“This is a full-on mini race bike.”
If you think full-grown adults have no business racing 175cc play bikes, a host of pro racers and amateur flat track stars are here to prove you wrong. Mad Dog racing has quickly one of the most popular, most competitive classes in all of flat track.
The bikes must start life as 156cc or less — a number based on the stock displacement of the Honda CRF150F — and the engine must be an air-cooled, two-valve four-stroke that can be modified up to 175cc. No age limits, no license required, and some of the most competitive bar-to-bar action you’re likely to see in any form of two-wheeled motorsport.
“Welcome to the wondrous, often insane world of Mad Dog flat-track racing. This is pure racing on small bikes where technique and skill reigns even more supreme than it does in other forms of motorcycle sport.” —Cycle News
A rider can pick up a 2003-05 CRF150F, thrown on a 175cc big-bore kit and a Bridgestone Trail Wing rear tire, and go racing. Of course, some racers end up putting an inordinate amount of cash into these small bikes, while others build their own.
Enter our friend Jake Drummond, one of the custom world’s brightest young builders, whose stunning Yamaha RD350 we featured back in 2018. Since then, Jake has built a Yamaha MT-07 with a custom aluminum perimeter frame — “The Omen” — which was featured on Bike EXIF, and he recently took a very exciting new “real job”:
“After nine years working for Sonex Aircraft building experimental aircraft and UAVs, I took a job with Polaris/Indian running the metal shop for the Industrial Design Department.”
Jake has also been hard at work on a Honda Hawk GT project for our friends at Cafe Racers of Instagram. But at some point, the Mad Dog itch came along, inspired by builder, racer, and friend of the blog August of Wisconsin’s Rosies Speed Shop:
“I was inspired by my buddy August Zeratsky. He built a 140cc flat tracker using a CL90 frame. It looked like such a fun bike to piece together and ride. I wanted to build something similar with some early ’70s flat track vibes.”
Jake started with a 1968 Yamaha YCS1 frame and swingarm, which he matched to a 4-speed Lifan 140 engine, Grom forks, a pair of 17” Sun Rims with RM85 hubs, and some very cool custom-shaped aluminum pieces:
“My favorite custom piece I made for this bike is the replica aluminum Champion gas tank. I have always loved the shape of that tank and I think it looks even cooler in aluminum.”
Jake recently ran his first Mad Dog race on “The Mini,” and he thinks it’ll be competitive with a bit more horsepower. That said, the bike is built more for fun and skill development than taking home trophies:
“It’s not a secret anymore that even the fastest racers practice on play bikes like the TTR-125. If you can ride a small bike to its maximum potential those skills carry over to riding the big bikes.”
Below, we get the full story on this mini ripper from Jake himself, as well as more photos from Zach Visser.
Mad Dog Flat Tracker: Builder Interview
• Crazy to think it’s been over three years since we featured your RD. Tell us a bit about what you’ve been up to since then.
That is crazy! The RD is still around but I’ve added a few to the collection since then. I built an aluminum framed Yamaha FZ07 that I call “The Omen.” That bike was definitely the biggest project I have ever taken on. Besides the motorcycle projects, I’ve been progressing with my “real job” also. After nine years working for Sonex Aircraft building experimental aircraft and UAVs, I took a job with Polaris/Indian running the metal shop for the Industrial Design Department. It was a big change that required me to move to Minneapolis, but I couldn’t be more excited about the opportunity.
• What’s the make, model, and year of the donor?
This bike is a mix of a lot of different parts mostly sourced from eBay. I started with a 1968 Yamaha YCS1 frame and swingarm. The engine is a 4-speed Lifan 140. The plan was to keep this build very simple but things escalated quickly when I found a killer deal on some 17” Sun Rims with RM85 hubs on eBay. The wheels were too cool to match up with cheap parts so I had to find something cool for the front end. Honda Grom forks worked perfectly.
• Why was this bike built?
I built this bike for myself. With pit bike prices skyrocketing I couldn’t bring myself to buy one, and also the mad dog class in flat track racing looked like too much fun to pass up. I wanted to build something that I could ride aggressively without worrying about laying it down or keeping it clean. This is a full-on mini race bike.
• What was the design concept and what influenced the build?
I was inspired by my buddy August Zeratsky. He built a 140cc flat tracker using a CL90 frame. It looked like such a fun bike to piece together and ride. I wanted to build something similar with some early ’70s flat track vibes.
• What custom work was done to the bike?
My favorite custom piece I made for this bike is the replica aluminum Champion gas tank. I have always loved the shape of that tank and I think it looks even cooler in aluminum. Other custom aluminum pieces include the rear fender and the fork guards.
In order to fit the Lifan 140 engine I had to build motor mounts and frame rails. The exhaust is pie cut out of 1.25” stainless tube and it uses a FMF two-stroke silencer which I shortened up to fit the bike better.
For the number plates, I vacuum-formed 1/8” thick ABS plastic over wooden form tools. I decided to make my own plates to fit the smaller scale of the bike. I had my friend Brennan print some custom backgrounds for me. (@kneeskees on Instagram).
To finish the bike off I made a custom seat with a fiberglass base and leather cover. The seat is kind of a hybrid between a solo seat with a P-pad and a more modern flat track seat.
• Does the bike have a nickname?
I usually call this bike “The Mini”. I’d like to eventually build my XS650 with a similar style so I guess the one will be call “The Medium”?
• You just had your first race on this ripper. What it’s like to ride?
I’m super happy with how this thing handles. It was built to fit into the Mad Dog flat track class, which always ends up being super close racing. With a little more horsepower I think this bike will be hard to beat. With that being said, the thing that most excites me about this bike is just play riding and having fun. It’s not a secret anymore that even the fastest racers practice on play bikes like the TTR-125. If you can ride a small bike to its maximum potential those skills carry over to riding the big bikes.
• What’s next for Jake Drummond – any more projects queued up?
The most exciting project I’m working on is a Honda Hawk GT for Cafe Racers of Instagram. I used to dream of having my bikes featured on their page, so building a bike with them is really cool. The Hawk GT is an awesome platform and I am really happy with the shape it’s taking. I’m using the existing lines of the frame to inspire the design for the all-aluminum subframe, gas tank, and tail section. The stance will be very similar to a Supermoto bike. Other than that I plan on spending my summer riding more. That is always the plan!