Derbi: Big Fun in Small Packages

story by Gabe Ets-Hokins, Created Mar. 19, 2005
What is the future of motorcycling in America?

If you were to guess from the kinds of motorcycles on our roads today, you might think the future will reveal more powerful and larger displacement sportbikes, dirtbikes and cruisers every year, until a literbike is regarded as a learner's tool and any cruiser under 2000ccs a "chick bike."

It's easy to hold this perspective in the USA, but a visit to a few other nations might change this view. In China, for instance, a 250 is seen as a seriously big bike suitable for the police or privileged Party apparatchiks. Japan requires a special license for just about every displacement category over 50cc, with anything over 400cc difficult and expensive to get.

In Spain and other European nations, restricted (meaning power output is limited so the vehicle can't exceed 30mph) 50cc motorcycles and scooters are legal to ride by youths as young as 14. This has created a lucrative market, giving rise to some fascinating machinery that is unavailable in the USA. 50cc dual sports, super motards and incredibly high-performance sportbikes with disc brakes, adjustable suspension, alloy frames and full fairings are in the motorcycle shops there from many manufacturers.

Those are 50cc GP Racers. The bikes were capable of over 100 mph.One of these manufacturers is Derbi SAU. Founded in 1922 by bicycle racer Simeon Rebasa Singla near Barcelona, Spain, Derbi started building motorized vehicles at the end of WWII and is now Spain's largest motorcycle manufacturer. Derbi has a long and rich tradition of building competitive race machinery, and has garnered 84 motorcycle Grand Prix trophies.

Since most of these victories were in the 125 or smaller classes, Derbi really knows how to make a lightweight, powerful two-stroke engine. The basic 50cc air cooled scooter engine has powered thousands and thousands of ring-dinging tiddlers all over Europe.

Derbi's relationship with the US market has been on-again and off-again for the last 40 years. Rental companies loved Derbi's mopeds in the 70's, as they made a model with collapsible pedals that could be rented to non-licensed riders, as well as other models popular during the 70's moped craze. However, Derbi never fully established itself in the U.S. as a series of small importers would bring in a few containers at a time and then abandon importation of bikes and parts.

This is a formidable machine whose profile fills Aprilia RS50 racers with dread.One of these importers started selling Derbi's GPR50 in the mid 1990's with some success. This machine is very sophisticated for such a small bike, with a liquid-cooled, reed valve two stroke engine replete with expansion chamber and electric start. The bike has a full fairing and 16" wheels, and is actually larger physically than a TZ125 roadracer. These units were being sold at the dealers with 70cc kits installed and can achieve almost 65 mph with the standard exhaust.

This is a formidable machine whose profile fills Aprilia RS50 racers with dread.

In 2002, I was working at the Derbi dealer in San Francisco when my wife decided she missed her motorcycle enough to want a scooter to ride to work. She wouldn't need a particularly fast scooter, just something light and manageable, with room for her helmet under the seat.

It's fast for a 50cc, but the Atlantis is still slower than a CBR 600 F2. Photo by Clint Graves.I figured all 50cc scooters would probably be slow, but if that's what she wanted, I'd get her one! I guessed something like a Yamaha Vino or Zuma would be the best value, but since I was working for a Derbi dealer, I should try one of our products out. We had a pretty light-blue Atlantis with some scuff damage from a test-ride gone awry that my boss offered to me for a bargain-basement price. I put it on my credit card and prepared to ride my new scooter home on side streets so I wouldn't become an SUV hood ornament.

I shouldn't have worried. The scooter warmed up in 20 seconds, and shot out into traffic when I wound the throttle to the stop. Soon I was rocketing out down Fell street at an indicated 55 miles per hour! The brakes weren't the strongest, as you would expect from a miniature 190mm disc, but the rear drum was surprisingly effective, so as long as you weren't two-up, you could stop pretty well. The 49 inch wheelbase and 12" wheels gave new meaning to the word nimble. After a while my wife started to complain that I was riding our new scooter more than she was, even though I had two or three bigger motorcycles in my garage at any given moment.

OK, 1, 2, 3: Crash!My excitement peaked in the fall of 2002 when I heard the new 50cc Supermotard from Derbi would be sold in California. Based on the Senda dual-sport, the SM50 has 17" wheels with sticky tires, a 260mm disc front brake with steel brake line, a twin-spar steel frame, and stout suspension. The 50cc liquid-cooled two-stroke motor is rated at about 8 hp by the factory, with a 10,000 rpm redline.

My first ride on the SM50 was incredible- it was the lightest, best-braking, best wheelie-ing, best handling motorcycle I had ever experienced! No wonder 125 two-stroke road racers go on and on about how great their race bikes are. There is no substitute for light weight to maximize motorcycle handling, braking and acceleration.

A friend of mine was looking for a fleet of motorcycles to start a Supermotard training school, and I told him about the SM50s. He was interested, and purchased the first two we got to test out.

This is OK to ride on the street in California. Don't you love loopholes?Peter hauled the two Derbis from his house in his van, and showed them off at the Arco station where our local Sunday morning ride starts out. Another friend of mine put his personal bike in the van and boarded one of the SM 50's I got on the other, and we joined the ride mid-pack to assault the first section of the ride on our 8 hp "toys".

The first section of our Sunday Ride is a gnarly, bumpy stretch of pavement along the cliffs of West Marin north of San Francisco. Horsepower is a liability on this piece of road, and the fastest riders by far are on beat-up dual purpose and Super Motard machines. We only had 8 HP, but on a motorcycle that's half the weight of the next lightest streetbike, it's enough to go at a good clip on slower roads.

My friend Justin acclimated to the 180-pound two-stroke right away. Following him up the hill, I watched as he "experimented" with the back tire's adhesion limits by going into a wicked slide from which he easily and expertly recovered. He then just took off out of sight, as I was not quite confident with the dual sport/Supermotard riding style. I fell to about 1/4 mile behind him and held my position, pulling up at the first rest stop a few minutes behind everybody else.

There's 15 of these being sold in the U.S. this year, and then we'll loose sight of Derbi for a while.The SM 50 was fantastic to ride. It is only lacking for power on uphill sections and in turns over 40 mph or so. It is slide-able and controllable like nothing else I've ridden.

The next 25 miles of coast is much faster: smooth, flowing turns that are banked and comfortable to ride at triple-digit speeds. This meant I would be left behind, but we saw another rider coming from the north, frantically signaling there was CHP ahead of us. Everybody slowed to 55: the Derbis top speed! I laughed and had fun racing the bigger bikes into the tighter turns.

After breakfast, we started an impromptu 1/32 mile paved flat track race. Two of the grizzled old Ride veterans took the pair of little bikes and raced each other around and around the parking lot, sliding into the turns sideways and passing each other with inches to spare. The little bikes were the greatest thing these guys had seen in a long time!

Listen up, students. You can only crash 20 times a day before you have to put down another $50 deposit.I haven't had so much fun on two wheels since I quit roadracing. My friend Jeremy ripped through the turns ahead of me and I struggled to keep up, sliding my boot through tight turns, sliding the back tire occasionally, passing cars and bicycles with inches to spare. The tires were sticky, the front brake is insanely powerful, and the spring rates are too firm, if anything.

By the end, I didn't want to go home!

I learned more about traction and motorcycle handling dynamics in a morning than I learned my whole first 5 years of riding. I got home and took my old FZR out- I was able to apply the stuff I learned instantly and felt smoother, faster, and more confident. The SM 50 is an amazing teaching tool.

Page 2My friend Peter Mars purchased ten more of the SM50s and started Rocket Ranch, a now-closed training school that used several venues to teach Supermotard riding to the motorcycling public. I told him that if he bought 12 bikes, I would have to buy one as well, which I did.

Rocket Ranch was an amazing amount of fun. Peter would use an existing Super Motard facility like Stockton's Motorplex, sometimes with and sometimes without a dirt portion. If there was no dirt portion, the riders would use a dirt lot by the pits to teach dirt skills like sliding into turns. On the pavement, Peter would teach the fine art of "hacking" the bikes sideways into both left and right turns, as well as less useful (but insanely fun) skills like wheelies and stoppies.

And then we wire Mr. AllCaps into a Motard for some wheelie instruction...But the fun would begin by mid morning, when the track was open for practice. When 12 riders are on a go-kart track on identical 50cc motorcycles, the differences in rider's skills and abilities become instantly apparent, and the dicing is incredible. On such a light bike, at such low speeds, you can ride around and around the track for what seems like hours without tiring, trading positions with your riding buddy as you draft and make ridiculously close passes over and over again.

Well, if 50cc is fun, than a 70cc bike should be 40% more fun, right? I decided to find out and fitted my Derbi with a MetraKit 70cc top end kit. Supposedly good for 18 horsepower, the special head, piston, cylinder, carburetor and exhaust actually put 15 hp to the rear tire when it was all bolted together. At about that time I sold my FZR600, so I decided to use the Derbi as my sole street bike.

Two-Stroke Tuning:
The sound of two-stroke motors being revved over and over is the standard soundtrack in the pit areas of just about any road-racing event in the country. Racers would stand by their bikes, twisting the throttles with serious looks on their faces. They would then engage in endless discussions about plug chops, jet sizes, needle positions, humidity and all kinds of other, equally thrilling topics.

Because of this, I always assumed tuning a two-stroke engine was a mysterious black art requiring years of apprenticeship and study to understand. But as soon as my SM50 was broken in, I wanted to add more power- I don't care who you are, 8.5 hp won't entertain you forever! However, I am kind of an idiot when it comes to mechanics, with a short attention span and attention to detail that makes a short bus full of Special Education students look like the Rand Corporation.

Luckily for me, the main manufacturers of hop-up kits for scooters and small motorcycles design them with hyper-active teenager in mind, so everything is included- cables, gaskets, air filters, etc. The instructions are usually translated two or three times before they make it to English, ("Fitting carefully the gasket so to breaking it!") but I was able to swap the top end of the motor in under an hour, and it fired on the second kick.

However, getting the parts on the bike is the easy part- now you have to figure out how to optimally set up the carburetion for your engine and application. To do so, you have to develop an understanding of how carburetors work, and what adjusting the screws, needles and jets will do. There are plenty of books and article available, but you have to experiment a little to see what works.

Tuning a two stroke in the pits of a racetrack is like barbequing- all of a sudden everybody is standing around your bike, giving you conflicting advice. The horrible thing is that everybody is right- any combination of carb size, needle clip position, air screw setting and jet sizes will work on some motorcycle, somewhere. Make sure the person giving you advice has a bike like yours!

These kits come with everything you need and can double or triple horsepower. Nothing is as fun as riding on the racetrack, but that bike was plenty of fun to ride on the crowded, bumpy, hilly streets of San Francisco. With a top speed of close to 80 mph, I had no trouble keeping up with any person, on or in any motorized vehicle. Especially in construction zones, over curbs, up stairs, or on the occasional lawn. The unrestricted race exhaust would echo up and down the street, pissing off everybody but me as I worked through the gearbox, topping out in sixth gear as I blasted down Lincoln Way towards the Pacific Ocean. Luckily, the San Francisco Police Department is a tolerant bunch, and I was only hassled once in five months when a cop car paced me on my way to work for two miles before he pulled me over to let me know I should "fix" my exhaust. I found nothing wrong with it and ignored his advice.

With great brakes and suspension and adequate power, a Super Motard is a great way to get around a crowded city.The 70cc kit was OK on the street, although it vibrated unpleasantly over 12,000 rpm and got the worst fuel economy of any vehicle I've operated short of a Crown Victoria taxicab. I thought I could get away with using the stock oil injector pump until one afternoon, when testing top speed on the 280 freeway, the top end locked up with a resigned "glurp", inducing a 70 mph rear-wheel slide, which actually is quite controllable on a bike this size. You should try it. They wouldn't let me take it on the bus, so I called a tow truck, went home and ditched the oil-pump, using a block-off plate from Team Calamari Racing and a generous dollop of Motul every fill up. Although I had two seizures (the motor, not me!) because of a mistakenly mis-adjusted oil pump, the bike's actual reliability was faultless, especially when you consider it was making about 208 horsepower per liter. Going to pre-mix solved that; although I had to carry around a messy bottle of Red Line racing oil and a measuring cup like some vintage scooter geek.

All the hassle was worth it, especially when I would pass a group of riders on Highway One on my buzzing little mosquito, leaving them wreathed in oil smoke and wondering how a 250 two-stroke was let out on the highway. I always relished being approached by one of them at a rest stop further along and having them laugh in disbelief when I told them the displacement of the black mini Motard.

With a 660 Yamaha motor, this is the biggest Derbi ever and shows the new direction Piaggio is sending the old marque. Sadly, we'll probably never see this in the U.S.A.In July of 2003 I was offered the position of California Sales Representative for the USA Derbi importer. I figured it would be easy: good product, good price, growing market for scooters and mini-motards and sportbikes, right?

Nothing is that easy, though! I called every dealer in California and managed to sign a few up, but unfamiliarity with one of motorcycling's oldest brands, coupled with the Euro crushing the dollar and cheap Chinese competition kept my sales to a minimum, and I gave up after eight months. The importer is no longer bringing the SM50 into the USA, although the scooters and an all-new GPR50 (with aluminum perimeter frame and radial-mount brake calipers) is available.

This tasty number won the design award against every other motorcycle design in 2003.The only Derbi Super Motard available in the U.S. is the rare DRD edition. The Derbi importer brought 15 of these in for 2005, and they are the most trick little bikes you'll ever see! The DRD has an aluminum swingarm with linkage, a Paoli shock with remote reservoir, and 40mm front forks with an enlarged front disc. With a beefed-up engine, this machine handles superbly and should do well in mini-motard competition.

In 2001, Piaggio (Europe's largest manufacturer of scooters and parent company of Gilera and Vespa as well as Derbi) purchased Derbi. Piaggio has made the decision to position Derbi as the leader in introducing innovative, fresh products to the youth segment of the motorcycling market. Derbi has introduced some amazing designs, such as the GPR Nude and the 659 Mulhacen, a Yamaha-powered 660cc single with 70's scrambler styling. Derbi has won design awards for two years in a row now, winning overall in 2003 with the Nude against every new model introduced by every other manufacturer on Earth. Not bad for a niche manufacturer!

Light weight and not too much power makes it easy to learn how to "back it in" and do other things which would seem dangerous on a larger bike to a novice racer.VespaUSA's spokesperson told me that Piaggio suspended further imports of Derbi into the U.S. and has no knowledge of any current plans to bring the brand into this market. This is a shame, as there is demand, if a small one, for small-displacement high-performance streetbikes, as evidenced by huge sales of cheap "pocket bikes" and the immense market for mini dirt bikes like the Honda CRF50. Derbi's products are advantageous because they are reliable and meet the requirements to be legally registered as motor vehicles for highway use in every US state. In many states they are legal as mopeds, requiring no special license!

As many of our cities become more heavily trafficked and as we loose more and more of the open areas where a motorcycling enthusiast can goose a 150 horsepower street bike, small-displacement streetbikes will make more and more sense to consumers. It's almost impossible to get a ticket on a machine that maxes out at 65 mph, and trackdays and organized competition are ridiculously cheap compared to the costs of full sized sportbikes. Insurance is so cheap for sub-100cc motorcycles that it's almost free- $102 a year for full coverage on my SM50! It doesn't hurt that most insurance companies still list all Derbis as "mopeds" in their databases.

Once Upon a Time in Stockton
By: Sean "Dirty" Alexander

It took me all of 4.7 seconds to accept Gabe's offer for a day of Derbi mini motard racing. I figured if it was anything like XR100 dirt tracking, then it would be one of the best times I've ever had.

As you can see from the photos and videos, I had a hell of a good time. However, I didn't exactly enhance MO's reputation with the locals when I rode Gabe's full-race 70cc racebike to lunch. Needless to say, the Stockton P.D. wasn't amused.

Sean wakes Stockton's dead, while enticing patrolman Fife out of the donut shop. The Stockton Motorplex is your typical kart track, with continuously linked turns of varying radii and little in the way of real straights. The course rewards high corner speed and favors bold overtaking maneuvers. If you watch the onboard video I shot following Gabe, you'll notice the close-quarters arm-banging typical of mini-moto racing. However, with the emphasis on preserving corner speed and the quick (read twitchy) handling of these bikes, crashes do happen. I remained mostly upright for my visit, but if I was to decide to become a pro mini-moto racer, I'd surely be replacing leathers and helmets on a regular basis.

My recommendation: If you have the guts, ask your local Kart track if they have a mini-moto class. Then, go tell your wife "They're just little playbikes honey" When she picks you up from the ER, tell her "I need a bigger bike dear, they're much safer." Viola! You have just tricked your spouse into letting you race real motorcycles. -Sean

So if you're worried about busybody politicians and community leaders deciding to take your toys away, chill. Even if the "Safety Nazis" came tomorrow and declared that motorcycles over 100cc were verboten, we'd still have fun. Because my experience with Derbi showed me that fun will always result when you add two wheels and a motor, no matter how small that motor may be.

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