What if Yamaha and Bimota teamed as much as construct a fortieth anniversary RZ350?
That’s the query San Francisco-based engineer and highway racer Julian Farnam requested himself. After all, that will entail combining the legendary liquid-cooled, YPVS-equipped two-stroke parallel-twin from the Yamaha RZ350 — one of many baddest street-going people who smoke of all time — with a bespoke chassis, revised geometry, and fashionable suspension, brakes, wheels, and extra.
It wouldn’t be the primary Yamaha-Bimota creation — Jon Ekerold gained the 1980 350cc World Championship on the Yamaha-powered Bimota YB3, in spite of everything. Nonetheless, since such a machine clearly wasn’t within the playing cards for the fortieth anniversary of the ’83 RZ350, Julian got down to create his personal “2023 Yamaha RZ350.”
Julian was uniquely ready for the mission. Whereas he designs electrical farm tractors by day, he says he’s only a huge child at coronary heart who likes to construct issues, and bike chassis design has all the time fascinated him. In truth, his first huge mission again in 1990 was his Yamaha A-N-D FFE 350, that includes an experimental forkless chassis with a Yamaha RZ350 engine!
Round 2000, Julian began his personal body firm — A-N-D Autos — and started to provide a Kawasaki EX500 chassis package known as the AK-1, which noticed a great deal of success on the observe:
“High quality was obvious, and there have been particular shades of Bimota within the brightly painted trellis spars mated to milled alloy rear plates. The AK-1 competed in AMA Professional Thunder and AFM Twins, with some notable victories in AFM – A-N-D framed bikes took 2nd and third in 2001 and gained the championship in 2002.” –Silodrome
There was a whole lot of discuss round an identical trellis-style body package for the RZ350, however when no one put their cash the place their mouth was, Julian determined to take issues into his personal fingers:
“About 4 years in the past I stated ‘fuck it’ and determined to construct one for myself simply because I needed one.”
The complete chassis — body, subframe, swingarm, and so on. — is all custom-built, with an asymmetrical body design that permits bigger diameter enlargement chambers to be run on the correct aspect of the bike.
Julian goes into the complete course of in his 30-page construct thread on BARF (Bay Space Riders Discussion board), with the whole lot from his preliminary design sketches to the complete execution of the bike you see right here — together with all the many detours, challenges, errors, classes, and triumphs alongside the best way.
The bike weighs in at simply 290 kilos with a half tank of fuel and makes an estimated 75 hp from the 375cc Tony Doukas Racing engine. Whereas Julian hasn’t ridden the bike as pictured but, he has logged over 600 miles on a prototype with the identical geometry:
“I typically discuss with the dealing with as ‘telepathic.’ It’s nearly as if the bike is aware of what to do with very minimal rider enter. It’s an absolute pleasure to trip!”
Julian’s “2023 RZ350” was a stand out from this 12 months’s One Moto Present, and we will’t wait to see what this Bay Space mad scientist seems of his workshop subsequent.
Yamaha RZ375: Builder Interview
• Please inform us a bit about your self, your historical past with bikes, and your workshop.
I grew up using each filth and road bikes within the 70s and 80s. By my mid-20s I used to be highway racing on RD400s and RZ350s. I nonetheless trip as a lot as I can. However to be trustworthy, I most likely spend extra time in my store than on a motorbike.
My academic background is in transportation design from Artwork Middle Faculty of Design. I at present work as a mechanical engineer for an organization that manufactures electrical farm tractors. However inside I’m only a huge child who likes to make stuff.
For some cause I’ve been notably thinking about bike chassis design. I’ve spent numerous hours learning how bikes do what they do. I’m notably thinking about various suspension configurations and am an enormous fan of individuals like Tony Foale, James Parker, Nico Bakker, Regular Hossack, and others who’ve developed alternate options to the trendy telescopic fork. My first huge moto mission was an experimental forkless chassis additionally powered by a Yamaha RZ350 engine.
In my very own moto work I are inclined to put on two hats. Usually, I take the position of a scientist, or extra precisely a mad scientist. I’m eager to strive new and unconventional issues simply to study and see what occurs if I strive one thing bizarre. Then with different tasks I’ll placed on my engineer’s hat and apply greatest practices to create one thing that may carry out on the highest degree.
I reside within the San Francisco space and have spent most of my profession commuting by way of public transportation. This has allowed me to spend a lot of my commute time filling sketch books with bike ideas. From sketches, I rapidly convert my concepts into CAD. From there it’s (often) a straightforward transition to constructing elements.
From early on, I’ve all the time needed a well-equipped residence store. After shopping for my first home, I began accumulating instruments and tools. My two favourite machines are my Hitachi 2M horizontal mill and a Victor 16 x 30 lathe. The Hitachi has very uncommon vertical head that got here as a manufacturing unit choice. It’s a big machine and the vertical head makes it very versatile.
The Victor lathe has a comparatively brief size relative to the swing diameter. It’s excellent for making bike elements. I’ve even used it when making my very own wheels. I’ve additionally received a primary Bridgeport mill, a 20” Apex sander, a 250 amp Miller “blue field”, and a bunch of different primary steel fab instruments.
• What’s the make, mannequin, and 12 months of the donor bike?
That’s a humorous query. The engine is from a Yamaha RZ350, however there by no means was a “donor bike” per se. That stated, there are elements on this bike from a Yamaha R6 (tank and seat), Suzuki GSXR and SV650 (forks and wheels). Main parts just like the body and swingarm are all scratch-built and distinctive to this bike.
• Why was this bike constructed? (Buyer mission, firm promotion, private, and so on.)
This was a “properly, fuck it” mission. After the success of my AK-1 race bikes again in 2001/2, I’ve had a number of individuals asking about {custom} RZ frames. None of these conversations resulted in bikes getting constructed. So about 4 years in the past I stated “fuck it” and determined to construct one for myself simply because I needed one.
That stated, I’m really constructing three and one has already been delivered to Tony Doukas for his staff to do some observe testing. The third bike might be constructed with a couple of minor adjustments. If I resolve to construct extra and provide them on the market is but to be decided. I’ve definitely received curiosity, however I must catch my breath at this level and consider how I wish to proceed.
• What was the design idea and what influenced the construct?
The idea was sort of a “what if”… what if Yamaha and Bimota teamed as much as construct a fortieth anniversary RZ350? After all that by no means occurred, so I made my very own interpretation.
• What {custom} work was executed to the bike?
The complete chassis (body, sub-frame, swingarm, and so on) are all custom-built. The tail can also be a {custom} piece and has an extended story as to the way it was developed. I might and have written many pages on how the bike was constructed. (Particulars might be present in my construct thread on BARF.)
• Does the bike have a nickname?
It’s an AY-2…however most individuals gained’t know the importance of that designation, so I simply name it a “2023 Yamaha RZ350.”
• Any thought of horsepower, weight, and/or efficiency numbers?
Tony Doukas who constructed the engine has an an identical engine that’s making round 75 hp. He’s assured that I ought to count on the identical. That’s not dangerous for a motorbike that suggestions the scales proper round 300 lbs.
• Are you able to inform us what it’s prefer to trip this bike?
The bike as pictured hasn’t been ridden but, nonetheless I’ve logged over 600 miles of California backroads on a prototype bike that was constructed two years in the past to check the geometry. That bike is wonderful to trip. It’s tremendous flickable by tight twisty stuff, but nonetheless very secure at larger speeds. I typically discuss with the dealing with as “telepathic.” It’s nearly as if the bike is aware of what to do with very minimal rider enter. It’s an absolute pleasure to trip!
• Was there something executed throughout this construct that you’re notably happy with?
With the body I needed to observe the geometry of my AK-1 race bikes from 20 years earlier, however with slightly little bit of a refresh. I pulled a lot of inspiration from Bimota with out copying something instantly. I’m very proud of the outcomes.
I additionally needed to design a tail that appeared like a Yamaha half and matched the design language of the R6 tank, but even be distinctive to this bike. I went by many ups and downs within the course of… I preferred the route, then didn’t, then preferred it once more, then didn’t prefer it. In the long run it got here out excellent and the graphics additionally labored out rather well with it.
• Is there anybody you’d prefer to thank?
And my wonderful spouse Laura for permitting this craziness to intrude into our lives!
Construct Specs
- Wheelbase: 1410mm (55.5″)
- Swingarm Size: 585mm (23″)
- Rake: 21 Levels (Sure, it’s that steep!)
- Weight: 290 lbs (with 1/2 tank fuel)
- Weight Distribution: 55% F / 45% R
- Seat Top: 810mm (32″)
- Notes:
- Uneven body design permits for bigger enlargement chambers on the correct aspect
- Rear suspension geometry primarily based on the TZR250-3XV design
Comply with the Builder: BARF (Bay Space Riders’ Discussion board) Construct Thread
