FEATURED ARTICLE
Randry Draper and Custom electric bike in Cycle to the Sun 2003 race in Maui
Randy Draper on his electric-assist mountain bike challenging the 10,000 foot slopes of Haleakala volcano on Maui. Photo's courtesy of Mitchell Silver

EV Cycling-to-the-Sun

In the toughest 36 mile hill climb in the cycling world, this custom electric bike proved it had the 'muscle' to make it to the top.

By Eric Peltzer

The road is billed as the world's steepest. It climbs nonstop from sea level to the peak of the 10,005 feet high volcano Haleakala on Maui, over a distance of 37 miles. The race up it, called Cycle to the Sun, was conceived of as the world's toughest bicycle hillclimb. But in this year's race, held on August 17th, a rider on an electric power assisted bicycle, using advanced batteries and a motor he made himself, has completed this endurance feat for the first time, near the head of the pack.

Randy Draper, the constructor and pilot of the modified bike, was drawn to the race not as a competition against human power, but rather as an extreme test of his unique design approach to light EV's. Using an unusually efficient 750 watt brushless motor he designed himself, a modified three-speed hub shifter from bicycle


Crossing the finish line

Inventor triumphant!

Photos courtesy of Mitchell Silver

component maker SRAM, and a 48-volt nickel-zinc Evercel battery pack, his full-suspension mountain bike is a test bed where total over-the-road efficiency is the guiding rule.

While most familiar commercial electric bikes use a 250 to 400 watt motor and lead acid batteries, Draper wanted more power for hill climbs, better efficiency at a wider range of speeds, and much greater range. His 7 lb. motor design has been used in prototype boats, bikes, and also is just as efficient as a generator.

Draper uses one in a windmill to add power to his solar array at his home in Lahaina, also on Maui. At one point he even made a 10 mile island crossing in a small solar powered catamaran powered by the motor.

The race would have been impossible to complete on any commercial stock e-bike. Not only is the road too steep, averaging 5% in grade but with long stretches over 15%, it is also far too long. Most e-bikes would have trouble completing a fourth of it before the batteries died. Even with better batteries the motors are not designed for long efficient runs at 750 watts and would overheat. But Draper figured with his efficient setup and a new type of EV battery with nearly twice the power of lead acids, the distance might just be within reach.

With assistance from Bob Ketell at Electricab Energy in California, the U.S. distributor of Evercels, Randy got four of these batteries and grafted them onto his specially prepared motorized mountain bike.

The race promoters were intrigued and enthusiastic about the prospect of an electric bike competing alongside the cyclists, though he was asked to start after all the human-powered entrants.

"I started at the back of over 250 pro riders from around the world. Starting from the beach I managed to get out in front by the 2500 ft marker. From then on I maintained the lead by close to 4 miles ahead of everyone until 1/4 mile from the 10,005 ft. summit. The Evercels stayed in the mid 50 volt range until the last 3 miles."

At the 6500 foot elevation point, the road enters the National Park, the crown jewel of which is the enormous volcanic crater towering over a commanding view of the sea and the islands. An alternative end point of the race is just inside the Park for those not wanting to test their lungs and legs at the higher altitudes.

"One park ranger yelled at me to stop at the park toll at the National Park entrance. As I sped by at 25 mph I yelled I was in the race."

His ride was somewhat more relaxing and cool than for the bicyclists pedaling for over three hours at their cardiovascular limits. Draper was wearing jeans and was shooting pictures while riding with his digital camera. "At all but the last juice or water stations I told them I was busy," he joked.

With the pedals on the bike all but inoperable due the extra-wide battery pack sitting in the middle of the frame, the entire course was completed on motor power alone - with one short exception.

"At half way, the voltage was still about 53 volts. I started loosing about 1 volt per mile with 10 miles to go. As the observatory was up on top of a giant hill, it was so close and so far away as I got within 1/4 mile. With only 36 volts at that point I started walking using just enough power to pull my 125 lb bike along."

With the finish tantalizingly close, but up a steep road, it looked like the end. But somehow the Evercel batteries, with their unique nickel zinc chemistry, had not quite given up the ghost yet.

"I was looking into the crater for 20 minutes or more a 1/4 mile away [from the finish], with the officials thinking I was crazy for not running up the hill. A spectator right there said I had the best time yet ever in the race at that point. With 1/8 mile to go, three cyclists passed me by to win, I did get a picture of them passing."

"Just for the hell of it I decided to jump on my bike and it took off to my surprise, and finished in 3 hours 3 minutes 58 seconds. My average speed was 12.2 mph, mostly in first gear, using 37.3 amp-hours from the batteries in 37.4 miles. I was working on my new bike all night to get it ready and never had time to test it or cycle the Evercel batteries. At the summit about a half hour after I finished I noticed the voltage at 53 volts so I rode it around at the top for another half hour. Hmm, amazing batts and I love 'em!"

As the only motorized vehicle on the course, some uninformed people may have thought he was a "cheater," but Randy saw this as a chance to promote his technology and the concept of electric bikes and EV's in general, to prove that they can overcome long-standing criticisms as vehicles with limited range and power.

Right after the race he was elated but nearly as exhausted as some of the other riders - from wrenching on his bike all night before.

"Right now I'm missing the awards ceremony but I haven't slept in 48 hours. It was a beautiful day and I caught the eye of everyone I passed in the race and along the road. It is documented by Cycletothesun.net. It is a worlds EV record for climbing steepest road in the in the world, as far as I know. "

What's next for the intrepid EV experimenter? Next year Draper hopes to have a demonstration EV division in the race with more bikes, possibly as a disabled person's division, and he is working to commercialize his technology and see it as a bike or kit available to the public. One thing can be agreed on, he has a unique and beautiful environment for testing his designs for electric vehicles and alternative power.

Links
The Race - www.cycletothesun.net
Randy Draper's site - www.ev-motors.com
Randy Draper's email solarcraft@webtv.net
Electricab - Evercel battery distributor www.electricabenergy.com
Evercel corporate - www.evercel.com

Times Article Viewed: 14019
Published: 23-Aug-2003

READER COMMENTS

blog comments powered by Disqus