The sound, the smell and the sight of the smoke coming out of the exhaust – it was all part of the unique and beloved feeling of owning and riding a two-stroke. Unless you operate in the dirt bike world, those days have been over for more than a generation, and it’s been left to a faithful few to keep the ring-a-ding-ding alive and well out on the road. That nostalgia is even stronger when you lose a family member who was a smoky lover, and so, to pay tribute to his brother who had passed, one RD owner found just the right place to recreate the past glory. And being a friend of Roland Sands has meant this Yamaha RD400 has been given the full RSD overhaul; so get ready for a modern remix of the premix.
“We all love two strokes around the shop,” Roland says. “There’s something about the simplicity, the lightweight, the sound, and the smell that continues to captivate us. Growing up around two strokes, rebuilding the motors, and premixing gas is something that sticks with you. When you hear one, when you smell the premix burning at 32 to 1, it transports you back to a simpler time, a time before cellphones and the modern world swallowed up the kids. It takes you back to a day when having a ratio right, a five-gallon jug of gas, and enough oil to get you through the day was all that mattered. So here we are, going back in time with an RD400 build, and it feels damn good.”
The RD belongs to a friend of RSD and has been in their family for years, last owned by the customer’s brother who loved the thing, but sadly passed away before it could be rebuilt for more fun times. So what arrived at the workshop was “well-used and at the end of its current life cycle. Apart from a worn yet assembled motor, the rest of the bike was in bins. We set about a redesign at our customer’s request that kept the original form, chassis, and cases from the original machine, separating the usable parts from the swap meet items,” Roland explains.
The 398cc parallel-twin two-stroke engine was pulled straight out of the frame and sent off, requiring a full rebuild and restoration. It arrived into the safe hands of Ed Toomey, who has been working on old air-cooled smokers for years, primarily Yamaha and Suzuki vintage stuff. He rebuilt the motor from the ground up with a new crank, rods and top end, with extra compression for more fun, a stage two porting job, and head work. There is also a new reed cage, and the fuel is poured in thanks to a pair of Keihin 28mm carbs.
There is no need to premix your fuel, as the RD came with Yamaha’s ‘Autolube’ system, providing just the right mix with a twist of the throttle. The outside of the engine has all been beautifully powder-coated by Ed, and he even added some sweet gold-plated bolts as part of the assembly. To make hammering through the ratios a little easier, the gears have been back-cut and a new clutch has been added to avoid slipping. There is a sight glass added to the stock side cover, and then the beautiful ETD pipes, with the chambers an old Erv Kanemoto design, that really brings these motors to life and delivers a hell of a sound.
Staying with performance upgrades, a bike like this needs to handle like it’s on rails, and one of the best ways to deliver that is to lighten the rolling mass. It’s something Yamaha knew at the time too, making the 400C the first bike to get cast wheels from the factory. But decades later, RSD partners with Dymag, who make a hell of a product and sent over a set of 17in wheels, wrapped in Dunlop’s track-friendly Q5 tyres. To step things up even further, a Trac Dynamics swingarm has been added, a stunning raw billet item made from 6061-T-6 aluminium and featuring ultra-strong 7075 alloy axle adjusters.
The suspension doesn’t let the team down either, and Roland and Aaron picked out a set of Yamaha R6 forks, which have just the right length for the project. Obviously, they’ve been resprung to suit, and are fitted up with the R6 bottom clamp and a stunning RSD vintage upper. The rear shocks are fully adjustable and at 13.5” give plenty of scope to set the bike up for rider’s of all sizes. Braking was another big focus, and big radial Yamaha calipers, clamping twin discs with a Brembo master, provide serious stopping power on a lightweight machine like this. Best to have too much, however, and the rear gets a custom bracket for a single caliper setup and totally reworked rearsets to operate it all.
“We were originally going to go crazy with bodywork, but after further thought, we decided to keep the original tank and eliminate the upper fairing design and tank modifications, keeping the stock aesthetic intact with a TZ750 tail section. Instead of the fairing, we used an Indian FTR headlight and a massaged mount. This allowed us to focus on the performance aspects of the bike,” Roland tells us. And the minimalist look is spot on for this project, although the paint really takes things up a notch or two, with a beautiful custom colour and unique speedblock graphics. “It’s meaningful to bring a machine back to life that’s capable of making new memories as well as resurrecting the old. It’s as close to a time machine as we can get.” I love the smell of two-stroke in the morning.