The Suzuki GT380 was a two-stroke triple with ram air cooling and 38 horsepower on tap. The lighter weight sibling of the GT500 and GT750, this bantamweight smoker makes for one nifty cafe racer candidate.
Enter Pete Chase of Rhode Island’s Café Cycles, who’s known for his seat pans, fenders, and other custom metal motorcycle parts. Pete has been tinkering with motorcycles ever since the tender of age 9, when he bought his first bike — a 1979 Honda XR75. Since then, he’s worked on everything from cranes to exotic car engines to off-road race cars.
Last winter, he decided to build this 1975 GT380 on spec. The bike was in rough shape — seized engine and water in the case. Below, we get the full story on how Pete turned the unloved machine into the staggering two-stroke cafe racer you see here — one of our favorite builds from the 2018 Handbuilt Show!
Suzuki GT380 Cafe Racer: In the Builder’s Words
My name is Pete Chase, where do I begin when it come to motorcycles? I come from a really mechanical family — my dad has spent his whole life building custom sailboats, and my mom is really good with numbers and used to restore wooden furniture. My parents would send me off to my babysitter with broken alarm clocks, telephones, and other mechanical devices for me to take apart, to keep me busy and behaving for my babysitter.
I never had much money growing up but I bought my first motorcycle at a yard sale for $35, at the age of 9. It was a 1979 Honda XR75. This is where I learned to work on bikes I did every lick of work on that bike myself, and rode it for years until I upgraded to an XR200 in 8th or 9th grade. I went to a technical high school, where I had four internships and turned myself into a sponge, absorbing as much as I could from the mentors I worked with. The internships ranged from assembling new bikes at a motorcycle dealership, to restoring sports cars and fine engine building on exotic engines.
In college I studied mechanical engineering while working full time for a custom house builder, then a general car mechanic. After college I worked for a metal fabricator, building wrought iron railings, fences, and metal art. I then moved to a fast paced fab shop building cranes, marine equipment, and hydraulic systems. From there I up and moved to California where I got a dream job of building off-road race cars. I started out doing chassis work, but as my skills grew, I moved on to doing all of the aluminum work such as dashboards, consoles, and exterior body panels.
When I moved back to the east coast in 2008, I didn’t want to stop doing aluminum work, so I started Café Cycles, building seat pans, fenders and other custom metal motorcycle parts. The phone kept ringing, so here I am 10 years later, still doing what I love.
In the spring time, until fall, I mainly do general maintenance on vintage motorcycles (pre ’78). From Fall to Spring, I like to fill my schedule with at least three “big jobs” custom bikes and/or complete restorations, among other small jobs. If those three spaces aren’t filled, I generally build a bike “on spec.” I usually go out to my parts barn and pick a bike to start with.
Last winter I decided to rebuild this 1975 Suzuki GT380. It’s such a unique bike. Its a small displacement 3-cylinder 2-stroke with Ram Air induction. How cool is that? The motor was stuck, so I knew there was a lot of work to do. I started with the frame and did a modification that I am well known for, where I relocate the rear suspension reducing the spring rate and lifting the rear end up about an inch. along with lowering the front end about an inch, and changing out the front wheel from a 19 to an 18 (the rear wheel from a Honda CB350T). I am able to essentially reduce the rake of the bike allowing it to handle much better in the twisties.
I built a one-off aluminum seat cowl, which houses all of the electronics for the bike. I also built the front 1/4 fairing, headlight ears, gauge panel with gear position indicator, and chain guard.
Once the frame was completed, I started on the motor, which was worse that I thought. The case was full of water, and the crank had spun on its pin. The first guy I sent the crank to, to be rebuilt had to send it to another guy, Bill Bune Enterprise, who had the right equipment and parts in stock to get the job done. The crank came back, trued, with all new rods, bearings and seals, ready to drop in. I ordered a set of IMP ported pistons 1.5mm over bore. I sent the jugs out to the machine shop to be re-sized, and I filed the ports myself.
The transmission has all new bearings, I soda blasted the cases, bead blasted the jugs and head, polished all the covers and assembled the engine in-house. I am lucky to be friendly with Paul Miller Suzuki, who has and nut and bolt or bearing to o-ring, NOS, for all 60’s and 70’s Suzuki 2-strokes. He provided me with all my NOS parts.
Next I started on the paint scheme, while I figured out what I was going to do about an exhaust. I decided to go with a white tank, and a two tone blue, to keep thinks traditional Suzuki. I painted the tank in-house with DuPont Chomabase base paint. The paint job is straight out of the gun, with no sanding or buffing. The only exhaust system I found that might work with my modified frame and rear sets, was a 3-into-1 chamber pipe, but I couldn’t get myself to do it. From what I read, the pipe increased bottom end, same in the mid, but killed the top end. Some of the other aftermarket pipes available, like higgsspeed and Jemco, claimed to increase top end, but you lose down low.
There is a lot math, research, and development that goes into the design of a two stroke chamber, but in my experience a smaller displacement bike typically has nothing down low and everything up top, while a larger displacement 2-stroke has a more linear power band more like a 4-stroke. In general, you will get more power down low from a shorter, fatter pipe, and more top end from a longer skinnier pipe. In order to get what I was looking for I decided to take the general geometry from an existing aftermarket pipe, make it slightly fatter and shorter, in order to get an optimal mid range power. The results couldn’t have made me more happy. I also wanted this pipe to have a real one of a kind look, so I decided to make all three pipes exit out the right side of the bike. I then sent them out to the platers to be nickel plated.
Some of the specialty work was subbed up, but in addition to the in-house work I mentioned above, I spoked the wheels, did all wiring, metal work and tuning. It is important to me that my bikes are as much my artwork as possible and that I am not just a coordinator of other people’s work.
I would definitely classify this bike as a traditional Café Racer. You can view more of my work at Cafe Cycles or on Instagram @CafeCycles The photos taken of the bike, pictured with Firestone Tires, were taken by @mattFrancisPhotos, the studio Photo was taken by @RevivalCycles and the photo taken by the “Progressive wooden barrel” was taken by @JoshsteelePhoto.