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Mongoose Flatrock 21-Speed Hardtail Mountain Bike, 24 to 29-Inch Wheels, for Men Women Boys and Girls, Front Suspension, 14.5 to 18-Inch Aluminum Frame Options

  • Based on 313 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon

Arrives Friday, Nov 29
Order within 22 hours and 51 minutes
Available payment plans shown during checkout

Color: Silver


Size: 17-Inch Frame/26-Inch Wheels


Features

  • Hardtail MTB with a lightweight 6061 aluminum frame and 26-inch wheels is perfect for all terrain adventures, best fit to riders 5'4" to 6'2" tall
  • Element suspension fork improves performance and control while providing a smoother ride
  • 21-speed twist shifters and rear derailleur provide effortless gear changes when riding up an incline or speeding down a decline
  • Reliably stop with confidence using the front and rear alloy v-brakes, delivering dependable stopping power
  • Experience lightweight durability with the double wall alloy rims

Description

Explore rad new trails with the Flatrock mountain bike by Mongoose. The Flatrock comes equipped with a lightweight aluminum hardtail frame and Element suspension fork that are ready to tear down the trail. 21-speed twist shifters and rear derailleur provide effortless gear changes, while alloy v-brakes deliver reliable stopping power. Plus, double wall alloy rims offer lightweight durability. Get out there and explore with the Mongoose Flatrock.

Bike Type: Mountain Bike


Age Range (Description): Adult


Brand: Mongoose


Number of Speeds: 21


Color: Silver


Wheel Size: 26 Inches


Frame Material: Aluminum


Suspension Type: Front


Special Feature: Lightweight


Included Components: Flatrock Bike


Bike Type: ‎Mountain Bike


Age Range (Description): ‎Adult


Brand: ‎Mongoose


Number of Speeds: ‎21


Color: ‎Silver


Wheel Size: ‎26 Inches


Frame Material: ‎Aluminum


Suspension Type: ‎Front


Special Feature: ‎Lightweight


Included Components: ‎Flatrock Bike


Size: ‎17-Inch Frame/26-Inch Wheels


Brake Style: ‎Linear Pull


Specific Uses For Product: ‎Trail


Item Weight: ‎35 Pounds


Style: ‎Bike


Model Name: ‎Flatrock


Wheel Material: ‎Aluminum


Year: ‎2021


Seat Material Type: ‎Vinyl


Warranty Type: ‎Limited


Maximum Weight Recommendation: ‎250 Pounds


Assembly Required: ‎Yes


Skill Level: ‎Intermediate


UPC: ‎038675236301


Manufacturer: ‎Pacific Cycle, Inc


Item Package Dimensions L x W x H: ‎52 x 27 x 8.8 inches


Package Weight: ‎19.14 Kilograms


Brand Name: ‎Mongoose


Warranty Description: ‎Limited Lifetime


Material: ‎Aluminum


Suggested Users: ‎unisex-adult


Part Number: ‎R5836


Date First Available: December 10, 2020


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Friday, Nov 29

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Top Amazon Reviews


  • Easy to Assemble and Meets My Needs
Color: Purple Size: 16-Inch Frame/26-Inch Wheels
I live in a medium-sized neighborhood; I bought this bike to more easily travel within my neighborhood without having to use my car for very short trips. I have never assembled a bike before, but I was able to assemble this one quite easily. The instructions were a bit confusing, because instructions are included for several different versions of the bike, but once I acclimated to which instructions were applicable to me, it wasn't very hard. I did have to purchase a few items for assembly, but they were not very costly, and they will be useful additions to my toolbox. Assembly really only entailed attaching the handlebars, seat and pedals. All of the gear mechanism was already assembled. The bike is easy to ride and operate. So far, I'm completely satisfied with this purchase! ... show more
Reviewed in the United States on October 20, 2022 by Wendi McDaniel

  • The kiddo likes it.
Color: Teal Size: 14.5-Inch Frame/24-Inch Wheels
I had a little bit of trouble getting the breaks set correctly but that was definitely my own incompetence. I watched a YouTube video & was eventually able figure it out. Overall it's a great kid's bike and very pretty!
Reviewed in the United States on February 11, 2024 by Rin B. Rin B.

  • "You Get What You Pay For" Should be the Title for Every Bike Purchased in this Price Range
Color: Blue Size: 14.5-Inch Frame/24-Inch Wheels
It's a really heavy Mongoose but .. I knew that when I pressed the "add to cart" button. The hardware on the bike is mediocre but .. knew that. The bike does everything you need it to do .. unless you're a "bike person". If you ride this too hard .. it breaks. If you use it for transportation, or if you need a good beater for your kid who will be throwing this at the ground repeatedly until they move out of your house chasing some dream job in cosmetology or whatever nightmare they're dreaming of .. this is the bike for you. Assembly was complicated by the fact that it's just an okay bike. The tools they include are enough to assemble the bike with but, you can cut your assembly time in half if you just have some basic tools lying around the house. The bike rides and feels fine. With some fine tuning on the brakes and shifter mechanism, the bike would stop and shift fine. Solid "bang for the buck" on this but, if you spend another couple hundred bucks, there are better choices that would be worth much more than the extra investment. All in all .. this is okay and it's fine unless you're really trying to do anything outside the realm of "commuting". ... show more
Reviewed in the United States on July 27, 2023 by Sean C.

  • Nice bike
Color: Red Size: 18-Inch Frame/29-Inch Wheels
Easy to assemble, good suspension, we like this bike. It rides nicely, seems very well-made.
Reviewed in the United States on February 6, 2024 by Anais

  • Not well made, parts already braking, no customer support
Color: Red Size: 18-Inch Frame/29-Inch Wheels
My husband and I recently bought the above bike on Amazon for our son for his birthday. We studied reviews and felt good about this being a good bike for a big kid--he's almost 6' and a stout guy. He loved the look of the bike; however, after a couple weeks of use, we've been very disappointed in the quality and functions of the bike. Here are several items of note: 1) The handle bar--this bar, although sleek looking, does not offer much room for adjustment and it is very uncomfortable, even painful, to ride for our son, me (5'8") and my husband (6'1"). We all experienced pinched shoulders and neck even after riding it just around the block. A neighbor helped us put a different handlebar in to raise the grip a bit, and although it helps, it's not quite the right size for the bike, the overall grip is still pretty narrow. Which means we will have to keep shopping around to make adjustments. 2) The handle grips and gear shift--these are entirely too small and spaced too close together! My son's hand, if he grips with a standard 4 finger grip, overlaps with the gear shift, so gears are shifting when he's just holding on to the handlebars and not meaning to shift gears. 3) The pedal/crank set--there is a decent amount of wiggle room in this. As I understand, this should be a pretty sturdy feel, but it jiggles. It doesn't appear that this is anything we can adjust, it is as it came. We had the bike professionally put together, and the mechanic noted this right away. 4) The kickstand--it has already bent and bends forward with the weight of the bike and no longer works. Overall, we are extremely disappointed in this bike. We feel that for the money, we shouldn't be having all these issues right away with it. We reached out to the manufacturer, and have not heard any response back. I'd shop for a different bike! ... show more
Reviewed in the United States on August 2, 2023 by Joe Wilkins

  • No good quality
Color: Silver Size: 17-Inch Frame/26-Inch Wheels
All nuts damaged during installation, pure made in china
Reviewed in the United States on May 22, 2024 by Edmond M.

  • Very pleased!
Color: Purple Size: 16-Inch Frame/26-Inch Wheels
Arrived undamaged, box was in perfect condition. Instructions were a bit confusing at first, but once i studied them closely and figured out which type of bike parts i had, assembly was a breeze. Bike looks great in dark purple, very stylish. And best of all, it rides great!
Reviewed in the United States on June 3, 2023 by Rockheart

  • gret bike
Color: Teal Size: 14.5-Inch Frame/24-Inch Wheels
great bike
Reviewed in the United States on March 25, 2024 by Michael

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