Tyson Timperley, owner of Speedconcepts in Milwaukee, Wisconsin thought we might be interested in “Fatty,” a Yamaha R1 powered custom just a few months old that has a pretty unique look. It seems Tyson and Fatty’s owner Todd Treffert, were in a Milwaukee bar late one night, talking bikes. You know how that goes, another beer or two and one of them says, “Hey, I have an idea …” Ten months later, Fatty rolls out of the shop.
First, they picked up a used Yamaha R1, soon to be the donor for the engine and front suspension. Tyson made a frame jig and started experimenting with various designs eventually settling on the sweeping arcs of the hardtail frame you see here. He designed a hidden suspension under the seat to make up for it.
A Ron Davis racing radiator is covered by a fiberglass shroud which makes a strong visual statement along with the tank to give Fatty a style all its own.
The pipes are routed under and around the engine but it looks like they might be, … um, loud. Tyson used the R1 brakes and rotors up front along with the stock Yamaha wiring harness and gauge cluster, no need to change what works.
This is a street bike, it has a plate, but I wouldn’t plan any long trips. Definitely a different look, but after all, no rule says an R1 engine has to power a sport bike and Tyson, as you can see, has his own rules for what a custom should look like. I think it’s neat.