Xprezo GrosBig

My fatbike is Gros-er than yours! This week MTBVT had the opportunity to check out the new version of Xprezo Bike’s GrosBig fatbike.

This bike is strikingly evolved beyond the handfull of first generation GrosBigs that Xprezo turned out last season. And the GrosBig V2.O is arguably one of the more refined Xprezos to date. In place of the previous steel frame is a beautiful hydro-formed tube set with one of the lowest stand over heights in the industry. Add that to one of the lowest bottom bracket heights available and the overall slack geometry and you have a beauty of a bike that stands out from rest of the fatbike herd.

Before we got our hands on it Iride owner Paul Hammond built up the frame and took it our for an inaugural test run.

“I got to hang out with the Gros Big for a few minutes yesterday while it was in the shop for assembly. The first thing I noticed was the geometry, it’s not an XC bike, it’s a mountain bike! At this point I went to putting the bike together with some excitement, almost missing the finer details like the internally routed cables, CNC’d chainstay yoke, and 170 mm symmetrical rear spacing. A little lube on the chain and some Deity pedals and I was ready to go for a spin. Pedaling up the lot was rather quick, the aluminum frame did a nice job transmitting power to the rear wheel and the 3.8″ Nate tires took away any harshness that might be there. I can only imagine how it will be with the 4.8″ tires. When I turned the bike downhill, it became clear that I was riding a very different fat bike. The slacker geometry and suspension fork make the bike a joy to ride. Carve a corner? Sure. Pop off a rock? Sure. Rail a berm? Sure. The future of fat bikes is here, and it’s sweet.”

Here’s the beta direct from Xprezo on the bike:

We worked hard to find the best geometry and components. The geometry is designed to accept an 80mm RockShox Bluto and a Stealth dropper post. We strongly recommend you opt for a rigid carbon fork, normal seatpost, and mechanical disc brake. Simplicity and cold go hand in hand. As for the inevitable few hike-a-bikes, you will be grateful for the internal cable routing (all cables are full length to avoid rust and corrosion of the wires caused by the elements.

WHY THERE IS A MIX OF SPACING WITH
A 197MM REAR HUB AND A 170MM CRANKSET SPACING?
To obtain the best chain line, and to offer a comfortable and natural pedaling position. No more cowboy style that you experienced with a 190mm wide crankset, if that bums you out go find a bar with a mechanical bull you can ride!

WHY OFFER A ROCKSHOX BLUTO WITH ONLY 80MM OF TRAVEL?
Because with at least 4 inches of tires, we think that there is only need for a little damping here. Because the GrosBig is the only Fatbike on the market designed and suggested with the goal to work with both types of forks: drawn with a fork with an axle-to-crown of 468mm, (with a 25% sag, a 820mm Bluto is 471mm high, so the geometry is not modified and the handling is still really good).

THE GEOMETRY
We created the GrosBig with big Xprezo ideas for sure! A winter snow bike, but with an effective geometry that is fun to climb, and really cool to handle and push on the downhills and corners. As the geometric numbers have changed a little bit in the last years in the mountain bike scene, we opt to adapt them on a fatbike. We want you to feel like you’re riding a rally car, not a grocery cart.

SO, WHAT DO WE REALLY WANT IN A FATBIKE?
The lowest possible standover! Of course, snow isn’t the most stable and predictable thing. Did you ever try to get on a fatbike, with feet on each side of the trail? A low standover is more than welcome in those situations and the Grosbig is more than an inch lower than the average of the market. Your future kids will be grateful.

It also has the lowest bottom bracket on the market (8mm under the average), but just high enough for the tight turns with the roots or rocks not to hit the pedals, the trails are literally transformed into pumptracks and we can enjoy a low BB to pump it and to push it harder in the corners.

We also designed the bike with the shortest headtube length possible: with 4 inches on a medium, we have a manoeuvrable and precise machine when the pumptrack points down, but with just enough forgiveness using a 690 head angle. We obtain a stack of 23 inches on a medium, 1 inch below the average, and the reach is a little longer to put the weight on the front wheel.

And for climbing? No more unwanted wheely. The seat angle is steeper to be more comfortable on the saddle for the long climb and to be more efficient on each pedal stroke.

So, both Iride Paul and Xprezo seemed to be impressed, but we had to know for ourselves how this thing handled. We headed over to the local Xprezo rep Jason’s house. But ol’ mother nature had other plans. It had been pouring rain for a few hours and no one felt like getting wet. But how would we put the GrosBig through the rigors of MTBVT’s standardised  and most scientific “ridden and reviewed” testing program?

Simple, we grabbed a four pack of Heady Toppers and hammered the beast around the comfy dry confines of the barn! Two spent car tires and a piece of plywood later we were able to examine just how well the Bluto fork added to the sweetness of this bike’s impressive modern posture.

Even Lou was impressed.

Now, I’m happy to tell you that I did manage to sneak in a decent trail ride on the rig once the weather let up. And here are my thoughts in a nutshell. I want one. And I concure with Paul. The bike rides great. Particularly at speed down hill. And I wouldn’t hesitate to rotate the GrosBig into my regular riding schedule in the summer. It’s a ton of fun and hands down the best feeling fat bike I have ridden to date.

Spec’s for the build we rode:

Cost: Approx’ $3700
Approx Weight: sub 30-ish lbs (28 lbs on the rigid fork version)
Frame: Gros Big Aluminium 6061
Rear Axel: Maxle Ultimate 12×197
Head Tude: FSA Orbit CF-40 Tapered Fully integrated
Fork: Rockshox Bluto 80mm
Saddle: Chromag Moon DT
Seatpost: Truvativ Stylo T30 30.9mm Noire
Stem: Truvativ Stylo T30 75mm
Handlebar: Chromag Cutlass 730mm
Grips: ODI Cross-Trainer
Shifters: Sram X7 10v
Rear Derailleur: Sram X9 Type 2 10v Medium-cage
Crankset: Race Face Turbine Direct-Mount
Chain: Sram PC-1051 10v
Cassette: Sram PG-1050 10v 12-36
Brake Levers: Avid FR5
Brakes: Avid BB7 Stainless
Discs: Sram CenterLine 180mm
Rims: Rolling Daryls
Hubs: 9Zero7 150×15 and 197×12
Spokes: DT Swiss Revolution
Tires: Surly Nate Tire 26 x 3.8″ 120tpi Folding

And for the nerdiest of bike nerds… go ahead, get out your magnifying glass and calculators (or click to enlarge):

For folks looking to purchase or demo a GrosBig get in touch with Dune at Green Mountain Bikes down in Rochester, Gene at Belgen Cycles in Richmond, or Paul at Iride in Stowe.