Colin White’s 421cc Cheetah Cub LC…
In 1980, Yamaha introduced the RD350LC (Liquid Cooled) as the successor to the air-cooled RD400, along with a 250cc version aimed at the British learners’ market. The “Elsie” quickly became a favorite of power-hungry tuners and two-stroke aficionados:
“For riders looking for high performance on a low budget, no other bike came close. With a 110mph top speed, wheelie-popping acceleration and racetrack credibility, the “Elsie”…was the bike of a speed-crazed teenager’s dreams.” -Roland Brown, Hagertys
In 2020, MCN published their own retrospective on the beloved LC:
“Arguably the most loved and inspirational Japanese bike of all – Yamaha’s RD350LC – went on sale for the first time 40 years ago…the abilities of the 47bhp stroker twin are now the stuff of legend…” –MCN, 2020
The 250 version was no slouch either. Legend has it, the riotous RD250LC single-handedly spurred new legislation that limited UK learners to 125cc machines from 1983 onward!
However, as two-stroke street bikes died off in the years to come, a growing contingent of shed builders and tuners began developing “hybrids” — Yamaha RD specials that melded the nostalgic sound, scent, and power of a modified two-stroke engine with updated suspension, brakes, wheels, and more. Similar to what we think of today as restomods, but highly focused.
Today’s hybrid comes our way from Colin White of the UK, who’s owned the bike for 26 years!
“It’s only the fourth bike I’ve owned — the other three were also Yamaha RD’s (two 125’s and another 350 before this one), so it’s fair to say I’m a Yamaha 2-stroke fan!”
There are a lot of hybrid RD specials in the UK — the Hybrid Club is dedicated to them — but Colin wanted a bike that would stand out from the crowd:
“I wanted to build a single-minded high performance road bike, and as it’s such a commonly built bike in the UK, I wanted to try to do something that didn’t look the same as anyone else’s bike, I wanted to try to do a few bits that no-one else had!”
It took him years to assemble all of the parts he wanted. Highlights include the one-piece tail unit and solo seat made to his design, bespoke subframe and braced chassis, Ducati 916 forks with custom yokes, 320mm discs with six-pot calipers, Dymag magnesium wheels, Spondon swingarm, and titanium fasteners throughout.
The engine is now a 421cc with a TSS crank, Cheetah Cub barrels, Air Stryker carbs, hydraulic clutch, and pipes handmade by Mark Dent of Performance Fabrications.
It’s been dynoed at 95 rwhp, and Colin says the non-YPVS power delivery gives the adrenal glands a serious squeeze:
“Riding the bike is crazy — it doesn’t have power valves so the power delivery once you hit the powerband is such a rush — the power hits all at once. Compared to the stock bike the handling is very good, it feels taut and well balanced thanks to the extensive frame bracing, more modern running gear, lighter wheels, and more modern tyres…”
Below, we talk to Colin for the full details on his 421cc LC!
Yamaha RDLC Hybrid: Builder Interview
• Please tell us a bit about yourself, your history with motorcycles, and your workshop.
I’ve owned the bike for 26 years, and it’s only the fourth bike I’ve owned — the other three were also Yamaha RD’s (two 125’s and another 350 before this one), so it’s fair to say I’m a Yamaha 2-stroke fan! I’ve got a small single garage in my garden at home with a bike ramp, which is reasonably well equipped — I enjoy spending time out there!
• What’s the make, model, and year of the bike?
The bike started life as a 1985 Yamaha RD250lc, but by the time I bought it had been converted to a 350cc.
• Why was this bike built?
I tend to modify everything I own, and so I started modifying it from the first day I owned it. Originally it was small modifications, as it was my only daily transport and I couldn’t have it in pieces for long, but after a particularly hard thrashing one sunny Sunday I managed to seize the engine and then decided to go all out!
The bike was pulled apart to be built properly — although it stayed in pieces for years, and during that time I kept buying parts for it as and when I could afford them. I changed my mind a lot during this time, but finally started on a proper final dry build around five years ago once I’d got virtually all the parts in place to put it together.
• What was the design concept and what influenced the build?
I wanted to build a single-minded high performance road bike, and as it’s such a commonly built bike in the UK, I wanted to try to do something that didn’t look the same as anyone else’s bike, I wanted to try to do a few bits that no-one else had!
• What custom work was done to the bike?
So far as custom work, there’s not much that isn’t either highly modified or a complete one-off. The frame has been heavily braced to cope with the extra power and brakes, the whole subframe was rebuilt by a local forge to accommodate the one-off single seat bodywork. The bodywork was made to my design by moulding the original LC side panels and tailpiece into a one piece unit and turned into single seat — it was something I really wanted to do, but it caused a LOT of headaches and extra work to make it work!
The yokes are one-off and hold early Ducati 916 Showa forks, with one-off CNC-machined caliper hangers, twin 320mm Brembo discs, and six-pot ISR calipers on Dymag magnesium wheels — it stops well!
The rear end is a one off Spondon Engineering swingarm, a single piston AP Lockheed caliper, and Dymag magnesium wheel.
The engine is now a 421cc with a +4 mil TSS crank, Cheetah Cub barrels, and 35mm Air Stryker carbs, as well as a whole host of other modifications including a hydraulic clutch. The pipes are also handmade by Performance Fabrications and are one of the bits most often commented on — the welding is amazing!
Every fastener on the bike is titanium to keep the weight down, and weight saving was a big part of the build throughout. The only part of the original bike is the front half of the frame (modified); other than that every single part has been changed.
• Does the bike have a nickname?
I don’t have a nickname for the bike as such, but to me all LC’s are called Elsie!
• Any idea of weight or power numbers?
I’ve never got round to weighing the bike, although I’m really curious to know what it weighs. It’s spent a bit of time on the dyno; it puts out just over 95bhp at the wheel — I suspect we could get it over the 100 mark fairly easily (it’s running standard porting at the moment and doesn’t have particularly large carbs), but as it’s a road bike, 95 is more than enough to make me grin like an idiot and get me in trouble!
• Can you tell us what it’s like to ride?
Riding the bike is crazy — it doesn’t have power valves so the power delivery once you hit the powerband is such a rush — the power hits all at once. Compared to the stock bike the handling is very good, it feels taut and well balanced thanks to the extensive frame bracing, more modern running gear, lighter wheels, and more modern tyres — it’s a real pleasure to ride when you can get a decent bit of road!
• Was there anything done during this build that you are particularly proud of?
I’m proud of most of it — particularly as it’s my first build, there are loads of little details that no one notices that I love; there are also some amazing parts on it made by people far more clever than me — but probably the one part that I feel sets it apart most is the tailpiece/rear bodywork, as it’s the only one!
There are a lot of people to thank, but top of the list are my mates Darren, Andy and Pete — without their help and guidance I’d never have been able to build it. Also RSK 2 strokes for setting it up on their dyno and the rest of the Hybrid Club boys too.
As an old RD rider I find this article refreshing. I had a Daytona special back of the day. Started with a RD 350. Chambered what a learning experience!