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Mongoose Grafton Adult Mountain Bike, Hardtail, 21-Speed Drivetrain, 17-Inch Aluminum Frame, 26-27.5-Inch Wheels

3.5 3.5 out of 5 stars 35 ratings

Price: $339.49 Free Return on some sizes and colors
Blue

Size Chart
US Adult Mountain Bike
Brand SizeRider Height (in)Wheel Size (in)
24 inch56 - 6624
26 inch64 - 7426
27.5 inch64 - 7427.5
Bike Type Mountain Bike
Age Range (Description) Adult
Brand Mongoose
Number of Speeds 21
Color Blue
Wheel Size 27.5 Inches
Frame Material Aluminum
Suspension Type Front
Special Feature Aluminum Frame, mountain bike
Included Components Bike

About this item

  • Aluminum mountain frame with modern geometry is great for ripping down rugged mountain trails with 27.5-inch wheels that fit riders 64 to 74 inches tall
  • Hardtail frame with suspension fork is ready for off-road riding and internal headset offers a clean, streamlined look
  • 21-speed trigger shifters provide smooth gear changes
  • Mechanical disc brakes deliver all-weather stopping power
  • 2.3-inch wide knobby mountain tires provide extra grip and stability paired with aluminum double wall rims that add lightweight strength

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From the manufacturer

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Product Description

Go all out off road with the Grafton Mountain Bike by Mongoose. Great for ripping down rugged mountain trails, this hardtail aluminum bike features a suspension fork, internal headset, and 21-speed trigger shifters for excellent performance every time you ride. Mechanical disc brakes deliver all-weather stopping power and speed control, while 2.3-inch wide knobby mountain tires provide extra grip and stability. Plus, those aluminum double wall rims add strength without weighing you down. What are you waiting for? Your wild ride has arrived with the Grafton by Mongoose.

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Customer reviews

3.5 out of 5 stars
3.5 out of 5
35 global ratings

Customers say

Customers have negative opinions about the quality and scratch resistance of the bicycle. They mention that the components break easily and the bike came damaged.

AI-generated from the text of customer reviews

4 customers mention0 positive4 negative

Customers are dissatisfied with the quality of the bicycle. They mention that the components break easily, and the brakes are horrible.

"...Very poor quality components which break easily so be careful with the assembly and fine tuning...." Read more

"...Got it put together and I took it for a spin. Brakes were horrible. I couldn't switch gears properly...." Read more

"...n’t refund my money, this is the worst costumer service and the product it’s garbage, don’t waste your money" Read more

"Horrible Quality..." Read more

4 customers mention0 positive4 negative

Customers are dissatisfied with the scratch resistance of the bicycle. They mention that the bike arrived damaged and scratched in many places. Some customers also report that the front tire is completely bent.

"The bike came completely bent, I called their customer support and they said they don’t have the..." Read more

"BOX & BIKE CAME DAMAGED. WHAT A DISAPPOINTMENT BECAUSE IT'S A BEAUTIFUL BIKE." Read more

"The bike is scratched in many places; besides that, the wheels were dirty, and the components were loose inside the box." Read more

"Front tire is completely bended..." Read more

Awesome bike
5 Stars
Awesome bike
Very easy to assemble no damage what so ever thankfully. Just needs some easy tuning on the gears and your all set. Overall i’m very satisfied with this bike.
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Top reviews from the United States

Reviewed in the United States on January 21, 2024
Color: TanSize: 26-Inch WheelsVerified Purchase
Very easy to assemble no damage what so ever thankfully. Just needs some easy tuning on the gears and your all set. Overall i’m very satisfied with this bike.
Customer image
5.0 out of 5 stars Awesome bike
Reviewed in the United States on January 21, 2024
Very easy to assemble no damage what so ever thankfully. Just needs some easy tuning on the gears and your all set. Overall i’m very satisfied with this bike.
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2 people found this helpful
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Reviewed in the United States on January 24, 2024
Color: BlueSize: 27.5-Inch WheelsVerified Purchase
The media could not be loaded.
 The bike came completely bent, I called their customer support and they said they don’t have the replacement part till April. I have no means of transporting the bike to return it and I live in a city where if I leave it outside for an Amazon return, it will get stolen. Don’t buy any of these bikes if you’re in the same situation. This was already repacked and sold as a return by Amazon. They didn’t check it throughly enough to see it’s defective.
Customer image
1.0 out of 5 stars Horrible Quality
Reviewed in the United States on January 24, 2024
The bike came completely bent, I called their customer support and they said they don’t have the replacement part till April. I have no means of transporting the bike to return it and I live in a city where if I leave it outside for an Amazon return, it will get stolen. Don’t buy any of these bikes if you’re in the same situation. This was already repacked and sold as a return by Amazon. They didn’t check it throughly enough to see it’s defective.
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2 people found this helpful
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Reviewed in the United States on February 17, 2024
Color: TanSize: 26-Inch WheelsVerified Purchase
Rides smooth and comfortable
2 people found this helpful
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Reviewed in the United States on October 5, 2023
Color: TanSize: 26-Inch WheelsVerified Purchase
Design is very nice. The frame and size seemed small for my height (5’6”).

Very poor quality components which break easily so be careful with the assembly and fine tuning.

Once one starts to assemble the bicycle, trouble starts. There were issues with every item that needed assembly. The instructions don’t help either.

Make sure one fine tunes all the gears and derailleurs before riding the bicycle.

Maybe Amazon should spend some money on assembly and fine tuning the bicycles it sells and after this sending them out to the customers fully assembled.
Reviewed in the United States on November 4, 2022
Color: BlueSize: 27.5-Inch WheelsVerified Purchase
Excellent bike at excellent price.
Reviewed in the United States on July 5, 2022
Color: BlueSize: 27.5-Inch WheelsVine Customer Review of Free Product( What's this? )
I was really excited to get this bike so my expectations may have been a little high. Although I'm not an expert, I've had many bikes of all kinds over the years from mountain bike to street bikes to hybrids and this one was a bit disappointing. It looks great and was pretty easy to assemble. It's strong and the gear shift is great. My main problem is with the front disc break.

I've never been a fan of disc breaks on bikes. They require some serious precision. I feel like I can fix about 70% of stuff on bikes but not disc breaks. The front fork didn't fit perfectly on the wheel so maybe there was an issue there from shipping but I got it on with some effort. But the break was rubbing the disk when I got it on. So I tried to calibrate and after about an hour tinkering (after adjusting the break, it was rubbing in one spot and so I pushed in that part of the disc and that seemed to fix that) and some added washers in there I was able to get it so that the disc didn't rub at all when rotating the wheel. I come back a couple days later to ride and it's rubbing again all the time. Really annoying. The pre-assembled back break is fine though I need to tighten it.

Along with that, the bike is just awkward. Granted, I'm used to riding two hybrids, so the lower handlebars are a change, but the seat is much more narrow and uncomfortable and the handlebars being wider than normal is weird.

The hydraulics are fine and the oversized wheels are great and provide a nice comfortable ride, though it's not the smoothest to turn (I can't figure out if that's from the handlebars or what).
Customer image
4.0 out of 5 stars Decent value but not ideal
Reviewed in the United States on July 5, 2022
I was really excited to get this bike so my expectations may have been a little high. Although I'm not an expert, I've had many bikes of all kinds over the years from mountain bike to street bikes to hybrids and this one was a bit disappointing. It looks great and was pretty easy to assemble. It's strong and the gear shift is great. My main problem is with the front disc break.

I've never been a fan of disc breaks on bikes. They require some serious precision. I feel like I can fix about 70% of stuff on bikes but not disc breaks. The front fork didn't fit perfectly on the wheel so maybe there was an issue there from shipping but I got it on with some effort. But the break was rubbing the disk when I got it on. So I tried to calibrate and after about an hour tinkering (after adjusting the break, it was rubbing in one spot and so I pushed in that part of the disc and that seemed to fix that) and some added washers in there I was able to get it so that the disc didn't rub at all when rotating the wheel. I come back a couple days later to ride and it's rubbing again all the time. Really annoying. The pre-assembled back break is fine though I need to tighten it.

Along with that, the bike is just awkward. Granted, I'm used to riding two hybrids, so the lower handlebars are a change, but the seat is much more narrow and uncomfortable and the handlebars being wider than normal is weird.

The hydraulics are fine and the oversized wheels are great and provide a nice comfortable ride, though it's not the smoothest to turn (I can't figure out if that's from the handlebars or what).
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2 people found this helpful
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Reviewed in the United States on June 18, 2022
Color: BlueSize: 27.5-Inch WheelsVine Customer Review of Free Product( What's this? )
Not a bad mountain bike, especially considering the price. Comes almost completely assembled, and almost anyone can finish putting it together. Just basic things like the seat and pedals. The frame is a nice light blue and even though it's a hardtail, the front suspension works pretty well for light off road and street use.

21 speed Shimano gears shift fairly smoothly and didn't need any adjustments, and the brakes work well. Cable activated disc brakes front and rear work perfectly fine for everyday use, no issues at all with those.

Obviously at this price some of the components are not the best quality and I was expecting that. But overall I'm very happy with how it rides and the feel of the seat and handlebars. Frame is aluminum so it's somewhat lightweight but it's not going to be the strongest thing and I wouldn't recommend it if you want to do any serious downhill riding. For just cruising around or going on dirt paths, it works well and I would not have guessed it was under 400 dollars just from looking at it. I'm not a bike expert but I've owned a few in my day and I'm really happy with this one. I don't expect it to last forever, but so far it's been a very solid mountain bike. Parts can be upgraded if you wanted to do that, it seems to use standard sizes for everything. I'm just at the height limit for this bike and I'm pretty comfortable riding it. It is a full sized bike so it may be a bit big for someone under 5 foot 2 or so.
4 people found this helpful
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Reviewed in the United States on March 8, 2024
Color: BlueSize: 27.5-Inch WheelsVerified Purchase
BOX & BIKE CAME DAMAGED. WHAT A DISAPPOINTMENT BECAUSE IT'S A BEAUTIFUL BIKE.

Top reviews from other countries

Kelsey Santiago
3.0 out of 5 stars Broken Parts Sent; Had to Immediatey Ask for Replacement Parts
Reviewed in Canada on July 30, 2023
Color: TanSize: 26-Inch WheelsVerified Purchase
I couldn't attach my handlebars because the joiner piece had a wonky bottom screw hole. Super annoying as it added weeks to me being able to actually use my bike.
Customer image
Kelsey Santiago
3.0 out of 5 stars Broken Parts Sent; Had to Immediatey Ask for Replacement Parts
Reviewed in Canada on July 30, 2023
I couldn't attach my handlebars because the joiner piece had a wonky bottom screw hole. Super annoying as it added weeks to me being able to actually use my bike.
Images in this review
Customer image
Customer image
One person found this helpful
Report
Peter Lewis
1.0 out of 5 stars Mild disapointment
Reviewed in Canada on August 30, 2023
Color: TanSize: 26-Inch WheelsVerified Purchase
Well bike is fine. Bottom bracket bearings loose. And rear tire bearings open as well. All in all you get what you pay for. Just have to spend a couple hundred getting it fixed. When it's new there should not be this issue.
One person found this helpful
Report