How To Position Dirt Drop Handlebars On Any Bicycle

The purpose of dirt drop handlebars is to ride in the drops nearly all of the time. The drops of your dirt drops should be roughly positioned in the same spot as the grips of your flat bars on your mtb or in the same spot as your brake hoods on your traditional road bars. Sure, you can guess, trying different combinations of stem length, stem rise, and spacers, and seeing how it feels. Or not. Here is a method to position your dirt drops on any bicycle, even if you change wheels or fork. The only requirement is that you currently have a bicycle on which you feel comfortable when riding aggressively over rough terrain. This position is unique to you. Everyone is different.

Take that bicycle and set it in a corner with the rear wheel against one wall and the bars against the other wall. Stand the bike up as straight as possible and chock the front wheel. Make sure the wheels are equal distance (parallel to) from the wall the bars are leaning against.

Get down on your hands and knees. Measure the vertical distance from the floor to the center of the bottom bracket. Record this distance in millimeters and label it "stack offset." Measure the horizontal distance from the wall the rear wheel is touching to the center of the bottom bracket. Record this distance in millimeters and label it "reach offset."

Stand up. Measure the vertical distance from the floor to the middle of the spot where you place your hands while riding. On a flat bar mtb, it is the top middle of the grip. For a cyclocross bike with traditional road bars, it is the top middle of the brake hoods. Record this distance in millimeters. Subtract the "stack offset." Label this difference as "handlebar stack." Now measure the horizontal distance from the wall the rear wheel is touching to the middle of the spot where you place your hands while riding. Record this distance in millimeters. Subtract the "reach offset." Label this difference as "handlebar reach." Take your unique "handlebar stack" and "handlebar reach" numbers and guard them with your life. These two numbers stay the same for you, even if you change wheels, tires, or fork.

Now, make your best guess, and go ahead and throw on a bunch of headset spacers, high rise stem, and dirt drop bars. Repeat the above measurements to determine the dirt drop handlebar stack and reach. Remember, you are measuring to the middle of the drop section, because you want to ride in the drops all of the time. Are you close to your original numbers? Probably not. Now instead of guessing, you can calculate the number of spacers, stem length, and stem rise you need. Be aware that with some frames, you will not be able to exactly position dirt drops according to your original handlebar stack and reach numbers. If or when you get close to your original numbers, test ride in the drops only. Don't ride with your hands on the brake hoods. Position the brake levers so that you can easily reach them while riding in the drops. DO NOT position your brake levers based on how they feel when riding on the hoods. Again, DO NOT ride with your hands on the brake hoods. Do not wrap your bars yet either. Put a set of flat bar grips on the drops of your dirt drops. Slide them deep into the curve of the drop, and yes, the end of the bars will not be covered. Continue to make small adjustments and test ride in the drops until it feels perfect. If you still want to ride on the hoods, you really didn't want dirt drop handlebars in the first place.