FLATTY: Vic Shield’s 375cc Two-Stroke Street Tracker…
By the late 70s, Yamaha’s air-cooled RD250/400 two-stroke street bikes were due for an update. In order to galvanize the supersport class, Yamaha decided to go all-out, creating a Euro-centric machine that would boast liquid-cooling, cantilever monoshock rear suspension, and other features from their highly competitive TZ race bikes:
“The successors to the aircooled RDs would be aimed at Europe, designed with assistance from Yamaha Europe and, free of US restrictions, be as sporty and innovative as possible. In simple terms, Yamaha wanted to ‘build a TZ for the street’.” –MCN
The result would be one of the most iconic performance bikes of the 1980s, the Yamaha RD350LC, along with its learner-legal sibling, the RD250LC. Soon, “Elsie” mania was in full swing. The RD350 Pro-Am championship was televised on World of Sport, where a mix of amateur and professional riders raced on identically-prepared machines, including future 500cc GP star Niall Mackenzie.
“The result was close, aggressive racing that made great TV and helped earn the LC a cult following with speed-crazed youths.” –Hagerty
Enter our friend Vic Shield of Vic’s Custom Autos, whose MZ-Yamaha “Mutant” hybrid we recently featured. Vic was one of those “speed-crazed youths” who bought a 250LC as soon as he had the money. He rode his Elsie until it blew up, then swapped out the engine for a Stan Stevens-built RD350YPVS mill — one of the first such “hybrids” of the day.
Fast forward to today, and Vic still loves the smell of two-stroke smoke in the morning. The bike you see here is his “FLATTY,” a flat track-style build inspired by none other than Kenny Roberts:
“I loved King Kenny on the TZ750, and this was what made me go the way I did.”
This street tracker is something of a Frankenbike, featuring an ’83 RD350LC frame, Honda CRF250 forks, Yamaha WR125 wheels and swingarm, and an ’82 RD250LC bored to 375cc and tuned by Floydy Racing.
Vic says the bike is as light as it looks — around 265 lbs — and a new set of Lomas pipes evened out the power delivery:
“On the dyno it was just over 70 bhp…now it’s around 65 but rides much better with a smooth power delivery, and although it looks high at the back, once I’m on the bike it sits down and handles like it’s on rails…out-handles a lot of sports bikes through the lanes.”
Below, Vic gives us the full story on the creation of his “FLATTY”…and several other smokers.
Yamaha RD375LC Tracker: Builder Interview
• Please tell us a little about yourself and your history with motorcycles.
Let’s start at the beginning.
I started riding Yamaha two-strokes when I was 15 after buying a 1978 50cc F1SE moped from an old farmer whose son had left it in his barn unloved and with a snapped throttle cable. I managed to get it going and rode it the 3 miles home, mainly off-road, by pulling the cable with my right hand and not using the inadequate front brake. I then brought a RS 100 and passed my test ASAP when 17 years old. After that I had countless RD’s: 250cc, 350cc, and the 400s, all air heads.
When I had enough money, I brought one of the first RD250LC models to have come into Kent, UK. It was about 8 years old and I thrashed this everywhere until obviously it blew up…twisted crank and melted pistons. I brought a nearly new YPVS 350 engine from a wrecked bike and took it to Stan Stevens, a well known tuner in the 90s. This engine was special.
Over that winter in my dad’s shed and living room I fitted the engine into the 250LC frame and rode that bike for a few years before my “EX” wife made me sell it towards a house deposit.
I never had another LC for years…lots of other bikes but didn’t want another LC because it would never be as good as the first one.
Roll on 25 years and I was chatting with my cousin about bikes and he said he still had all his old RD350LC’s in his shed…all four of them plus bits, most in boxes and tea chests.
A deal was struck that I would build him a bike that he always wanted and could never afford. I would have the leftover parts and we would sell two complete unrestored bikes to help pay for his and my project.
I put together two bikes and we sold these on for engine funds. Two engines were taken to my mate John Floyd (Floydy Racing) for mild tuning on my cousin Jon Cross’s bike and a race but reliable tune on my engine for the FLATTY.
There wasn’t a great deal worth saving on my parts and that’s when I decided to build a flat tracker with a difference. I loved King Kenny on the TZ750, and this was what made me go the way I did.
• What’s the make, model, and year of the donor bike(s)?
The bike’s frame was from a 1982 RD350LC.
The engine was a 1982 RD250LC.
The front forks are off a Honda CRF250
The wheels and swinging arm are off a WR125.
• What custom work was done to the bike?
- The mono shock was removed and I went for an old-school twin-shock set up.
- Bodywork / tank: RD350LC
- Rear seat unit made from aluminium.
- No lights and indicators…daylight MOT only.
- The two-stroke oil holder is a large replica Hurlimann beer can, which got the nickname HOOLIGANS in the 90s due to it making you go loony after a few beers.
- It has an R1 modified radiator — the original aftermarket job just couldn’t keep it cool.
- The carbs are Mikuni 34 power jets
- I’ve changed the pipes from Tyga to Lomas, which I modified because the power was coming in at over 8k and was unridable.
- The engine has been taken out to 375cc and has a racing ignition system, which does away with the generator.
• Any idea of weight and/or power numbers?
On the dyno it was just over 70 bhp…now it’s around 65 but rides much better with a smooth power delivery, and although it looks high at the back, once I’m on the bike it sits down and handles like it’s on rails…out-handles a lot of sports bikes through the lanes.
The bike weighs in at around 120 kilos.
• Anything else?
The bike including the paint was all done in my workshop over 6 months. Floydy Racing did the engine work and RSK 2 Strokes got it set up on the dyno.
I keep getting told that it sits up too high…after riding my cousin’s bike I felt a standard RD was too small. I’m 16 stone and 5’10” tall, so I feel more comfortable on a taller bike.
It can be dropped by using shorter shocks if I wanted, but I built it for myself and it suits me fine.
Ugly and over-complicated. Yet another “street tracker” built by someone who has obviously never raced flat track or apparently ever seen an actual flat track bike.
as a Yamaha fan I think this build was done with much TLC! have never ridden an RD but one still survives locally. going by rumour they are brutishly agressive in the powerband the colour scheme is definitely on the spot!
I kind of agree with Will, this is definitely more a “street tracker” that has some (heavy emphasis on “some”) styling elements taken from a flat tracker. I like the bike but would need to see it in motion under the owner to get an idea of the layout and proportions. Otherwise it’s a little weird and slightly ungainly. Kinda like a dual-sport with a very ensconcing “tracker” tail.
Thanks for including the startup vid, that is always appreciated.
bloody beautiful hooligan bike – as with this guy – if i could find one i would build a TZ750 for the road – soooo much fun
and its not about flat track racing, its about the smell of bel ray in the morning!
I was about ten Year’s old and started riding a mini bike with lawn mower engine end when I got a Honda XR 75 oldest brother pulled up on a Kawasaki 7503 cylinder 2stroke it truly scared the crap out of me the power band kick was crazy