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Riding Speedwerks’ RGV500 Two-Stroke Masterpiece

Iconic power meets an inspired chassis

By the seventh turn at New Jersey Motorsports Park this Suzuki RG500/250 hybrid and I were done warming up. “Let me go,” it whispered, “you know who I am.”

A 1980s engine in a 1990s chassis
A 1980s engine in a 1990s chassis but with the fit and finish of a modern production sportbike: Speedwerks RG/RGV hybrid.thesbimage.com

In seven turns I was indeed comfortable with what Steve Long and Dave Trotter at the Speedwerks had created: a mid-1980s RG500 engine, built by Rick Lance of Lance Gamma, in the amazing chassis of an early 1990s RGV250—wildly modified and well set up by Speedwerks. Long had mentioned this build to me at the New Jersey AHRMA round and my interest was immediate; I told the builder I'd ride anything he ever made, especially a 500 in a 250 frame.

hybrid Gamma
“This is what Suzuki should have built” ran through my mind as the hybrid Gamma tracked straight and true over the bumps out of 3C and wheelied over the hill to T4 on lap two.thesbimage.com

A Brief Smoker History

My father passed his Walter Wolf 500 Gamma to me and it had Lance Gamma mods. I tested and reported on the RGV250s for the magazines when they were brand new. In 2000, my brain was warped by the motha of all Suzuki 500s when I lapped Phillip Island on Kenny Roberts Jr.’s championship-winning RGV.

Kenny Roberts Junior’s RGV500
Riding Kenny Roberts Jr.'s RGV500 in 2000.Cycle World
Walter Wolf Gamma
My dad’s Walter Wolf Gamma…all stock except for Lance Gamma pipes and jet kit. My dad’s two-stroke history started with a Kawasaki H2, then a Suzuki GT750, Yamaha RZ350, and finally this Gamma. So, yeah, it’s in the blood.Nick Ienatsch

And keep in mind that I raced a TZ250 in AMA and now campaign Rusty Bigley's Spondon TZ750 with AHRMA (and have my own street-legal TZ750), so I've been on both sides of this Gamma's 500cc displacement. I add this history because there are many two-stroke aficionados in this country with ring-a-ding backgrounds and they need to know this Speedwerks 500 streetbike is sensational, a brilliantly rideable assembly of power and handling. So, yeah, I was ready to push hard after the first lap despite the fact that this was the first 2.5 miles this project had been ridden. "Just roll around and bed things in, scrub the tires, make sure things work," Steve said as I rolled out. Good in theory, tough in practice. Things were working.

Let’s be honest, production 250 two-stroke streetbikes are slow. They have beautiful handling with precision that is unimaginable until you ride one; the power delivery is exciting, but there’s just not enough of it. Steve Long knows this fact intimately so when Dr. Jeff Martin contacted him about sliding a 500 Lance Gamma engine into an RGV250 chassis he took the challenge. He’d already built plenty of aluminum-chassied 250s and always felt the chassis just begged for more power.

My dad’s Walter Wolf, on the other hand, has enough power to keep your attention, but spindly wheels with low-tech brake and suspension components don’t deliver the handling confidence one might want on a 500cc stroker. Many 500 Gamma owners choose to modify the running gear after a quick sprint down a curvy road because the engine’s power production begs for a chassis to match. I’ve enjoyed many modified 500 Gammas, but this hybrid is the best I’ve ridden so far and it proved itself under the relentless demands of NJMP’s Thunderbolt racetrack. This wasn’t a quick spin up a curvy road, this was 30-plus minutes of “let’s get it on.”

Truly Integrated

We’ve all ridden bikes with trick parts bolted on that aren’t particularly impressive or rideable. The secret to bikes like this, machines that feel instantly familiar, is not the parts involved but the integration of those parts. Guys like Long and Trotter, and Carry Andrew for instance, produce instantly rideable motorcycles because they’ve seen it done right and wrong for years. I’ve had the pleasure to ride and race machines from guys like these and the experience is always the same: It’s easy to haul ass the moment the tires are warm.

Suzuki RGv250
A Suzuki RGV250 fits my 5-foot-8-inch frame perfectly and hanging off a light bike really affects direction change. Here we’re working through 3B for a run out of 3C and up the hill.thesbimage.com

The impression that hit me early is the one that stays with me: This Gamma hybrid feels like a production motorcycle. No, not a vintage production motorcycle, but a modern sportbike with very few weaknesses in form or function. For instance, I’m not sure how the neatly integrated lighting would serve during a spirited nighttime run up your favorite canyon, and perhaps the public doesn’t want to kickstart their motorcycles these days, but that is the level of “problems” I’m left contemplating.

Long and Trotter relentlessly pursued light weight. Yes, it makes this 115-hp bike accelerate harder, but there’s also a massive effect on braking and direction changing. The scales showed this Suzuki weighing 298 pounds sans fuel, and as the lap count increased I continued to steer the bike more quickly and ask for additional entry speed, all due to the bike’s lightness and rightness. It’s also notable that a light bike is less taxing to the old journalist aboard it! Yeah, I was sweating but lightness definitely extends riding sessions.

First things first: Sorry about the sound! You will hear an angry Yamaha FZ1 because our ultra-trick digital microphone on the RGV failed right from the start. It worked in our parking-lot tests and then abandoned us on the track. Sorry, two-stroke fans, we'll make it up to you next time. Second: The angry FZ1 could not keep the Gamma in sight—115 hp pushing 298 pounds makes lapping easy.

I certainly didn’t beat on Dr. Martin’s motorcycle because that would be wrong on many levels, but during the second session with other bikes on track, this Gamma and I jelled into a very quick pace that used the rpm, brake pads, and tires close to their very-high limits. A bit of the red haze filtered into my helmet as the bark of a four-cylinder two-stroke and unbelievably settled handling encouraged me to see how many four-strokes I could pass. I stayed out for 30 minutes. At no point did the Gamma hold me back. It delivered the precision of a Formula 2 250 but carried a 115-hp punch. Steve Long’s Speedwerks delivered what many two-stroke fans would refer to as the perfect bike.

Pictures Tell This Story Best

Stock Mikuni carburetors
Getting started: Fifteen years ago Dr. Jeff Martin had Rick Lance build a trick 500 and 1,000 klicks later it's still haulin' the mail, so Martin ordered one up for this build. Stock Mikuni carburetors offset-bored to 30.5mm feed the 555cc, high-compression engine. Rick Lance also installed his clutch-upgrade kit and Steve Long referred to the whole deal as: Rick Lance's Bomb-Diggity engine. It made 115 hp on the Dynojet dyno and accelerated the 298-pound Gamma hybrid with authority. It doesn't deliver the hit of the Spondon TZ750 (320 pounds and 140 hp) but accelerates far, far stronger than the 250 Gamma. Power was decent down low but things got furious from 7,800 to 11,000 rpm.Speedwerks
welding the bolt-on engine mounts
Steve Long and Dave Trotter go above and beyond with their builds, in this case taking extra steps like welding the bolt-on engine mounts in place. They spent a great deal of time figuring engine placement, steering geometries, and especially sprocket alignment.Speedwerks
Rear
Mark Dent (performancefab.co.uk) supplied the subframe, engine-mount kit, and exhaust system, which requires minor finishing like mount installation. "I saw no reason to reinvent the wheel with these parts because Dent's quality is second to none," Long told CW.thesbimage.com
2017 Kawasaki ZX10R forks
Yes, that is a 2017 Kawasaki ZX10R fork…resprung with 0.75 springs to work with this Gamma’s 298 wet weight.Speedwerks
one-off oil tank
A one-off oil tank is integrated into the custom Performance Fab subframe, keeping the ease of oil injection for this street-legal stroker.thesbimage.com
Brembo Racing 484 calipers
Things get even more trick at ground level with Brembo Racing .484 calipers squeezing HP Racing rotors in front. Despite running a lot of laps and pushing hard, the brakes just laughed as they provided limitless performance.thesbimage.com
Kardesign
Why hide such trickness under a stock paint scheme? Kardesign (kardesign.co.uk) put together a bunch of graphics choices for Dr. Martin, and then John Walls, the painter Long has used for 25 years, sprayed it with House of Kolor Sunset Pearl paint. No stickers were injured in the construction of this bike: all graphics are painted on.Thesbimage.com
Nick and Steve
Tyga Performance in Thailand produced the Honda RVF400 GP-T upper and lower fairing, and Speedwerks retained the RGV250 fuel tank and solo tailsection, while the fenders are carbon fiber. Why are Steve and Nick laughing? “Yeah, those four-strokes looked good when you went by them” might have been said. Could just be the effect of a great-running smoker.thesbimage.com
five-lap shake-down run
The initial five-lap shakedown run was less about identifying any issues and more about getting my brain around the corner-entry speed this bike was capable of. Yes, it got off the corner very nicely, but its placidity during the shakedown period was amazing. Long intelligently managed to balance the extremely light and rigid RGV chassis with relatively stable steering-geometry choices. We ran the Hyperpro steering damper on a very light setting due to the bike’s equanimity, even over the bumps exiting turn 3C.thesbimage.com
Steve and Nick talking
"What do you want to change?" Steve asked me after the first run. "Lower the rearsets' shifter and let's go" was my reply. Four-strokes were waiting to be passed! (A note here to four-stroke riders: Don't be offended, it's all in jest. Part of owning a two-stroke is making fun of four-strokes… It's tradition, not personal. —NI)thesbimage.com
Track session
A 30-minute session with other bikes on the track proved the quickness of this 250/500 combo as it made short work of every other bike, all four-strokes. If the 500 couldn’t outpower them on the straight, it made tens of bike lengths in the braking zones and a few more midcorner. A sub-300-pound wet weight feels like cheating.thesbimage.com
Dunlop’s 3C+
I’m a big fan of Dunlop’s Q3+, especially on lighter bikes, and despite pushing quite hard (keeping in mind my guest-rider status), the Gamma was well up to the task. As we discussed the bike at the end of a very entertaining day, and the only modification I would like to try was to raise the rear end to help the bike finish the slowest, tightest corners on the track when acceleration was squatting the rear Öhlins. Oh, and of course I wanted to race it in AHRMA Open Two-Stroke with the title in my name. Awesome bike…thesbimage.com
Steve
Steve Longthesbimage.com

Specifications

Engine

  • Lance Gamma-built 555cc four-cylinder two-stroke Suzuki 500 Gamma
  • Lance Gamma clutch kit w/ updated transmission gears
  • Stock carburetors bored to 30.5mm by Lance Gamma
  • Performance Fab exhaust kit
  • Mishimoto radiator, modified by Speedwerks
  • Full Spectrum P1 LiPo battery
  • Koso tachometer
  • Dynatek mini-coils w/ NGK wires
  • Speedwerks custom oil tank, various brackets, brake lines

Chassis

  • 1992 RGV250 VJ22 frame and swingarm
  • Blackstone Tek carbon-fiber wheels: front 17 x 3.5; rear 17 x 5
  • Supersprox sprockets
  • RK Max-Z 520 chain
  • Öhlins shock
  • 2017 ZX10R fork w/ 0.75 springs
  • IMA Italy triple clamps w/ 31mm offset
  • Brembo .484 front calipers w/ HP Racing rotors
  • Brembo RSC master cylinder
  • Brembo CNC rear caliper on Tyga hanger w/ Braking rotor
  • GP Tech thumb brake
  • Dunlop Q3+ tires: 120/17 front; 160/17 rear
  • Performance Fab subframe, engine-mount kit
  • Hyperpro steering damper

Body/Beauty

  • Tyga Performance Honda RVF400 GP-T upper and lower fairing
  • Suzuki RGV solo tailsection
  • Carbon-fiber front and rear fenders
  • Suzuki RGV250 fuel tank
  • Design renderings by Kardesign.co.uk
  • House of Kolor Sunset Pearl paint; painted by John Walls