later Rebolotte the pads rub and plate 1 does not want to pass. So I travel once again to resolve the problem and this time I go directly to Barentin where I bought the bike. Once again my word is called into question that I would have touched the bike blablabla anyway anyway the adjustments are made (at least that's what I thought) a few days later the brakes rub again so I decide for the first time to take care of the problem myself without success obviously. Today I find myself with a bike with rear brakes that rub that I had to release to be able to move forward, a chainring 1 that does not fit and the fear of going to complain because I will still be made to appear like the customer in bad faith, all for €259… anyway, it was a long time no one will read this comment I'm going to wait a few months and buy a new bike… from Decathlon… we'll call it the Decath syndrome. This bike is great and decathlon too but at times we all make mistakes and we have to accept them… have a good day

For the most part satisfied

The bike arrived on time. Unfortunately, I had to take it to the bike mechanic first. The brakes were difficult to adjust and squeaked very loudly. On the Velomech it then turned out that the brake pads were installed incorrectly. Another 80.- more invested so that you could drive.😏 Now everything is fixed and ready to drive! Otherwise the bike is recommended, you just have to control everything well.

Very nice bike

Very nice bike

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good cycle bike

fully satisfied after using this bike

Good value for money

But I'm almost six feet tall and I took a size XL and I bend down a bit to reach the handlebars and it seems a little small to me.

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Good intermediate mountain bike for…

Good intermediate mountain bike for walks and daily trips

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Nice bike

Sturdy mountain bike with adjustable weight

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Bicycle

Excellent value for money

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My son loves his…

My son loves his mountain bike

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Good value for money.

Good value for money.

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Disappointment

The main disappointment before purchasing was the lack of choice. The model purchased was the only one at an affordable price and which included both front and rear gearboxes. I picked up the bike 2 days ago. I'm 1.72 m tall and the sales assistant recommended a L to me. I'm only now discovering that the XL also exists (maybe it would have been better). I discovered that despite having raised the saddle, the pedaling is uncomfortable and the leg remains too flexed. I also find that the distance between the saddle and handlebars is too short. The brake handles are positioned too low, forcing me to adopt a very comfortable hand position to be able to brake. The handlebars are too low, forcing me into an uncomfortable position and with my torso inclined more than 90°. The stand chosen by your seller is too short and can hardly support the weight of the bike. I'll stop here but only because I don't want to think about what else is wrong

Mountain biking

Good

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