Weighing more than 300 pounds and at risk for diabetes, John Tackett started biking — up and down his street. Four years and 140 pounds later, Tackett commutes daily on these two wheels, a 28-mile round trip from East Point to Buckhead.

And during this journey of self-discovery — which starts at 5 a.m. — Tackett has gained some valuable street-level perspective about the city.

John Tackett (ENLARGE)

John and Brenda Tackett are enjoying their new sizes and more energy. John lost 140 pounds, and Brenda went from a size 18 to a size 8.

John Tackett (ENLARGE)

John and Brenda Tackett before their weight loss.

• Interactive: View a map of Tackett's route ATLANTA'S TOUR DE CURE John Tackett will be one of the estimated 800 bikers expected to participate in Atlanta's Tour de Cure 2008 on Sunday. Here are details about the fund-raising cycling event to benefit the American Diabetes Association. When: On Sunday, check-in time is between 7 and 8:30 a.m., depending on the distance of your ride. Where: At Sandy Creek High School What: Fund-raiser is expected to raise about $350,000. The cycling: Bikers will pedal anywhere between 8 and 62 miles. If you have diabetes: Join the red team and ride as little or as much as you want. For more information or to register, go to diabetes.org. LIVING Latest Headlines: Zoo raises $40K in campaign to keep pandas  Georgia Aquarium to welcome 10 millionth visitor  Aquarium adds 4 sandbar sharks to exhibit  Cellphones serve as '$300 baby rattle'  Athens ranked among best places to live  • More Living Stories • Living photo galleries • Georgia Aquarium news and photos • Zoo Atlanta news and photos

On Sunday, he'll bike in Atlanta's Tour de Cure 2008, a benefit for the American Diabetes Association.

Here are some of the things you might notice about Atlanta if you put your car in park and tried a little pedal power.

• "At 5 a.m., you don't have all of the city background noise, and by being on my bike, I can see the city at a slower pace. I can stop and watch and listen. I hear geese honking above. I've seen a whole family of opossums cross the street. At Woodruff Park, my eyes once met a raccoon."

• "At 5 a.m., the city has not had a chance to get polluted for the day. It's cool and fresh, and you can smell the flowers. And there's a place near the Oakland City MARTA station that smells like cinnamon rolls."

• "I used to be cynical about homelessness. They used to be hidden from me. But now I see them. I see them sleeping in alleys or getting up and moving around to stay warm."

• "I remember after the tornado, I rode my bike down Peachtree, and the homeless people seemed to be walking around in a daze. These are people who may have had all of their goods in a bag and it might have gotten blown away."

• "I remember reading years ago about writing your own obituary and asking yourself do you feel comfortable with what it would say? Exercise used to be going from the couch to the fridge."

• "A couple guys at Five Points have gotten used to me, and when they see me stop at the light, they say, 'Go, Lance, Go! Go, Lance, Go!' Once they told me, 'Watch out, the street is wet,' and I didn't see it coming. So they really helped me out."

• "I was resigned to being an old, fat guy. But now, I am an adrenaline junkie. I have more energy. I went back to college to get my degree. I volunteer at the Georgia Aquarium. I run marathons and am about to do a half Iron Man. I want to take more risks. I want to parachute jump. I am more fully living life."