Cyclo-cross Bike Fit

BY: @mrbabcock

Cyclo-cross puts unique demands on its participants. A CX racer needs to be able to put down power over bumpy grass, slog through mud, blast through sand, and fly down tricky descents. They also need to be able to mount and dismount quickly and safely. These demands require a fit style that is unique to cyclo-cross.

The cyclo-cross fit is a compromise between bike handling, power output, and comfort (in that order). Bike handling comes first because all the watts in the world won’t do you any good if you spend your race braking through turns and bouncing off every bump on the course. Remember when Lance raced CrossVegas? He was arguably the fittest guy there, but he struggled because his handling skills were not up to par, and his ‘cross bike was set up like a road bike. Comfort comes last because a cyclo-cross race is, at most, 60 minutes long.

Many of you, dear readers, have spent the last six months exclusively on your road or mountain bike, so now is a good time to get back on the ‘cross bike and dial it in. To help you with this, I have enlisted John Verheul of JBV Coaching, Adam Myerson of Cycle-Smart coaching, and Eddie O’Dea of 55 Nine Performance.

GOING FROM ROAD TO ‘CROSS

If your road racing and ‘cross racing bikes are set up with identical positions, one of them is not optimal.” – John Verheul, JBV Coaching (www.jbvcoaching.com)

I asked John to tell me more about his view of road vs. CX fit, and here is what he had to say:

“For a road fit, you want to be stretched out for an aerodynamic position that also enables maximal steady state power. You don’t have to worry a lot about absorbing bumps or dramatically moving your body over the bike for technical stuff. Front/rear weight distribution is relatively even, so the bike handles predictably in corners, and it’s balanced so you can do rides of over 4 or 5 hours without too much weight on either the seat or hands.

“In CX, you need the seat a bit lower (~5mm, plus pedal stack height difference) to allow the bike to ‘float’ underneath you on bumpy stuff, and you need the bars a bit closer in so that you don’t get ‘over stretched’ on every bump. That also allows you to move your weight over the bike more to get the weight where you need it. Weight distribution is a bit further over the front wheel, to get the bike to go where you steer it, and to enable repeated accelerations (after every obstacle). You don’t need to worry as much about being aero, due to lower speeds, and the faster drafting sections being shorter in CX. You also don’t need to worry about 4-5 hour rides, you can use your road bike for the odd long training ride. Races are never more than one hour, and training rides on your CX bike are rarely more than two hours.”

In addition to the above advice from John, I think it is important to make a special point about hood position. Most of the new ‘crossers I see  run their hoods way too low. I asked professional road and CX racer and coach Adam Myerson (Team Smart Stop p/b Mountain Khakis & Cycle-Smart Coaching) about hood position, and he had this to say:

“For ‘cross, I prefer a hood height and angle that allows the wrists to be straight, rather than angled slightly down as they would be in a traditional road position. In ‘cross, you don’t rest on your hoods as much as you grip them in your hands like baseball bats. This allows you to push and pull on the bars with equal force, and really drive your bike across changing terrain. This can be achieved by rotating the bars up, or by moving the hoods higher up on the bars. Usually a combination of both works best.”

GOING FROM MTB TO ‘CROSS

The transition from MTB fit to ‘cross presents different challenges than the transition from road to ‘cross. Here is what Eddie O’Dea of 55Nine Performance (http://55nine.com) had to say:

“Cyclocross fitting, like the sport itself, takes a little from road and from mountain biking. CX does not require quite the same high torque that MTB does, but certainly higher than on the road so I use a mid point between the road and MTB solutions provided by WN Precsion (http://www.wnprecision.com/). The reach out to the hoods should be similar to the mountain bike, which is ideal for low speed handling. Get rid of those concave shaped saddles and get a flat one that allows you to move about instead of locking your hips in one position. This will let you get the torque while seated and still slide up on the nose when you need the high turn over on the flats.”

SO WHAT DOES IT ALL MEAN?

No matter which discipline you are coming to ‘cross from, you will need to make some adjustments to your fit. Roadies, in general, need to drop their saddle a few mm and shorten their reach a little. Mountain bikers need to adjust their position to let their arms and legs do the job that the suspension on their MTB does.

While the above are good rules of thumb, there is no “one size fits all” cyclo-cross bike fit. A proper fit must take into account height, weight, leg length, flexibility, and many other variables, so I suggest contacting a pro bike fitter like Eddie (www.55nine.com), John (www.jbvcoaching.com), or Adam (www.cycle-smart.com).

Comments are closed.