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Harley Drag Racing 101

Born and bred right here in the USA, drag racing has grown worldwide as one of the most popular forms of motorsports. Perhaps the best part about drag racing is that you can run just about any type of vehicle, including street legal Harley-Davidsons. Whether you ride a stock 883 Sportster or a monster 131-inch Road Glide, you’re free to participate as long as your bike passes the required safety inspection. With literally hundreds of drag strips across the nation, you’ll have no problem finding a legit location to run WFO with zero interference from the man. Aside from hosting sanctioned events, almost every strip offers “test and tune” sessions permitting wide open runs with no competition. This is the perfect time to get out there and learn the fundamentals of drag racing. Here are some basics for you to review before going out and making some passes down the track. 

 Before heading to the track, make sure you and your bike meet the track’s safety requirements. In most cases, this info can be found on the track’s website. Upon arrival, a tech inspector will look over your gear and your bike to make sure everything is in order. A full-face helmet, gloves, boots, leather jacket and a valid driver’s license are usually required. One piece of additional equipment that just about every track requires is an engine kill switch. There are companies out there that sell such products but you can easily do it yourself on the cheap. Just drill a small hole in the bottom of your engine start/stop rocker switch and attach a coiled lanyard with a small sheet metal screw. This device will flip the switch up and shut the motor down in the event that you and the bike part ways.

So you’re all geared up and ready to make your first pass. You’ll line up in one of the track’s staging lanes and await your turn to run. When your lane is called, you will proceed to the burnout box. The purpose of the burnout is to clean the surface of the rear tire and heat it up for better traction. Being that you’re running on street tires, a long smoky burnout really isn’t necessary because a street tire is not going to heat up like a race tire. Keep it short and sweet with a little bit of smoke. Pull your bike up past the water and then roll back into it to wet the tire. Pull forward out of the water, stand up, then use two fingers to grab the front brake lever, roll on the throttle and pop the clutch to break the tire loose and start spinning. Gear selection for your burnout will be a matter of experimentation. In many cases, first gear will work, but if you can’t get the tire to spin quickly enough, try second gear.

As you approach the line, observe the first few hundred feet of track ahead of you. You will see a lot of rubber laid down by previous racers. This rubber increases traction so you want to line up and use it to your advantage. Most of the time, there is one particular path off the starting line that provides the most traction. This is what racers refer to as “the groove” and this is where you want to be. It’s a good idea to start scoping out the groove while you’re back in the staging lane before you even get up to the burnout box.   

The Christmas tree is made up of a series of lights. The pair of lights at the top of the tree is the pre-stage and stage lights. Two beams of light shine across the lane to define the pre-stage and stage positions. When your front tire crosses the first beam, the pre-stage light will go on. As you roll the bike forward into the next beam, the stage light will come on, indicating that you are at the starting line. Underneath the staging lights are three yellow lights, a green light, and a red light. The yellow lights will come on quickly in sequence followed by the green .500 seconds after the last yellow. When your front tire rolls out of the stage beam, the timing sequence begins. The time between the light turning green and your front tire crossing the stage beam indicates your reaction time.  Therefore, .500 seconds is a perfect reaction time while .499 seconds will flip the dreaded red light indicating disqualification. The time from when your front tire crosses the stage beam and then crosses the finish line is your elapsed time. 

Once you’re staged, be ready for the starting sequence. Bring the rpm’s up to around 2500-3000 and preload the clutch. Once that last yellow is lit, roll on the throttle, release the clutch smoothly, and let it all hang out. It will take practice for you to figure out how to launch hard without spinning the tire or ripping a wheelie off the line. While both may be fun to do, they will kill your times. Once you cross the finish line, roll off the throttle, gently apply the brakes, and head for the turnoff where you will pick up your time slip. In addition to your reaction and elapsed times, there are a bunch of other juicy details that you will be interested in knowing later on, such as 60-foot time, 330-foot time, speed, etc.  Use these results as a basis for improvement in staging, launching and shifting.

There’s certainly a lot more involved in drag racing than this, but hopefully  I’ve piqued your interest and provided you with enough basic info to give it a shot. Aside from the obvious rush you will get from racing, the next best thing about it is the camaraderie among the competitors — especially at test and tune sessions. These folks will gladly answer your questions and make suggestions to help you improve your performance.  Just about everyone is willing to help out, whether it be wrenching, loaning tools or fronting parts to get you through the weekend. While there are a number of sanctioning bodies out there, only one is dedicated to American V-Twin performance. Go check out the All Harley Drag Racing Association’s website at www.ahdra.com for more information.

Written By: Bud Milza

Only published comments... Jul 23 2010, 08:10 AM by dtodd

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