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SALE
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KEYSTONE
build & price
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$2,039.00
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$8,840.00
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Shop By Model
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$2,039.00
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$2,719.00
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$2,039.00
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Let customers speak for us
from 110 reviewsI have the carbon version and wanted a second set. Very good quality for the money . Easily setup for tubeless.
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What a beautiful and well built frame! Great pricing deal and customer service was top notch.
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Love the bike. I have had brands of fat bikes and the flume performs the best. The aluminum frame had super clean welds and the paint has a high quality finish. The weight was several pounds lighter than bikes at the same price point Overall impressed with ride and quality
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My Crestone frame shipped very quickly via FedEx and arrived in perfect condition. It’s beautifully and looks incredibly sturdy. Bike is now built up and ready to ride. I want it to snow!
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I’ve never written a review before, but lets give this a shot.
My journey started with a my buddy buying an analog fatty and encouraging me into following him. I’m 63 years old, live at 8,400ft elevation in Eastern Sierra, been riding eMTN bike several times a week for just over a year, and it seams like everything I ride is uphill. I tried my buddy’s bike and I could not climb my normal route (1,000ft/7miles). I began researching fatty eMTN bike and quickly found Borealis Keystone. I lamented for several weeks and pulled the trigger early November 2024.
I had questions on choosing the right tires/wheels. The staff was very helpful discussing my riding style/needs and helping me select the right combination (26”, 4.8”).
The bike arrived 3 weeks later (delayed at my request d/t travel). It was meticulously packed and I assembled it on my workbench/clamp. It took about 4 hours (I’m kind of slow and it was the first time. I had not changed my own tire in 50 years). I called the shop for assistance in assembling/sequencing the rings at the head tube. They were quite helpful and got me back on track. I was surprised to learn the bike did not include pedals and it took me several days to acquire some. [Recommendation to Borealis, give options to choose pedals/opt out during the purchase process, just like tires and wheels].
This bike has exceeded every expectation. It handles soundly. Shifting and breaking were flawless without any user adjustments. I can travel uphill/downhill with confidence.
Regarding the battery/range. My ride last week (1hr:43min, 2,746ft elevation gain, and 14 miles) left me using 40% of the battery. I failed to charge that night. I followed this with a longer/steeper ride/climb (3 hrs, 3,865ft, 25 miles) and ran my battery dry in the last 1/2 mile. I mostly ride in ECO mode and occasionally use TRAIL and seldom use BOOST. I can conclude that if you need more than 5 hrs and 6,600 elevation gain, and 40 miles, on 3-5 psi, then you might consider carrying an additional battery.
Regarding versatility, during these two rides above, I traveled on snow, ice, sand, rock garden, slush, hard pack road base, gravel, asphalt, and 12” deep creek. During these two rides, I only lost control when crossing the creek and found an unexpectedly deep rut. This caused me to step off my bike. On other rides, I went down when hitting ice as I did not opt to put studs in the tires (live and learn).
There is truly no terrain this bike cannot handle (however, I recommend considering studs for ice, I have not tried this option).
Today, I noticed my rear brake was soft and the lever pulled back to the bar. I had to stop my ride. I’ll take it locally for a bleed tomorrow morning and hope to ride in the afternoon.
If you want to HAVE A BLAST on the mountain or just want to expand your riding season to 12 months a year, this bike is for you!
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I received my new Flume in two boxes and packaged well. Assembly and adjustment were easy and there is also a video to guide you through the process. After riding it for the first couple of miles in the snow I knew that I made the right choice by going with BOREALIS.
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The customer service closed the deal for me. They answered all my questions in detail and responded to emails within 24 hours. Bike packaging and assembly were pain free. Make sure you follow the assembly video. I am 100% satisfied which is rare since I’ve owned and rode many bikes over the years Thank you.
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Great carbon bike for this price point
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Needed an affordable, durable fatty upgrade and this set fit the bill perfectly. Bonus points for being the absolute easiest tubeless install ever!
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The bike is great . Fit to finish is impeccable. Comin from a mukluk this bike handles way better in deep snow. Better online manuals and vids for tech would be nice tho and are lacking.
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Ive been riding deep snow for years in montana and I can tell this bike works well geometry wise for deep snow riding. I like the build and weight of the bike.. 10 lbs less than my other fat bike. The bike was a easy assembly for me a non pro mechanic in my garage.
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Exactly what I needed and arrived earlier than expected.
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I looked at a ton of fat bikes, found a Crestone one size too small for me but on a big sale. Thankfully I looked on here and used the custom bike builder. I got exactly what I wanted, the newer Mastodon fork, and the weight shown on the builder was accurate! Totally blown away by this bike. As a Tig welder I really appreciate the effort they put into the frames they are beautiful. To top it all off, there is an integrated dropper port in the seat post! Couldn't get any better and the price is amazing. Would drop off the wine basket for the holidays if I didn't live on the other side of the country. They also answered all questions throughout the process. I am definitely not a bike builder expert haha.
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I have the carbon version and wanted a second set. Very good quality for the money . Easily setup for tubeless.
What a beautiful and well built frame! Great pricing deal and customer service was top notch.
Love the bike. I have had brands of fat bikes and the flume performs the best. The aluminum frame had super clean welds and the paint has a high quality finish. The weight was several pounds lighter than bikes at the same price point Overall impressed with ride and quality
Set them up Tubeless with Bud and Lou
Look good gonna try’em next week
Borealis set me up with valves and rim tape easy
My Crestone frame shipped very quickly via FedEx and arrived in perfect condition. It’s beautifully and looks incredibly sturdy. Bike is now built up and ready to ride. I want it to snow!