January 15th, 2015 12:08pm
Over the past few months I’ve been riding a Borealis Yampa thanks to the support from Team CoreCo and Borealis Fat Bikes. The Yampa was my first experience on a Fat Bike, except for the few times that I threw my leg over other fat bikes just to do a quick lap around the driveway or bike shop aisle, and it has been a wonderful surprise.
Just over two months after the break-in ride, the Yampa has already been riding over 1000 KMs and tested under the most challenging conditions Costa Rica has to offer. Gravel, sand, dirt, grass and the occasional paved sections have been part of the riding surfaces, not to mention the many types of mud that the tropical forest has to offer.
My current set up on the Yampa includes a 1x11 SRAM transmission which includes: a 28T front chain-ring paired with a 9-42 cassette, to tackle Costa Rica’s steep climbs and fast descends. The cockpit is made up with a variety of brands including a Truvativ carbon seat post, WTB Volt saddle, Easton flat carbon handle bar, Truvativ 100mm stem, Crank Brothers Eggbeater pedals and ESI Chunky Grips. The bike is completed with a pair of custom Nextie carbon 26 inch wheels and 45NRTH Husker Du tires.
Team CoreCo has made available for me the option to also run 29+ wheels with 3 inch tires. Although the Yampa is designed to work with both wheel set ups, most of my riding has been done on the 26 inch wheels, mainly because we were preparing to properly participate in the Fat Category at La Ruta de Los Conquistadores.
The overall impression from the Yampa is that is a bike made to have fun without a weight penalty. More than a few times I have stopped on the side of the trail to show a fellow rider how light the bike is. The most common comment heard from people on regular bikes is: “those are some big tires, it must be really heavy” or “that thing is huge, it must take an enormous effort to move it”. Seconds after lifting the bike, their faces change and they start to agree and inevitably would ask the rider next to them to also lift the bike to confirm that it’s not just one person’s perception of weight. Besides the weight, the Yampa has a very interesting geometry. The combination of the angles of the seat and head tube as well as the rake of the carbon rigid fork create a somewhat aggressive position, similar to a XC specific bike but with a great amount of control and comfort. I have toed the line on this bike for intense races lasting under two hours as well and steady 6+ hour efforts and the position has not been an issue. Rear and front thru axles, as well as clean looking and easy to use internal brake and shifter routing, round up my favorite attributes of the Yampa.
There are not many areas for improvement on this bike, however the main one we have noticed; specially for a cycling team based in rainy Costa Rica, where river crossings, huge water puddles and post ride bike wash are part of our daily routine, is that the frame allows a lot of water to get into it without an way to drain out. After a long ride in the rain our bikes come home with a few extra ounces of muddy water. We have tried taping over the non-used internal routing holes as well as adding generous amounts of grease to the areas where water could get in, however most of our efforts seem futile. Other victims of the tropical weather are the pannier/rack mounting bolts on the seat stays. They look great on the first ride, however after a few rides in the rain and with our regular humidity, corrosion starts to stain them and if removed, it creates more options for water to get into the frame
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Nextie Carbon Rims
Once our team mechanic had laced the custom red Nextie, 26 inch rims to Borealis proprietary hubs, we couldn’t wait to try them on the trails. The bright red and Team CoreCo decals make them impossible to go unnoticed and once they are spinning fast, they create a visual effect similar to circles of hot lava rolling down the trail. Besides great visual appeal, the Nextie rims are really light. The 65 mm width works really well with 4 inch tires because it creates a well rounded profile and their double walled carbon construction make it really simple to set up tubeless. We have paired the rims with 45 NRTH Husker Du tires and couldn’t ask for better results. The design on the Nextie rims provides an almost hidden groove for the tire bead to securely hook onto the rim. Not long ago I had a mental lapse after checking tire pressure and took off for a ride without closing the valve. I let the tire deflate almost completely, then rode it for about a kilometer back to the house and the bead never came off the rim. During the past La Ruta de los Conquistadores I rode the wheels for all three stages, which had very different types of terrains and all I had to adjust was the air pressure to better suit each riding condition. As low as 10-12 PSI for muddy, wet portions and up to 16 PSI for hard pack, gravel or paved.
My only wish to make these Nextie wheels complete would be to have color matching, long valves to go with them. The color matching to keep the great visual effect and the longer valve would make it really practical since the depth of the rims prevents some standard-length valves from sticking out long enough to get a secure lock with a pump or in the worse scenario, with a CO2 trigger.
All credits belong to Jeff Herrera, Team CoreCo and Borealis Fat Bikes.
http://www.borealisbikes.com/bike/yampa
Location: News >> Borealis Yampa Reviewed by La Ruta Class Winner
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