How-to: Convert your trail bike to a ski-area friendly dh sled
Words and Pictures by Jason Van Horn
top: Inga B takes our DH converted Enduro down one of the trails at Northstar at Tahoe.
It's a familiar situation. You love ripping it up on trails, and enjoy hammering on your trail bike for hours on end. However, after watching some bike videos, a seed is planted, and the desire to step up your technical game and ride some downhill. Maybe you want to catch some air, so you have reading up on the freeriding revolution and you're ready to take the next step. Welcome to our first installment of a series of how-to's. Our goal is to get you headed in this direction, and to minimize your learning curve.
The first and most important step in beginning your freeriding education starts here, with the proper set up of your ride. In an ideal situation, you could go out and purchase a brand new 7 inch travel freeride bike, or a Specialized SX trail like your new hero Darren the Claw Berrecloth, or Cam McCaul. If you can't, then follow our guide to converting your bike into a bike that is ready to handle the learning curve of downhill or freestyle mountain biking.
Let's assume your bike is equipped with a minimum of 5 inches of travel and falls under the all mountain or trail bike category. If it doesn't, or is a bike you regularly boast about regarding its extremely light weight, turn back now. Cross country specific bikes simply aren't built for constant abuse, and while these spec changes on your bike will make it much more suitable for ski area/ black diamond trail riding, this style of riding will dramatically reduce the useful life of a XC specific bike. Our goal is to get you up to speed with a minimal amount of downtime, IE, hospital visits.
For this example, we're going to assume you have a bike comparable to our test sled, a Specialized Enduro Sl. These bikes come stock with 6" of travel front and rear and is quickly becoming the standard in long travel trail bikes. This is the bike we'll be setting up today:
a Specialized Enduro SL set up for some serious trail riding
Most all mountain bikes are already set up somewhat downhill friendly. This model has an 8" rotor in the front for additional stopping power, and a 7" rotor in the rear. The stem is a compromise between downhill and xc with its 80mm length. This bike is equipped with one of the best trail bike upgrades available, a gravity dropper adjustable height seat post. The tires are light weight for its class: Kenda Nevegal 2.35, front and rear.
This bike is already part way there, and would be suitable for most conditions- a great compromise between lightweight and downhill performance. We're going to take it a step further though, and set it up for black diamond ski-area riding; the type of riding you'll find at resorts like Whistler, Northstar, or Mammoth Mountain. Gravity assisted all the way, where the adding weight to a bike like this will actually help build your confidence.
Cockpit/ riding position
The first thing we're doing with this bike is putting a 50mm stem on it. If you're riding jumps and pure technical riding, the focus is on handling. Shorting the stem to a DH length puts your weight back, and while the top tube of the bike is still longer than a true DH or slope style ride, it will more closely emulate the riding position. We've also removed the Specialized suspension and gone with a Fox Talus 36, which is much more dirt jump/ x up friendly. We've also removed the all mountain enduro bar, and installed an uncut Specialized Demo DH handlebar. The added width of the downhill handlebars will make the bike considerably easier to handle in the loose rocky sections on the mountain, and increases the amount of leverage needed to control the bike.
The next step is to pull off the clip in pedals and add flat pedals. A lot of trail riders learned to ride with clip in pedals, but in order to learn proper riding technique and minimize the risk of crashing and injury, flat pedals are necessary. Yes you will see pro bmx racers and downhill racers racing clipped in, but I guaranty that when they are off the track, the majority of them ride with flats. You will not see any high level riders riding skinnies, or dirt jumping clipped in regularly. If you don't take the time to learn the basic skills correctly, you are only hurting yourself and hampering your own personal progression.
halfway there; dh bars, short stem, and flats. Time to add some burly wheels.
Tire/ Wheel selection
After the pedals, we pulled the wheels and added true downhill wheels and tires. The wider rims and dual ply tires add weight to the bike, causing it to deflect less on rock gardens adding a lot more control and stability. We went with a 2.7 in the front, simply because it was the biggest the fork could handle. The big tires with their additional air volume almost feel like you added an inch of travel to the bike. The main thing though is the feeling of control and the hook up you'll have in the loose rocky stuff. The loose gnarly dirt in the corners at Northstar is unlike the soil you'll ride on any of your locals trails. In addition, you'll be carrying a lot more speed and momentum, which will be necessary to clear the jumps and features found on the downhill trails like Gypsy or Boondocks.
Our last step was to remove the Gravity Dropper seat post and lightweight saddle. In its place we installing a SDG iBeam post and dirt jump saddle. You're riding downhill, and the time spent in the saddle, if you are riding with proper technique, will be minimal. The lower your seat while boosting the jump trail known as Livewire, the better. If you are still pinching your seat for stability at speed, its time to learn a better way. A chain guide is also a recommended addition. Since this bike is getting used in the Ashland Super D the following week, we got lazy and left it with a triple, the set up we'll be using in Ashland.
an Enduro SL- set up for slope style/ DH action
-and there you have it. This bike is now set up for riding at Northstar, or your next shuttle run with your DH bike riding buddies. Keep it real!
Stay tuned for the next round of how-to's. Next time around we'll cover your new riding position.