Yahoo!" I shouted into the wind. Sometimes on my mountain bike, I have so much fun that I have to shout. This was one of those times. I was on a smooth path going straight downhill. The wind was in my face, and I felt like an eagle in a full dive.

"Yahoo!" I didn't have to worry about my friend Tommy hearing me. We were both practicing for the yearly Summit Race, the biggest sport event of the area. I had left Tommy way behind on the uphill climb. Going down I had such a big head start, it would take him a week to catch up. And that was only if I decided to stop. At the speed I was going now, he would be two weeks behind me by the time I reached the bottom.

The Summit Trail was a bike path through the desert hills outside of the town where I live. It has sections where it is packed smooth. Other spots have big boulders; others are sand. I had been over the trail so many times, I knew all of it.

Because of that, I was ready for the big hole up ahead. I turned my handlebars slightly and aimed to the right of the hole. That sent me over a patch of bumps. I half stood on my pedals and let my knees take the bounces.

There was a sharp corner after that. I squeezed my hand brakes. I squeezed just a little. I didn't want to slow down too much. The timer on my wristwatch was counting every second, and I thought I had a good chance at beating my own record.

I leaned into the turn, loving life.

"Ya --" I didn't get a chance to finish. Some idiot with a pack on his back stood beside his mountain bike. Right in the middle of the path!

I hit my brakes as hard as I could. I pulled my weight back so I wouldn't fly over my handlebars.

The guy saw me coming and tried to pull his bike out of the way. But I could see I was going to hit him. I had to do something to avoid hitting him head-on and getting flipped off my bike.

I let go of my front brake and cranked hard to the left. At the same time, I leaned over, almost laying my bike flat. The back end skidded around. My back tire slapped into his front tire.

THUMP.

I dropped my bike and jumped clear.

"Hey," I said, "next time pull your bike to the side. You could get hurt parking smack in the middle of the trail."

"Shut up," he said.

I blinked in surprise. It was his fault I'd nearly hit him. If I hadn't made such a good move, both of us could have been hurt real bad. And he was telling me to shut up?

"Shut up?" I repeated.

"Shut up," he said again. He dropped his bike and picked mine up.

"Hey!" First he tells me to shut up and then he grabs my bike? "What are you doing?"

"What's it look like I'm doing?" he asked.

"Looks like you're taking my bike."

"Exactly," he said. "My bike has a flat."

"You can't take mine," I said.

He smiled a mean, ugly smile. He swung his leg to get on my bike. "Just try to stop me."

I stepped toward him. He was a couple of inches taller than me and a whole bunch of pounds heavier. I'm tall, but skinny, mainly from all the bike riding I do. Still, I wasn't going to let him take my Exotec-4 mountain bike. I had saved for a year to buy it.

I grabbed my bike by the handlebars and pulled. "Let go," I told him

Both of my hands were on my bike. That was a bad move. He punched at my face. Hard and fast. I couldn't bring my hands up fast enough to defend myself. His punch knocked me backward. I tripped over a rock and fell.

When I looked up, he was already on my bike and peddling away.

I jumped to my feet and dove forward. I managed to get my fingers around one of the straps of his backpack. His upper body spun toward me.

"It's my bike," I shouted. "Drop it!" I kept a bulldog grip on the strap.

He slipped one arm loose from the strap. Wearing just one strap, he twisted and punched me again.

"Hey!" I shouted. "Quit it!"

"Hey what?" someone shouted from behind us. It was Tommy. Tommy lifts weights. He's slow on his mountain bike because he blocks so much wind.

The guy on my bike saw Tommy. He must have decided that he would lose against us both. He tried to get away from me. I held on to his backpack, getting dragged along.

There was a ripping sound. The second strap of his pack tore lose. I went flying backward, and he went flying ahead.

I landed on my back with his backpack in my hands. He kept going down the hill, on my bike.

Tommy stopped beside me. "Your face, man. It's bleeding."

"My bike," I said. I managed to get up again. With one hand I held the backpack. With the other hand, I wiped my nose. It hurt. My teeth hurt. My face hurt. "He's got my bike."

"What are you talking about?" Tommy asked. "It's behind you on the ground. Why were you jumping that guy?"

"That's his bike on the ground. He's got mine. He stole it from me."

Tommy and I watched the guy on my bike. He was a long way down the hill already. There was no way we could catch him.

"Your bike?" Tommy said, like he couldn't believe it.

"My bike." I could hardly believe it myself, it had happened so fast.

We watched him turn off the Summit Trail and take another path, this one much narrower.

I looked at Tommy. Tommy looked at me. We had been everywhere in these hills on our bikes. We knew every single path. We both grinned. We knew the same thing about the path the guy just took.

"Well," Tommy said through his grin, "if he just stole your bike, it's a good thing he turned down a dead end."

He patted the seat of his bike.

"Hop on," he said. "Let's go get him."