“Looks like a brat, goes like a flat!”
For years, the Suzuki GN250 served as a capable 250cc runabout. The air-cooled, SOHC single cylinder engine offered some 22 horsepower and the bike was fairly lightweight at 281 pounds. While the bike has been largely overlooked by donor for customization, the crew of Trintaeum Motorcycles have a fondness for this “underdog”:
“Still it has everything you want from a base bike. It has a unique engine that sounds beautiful, is simple in its construction and, apart from the sub frame, it has some pretty nice lines.”
Indeed. What’s more, this was a special build for the Portugal-based crew, as it was commissioned by none other than their videographer, Simão, who didn’t want a show queen, but a flat track-inspired bike for daily use:
“His request was a flat track bike that could endure any occasion, one he could use everyday and everywhere, on and off road.”
The team completely rebuilt the engine, punching it out to 300cc, and reworked the subframe. As per Simão’s request, they built the smallest seat that could while still being comfortable, rewired the electrical system, and re-laced the hubs to 18-inch hoops with both a road and dirt configuration. Below, we get the full story on this “GN300” brat tracker.
Suzuki “GN300” Brat Tracker: In the Builder’s Words
The Suzuki GN250, what about this bike!? It is known that it got neglected in the custom scene — it’s kinda of an underdog. Still it has everything you want from a base bike. It has a unique engine that sounds beautiful, is simple in its construction and, apart from the sub frame, it has some pretty nice lines.
We could go on and on but to shorten the story out, we, at team thirty & one, love using the GN250. We’ve built several GN based bikes and decided to put all our knowledge and experience into this challenge. This request came from Simão! A very special request from an even more special dude! Simão is our videographer, an artist when it comes to capture the perfect shot and someone who loves flat track bikes! So, his request was a flat track bike that can endure any occasion, one he could use everyday and everywhere, on and off road.
With flat track bikes there is nothing more important than performance, but, here at thirty & one, looks are also at the top of our list, even more if we are talking about a bike that also has to shine on the road. So for this compilation, the boys had to aim for the best balance between both worlds.
We started by upgrading from the Suzuki stock cylinder to a 300cc configuration. The engine was completely dismantled for glass blasting and everything was buttoned with new rings, gaskets and a new chain of command.
When it came time to work on the fuel system, the team resorted to an already tried and tested method by installing a new Mikuni carb with a capsule filter, so getting an exhaust system to support intake was vital. As for the frame, we revised the rear end with a new look by installing the small turn signals inside the subframe tube. The seat was a challenge, mostly because we knew that it was going to be the main piece responsible for adding some comfort to the ride. Simão didn’t make it any easier, “I want it small, make it small, but comfortable!” he said.
The wheels were fully disassembled and the 18/18 conversion applied, with new spokes, bearings and seals. The tires choice for the road version were the Avon mk2 400/18 and for the dirt track version the Duro HF.
Now, suspension! In the rear end we went with the appearance of a brat, modifying its interior for better road and off-road stability. The front suspension was totally refurbished and lowered to get that brat look offering performance on flat track. The electrical system was completely redone and a new box was applied with a lithium battery, and a key ignition system installed (car type).
That’s it! Another job done and happy days for Simão! “Looks like a brat, goes like a flat!”
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