Moving up the engine, the twin-crank layout not only eliminates piston side-thrust, thus substantially reducing friction and wear, and allowing use of a shorter-skirted, lighter piston which reduces reciprocating weight and allows higher revs (Baindl's twin-crank BMR revved to an amazing 12,000 rpm quite safely, an incredible piston speed for a 750cc single, but promotes greater mixture turbulence via increased piston speeds. And thanks to the unique design of the Apfelbeck head, whose vertical inlet ports curve as they approach the valve, the mixture is presented for optimum combustion effect, offering ideal burn characteristics which not only aid power delivery, but also help reduce emissions, says Baindl (who's had the help of leading Swiss tuner Willi Rufenacht in developing all his twin-crank engines, as well as electronics wizard Ewald Mayer in de-bugging the diesel version, and Dr. Werner Bauer at Munich's University of Applied Sciences in refining the design). But, that begs the question: Why a diesel? Lutz Lester explains.
"Phillip Hitzbleck of Neander had the copyright for a very famous German comic figure called Werner," explains Lester. "Werner is a free-living biker who's always in trouble with police, drinks beer and likes playing with motorbikes and engines. He's a cult figure in Germany. There were a couple of hit movies about him in the 1990s, and there've been Werner party events with up to 250,000 people attending. But in '99 Phillip Hitzbleck wanted to lead the brand name of Werner to another level-for example, making a TV series, or holding a new bike event in the north part of Germany over three days with music, drag racing, dyno shootouts, things like this. Anyway, to promote this we had the plan to take the Werner theme to MotoGP with our own bike, but we decided, if we go racing, we must do it with something completely new, and then we heard about Rupert Baindl's twin-crankshaft MotoGP twin-cylinder engine. This sounded perfect, but we couldn't find enough partners for the GP racing program, so then Rupert said, 'Why don't we bring this engine to the street as a diesel engine? This could be the first turbodiesel engine worldwide to come in a motorbike.' So in 2002 Phillip decided to leave the Werner company, put in his own money to restart Neander, and bring all the people together in order to create a production turbodiesel motorcycle anyone can buy. Now you're about to ride the result!".
Slinging a leg over the Neander Turbodiesel's low 25.5-inch seat, which is relatively plush even if the passenger pad on the back mudguard is little more than a token perch, gives no hint of the surprise in store when you press the starter button on the right handlebar. Reach behind your right leg for the ignition key, turn on the fuel tap as the pump starts buzzing, thumb the starter button (no need to preheat as on old-generation diesels), and get ready for a shock. For this is a powercruiser Not Like the Others-it's not just ready to rumble the moment it hits the highway, it does so from the moment the beefy starter motor combats the 16:1 compression to crank those massive 108mm-bore pistons, persuading the twin-crank four-con-rod parallel-twin turbodiesel motor to light up. The Neander is uncannily still, both at idle and on the go, however hard you rev it. As in, no vibes!
Select bottom gear and feed the light-action clutch out slowly to move away, and though the Neander picks up pace perfectly smoothly, there also isn't a huge amount of surge until the tach reading on the MoTeC dash shows 2000 rpm or so and the turbocharger starts to do its stuff as the boost pressure builds. There's a delicious surge of liquid power from then on up, with the torque curve peaking at just 2600 rpm, but then staying practically horizontal until the 4200-rpm power ceiling, when power and especially torque tail off quite steeply (though Baindl says they've revved the motor out to 7000 rpm safely). But what you musn't do is let the diesel engine's deceptive clatter con you into thinking that you should just rumble around everywhere at low rpm. You can do so, of course, and this is a perfectly aimiable bike to plonk around city streets on, but then you'll be sacrificing the "sport" part of the sport-cruiser package, because the turbo'll be off boost. When you persuade yourself to crank 'er up, the Neander comes alive to the sound of a faint whistle from the Garrett turbo, which you can just make out above the engine's subdued but still unmistakeable diesel clatter, delivering fast, forceful acceleration in spite of the bike's hefty 595-lb. dry weight of the kind which makes you glad you have that meaty rear tire-at least for straight-line work.
But maybe the biggest surprise once you've adjusted your mindset to accepting you're riding an oil-burning powerbike, is how fast this diesel motor gains revs. Coupled with the relatively short span of power and especially torque, this means you'll find yourself using the six-speed Aprilia gearbox much harder than you might have expected with a supposedly humble diesel, if you ride the Neander like the sport-cruiser it undoubtedly is. I regularly saw 100 mph/160 kph at just 2820 rpm during my afternoon road rumble around Bavaria, and thanks to a reasonably rational riding stance I wasn't blown off the back in achieving it, so figure this is a genuine 240 kph/150 mph turbodiesel mile eater in real-world riding. That's to be expected from something Made in Germany, the land of autobahns-but in both that country and everywhere else, the Neander would make a very suitable basis for a long-distance tourer, with its frugal fuel economy, awesome torque, and zero vibration. The Turbodiesel is not tiring to ride at any distance, and the dry-sump engine's relatively low C of G means it's also quite a relaxing handler, that takes fast sweeping turns or tight hillside hairpins in its stride, though you can't forget that rangy wheelbase in a hurry.
Really, the only downside to this thoroughly avant-garde diesel engine package is the noise it makes, which frankly isn't very pleasant-especially under full load, when the level of clatter rises quite significantly. This is not a bike you're going to want to bring home late at night if your next-door neighbor has even remotely good hearing, though I suppose you can say the same thing about a Harley with a Screamin' Eagle pipe. Anyway, the issue isn't so much about the engine itself being mechanically noisy, more that the turbodiesel tune simply isn't one that sounds at all melodic or even very sophisticated when you're actually riding it, especially compared to conventional bikes costing one-tenth of the Neander's heady sticker price.
Diesel technology has advanced so much in the past 10 years, not only thanks to turbocharging, but also due to variable nozzle geometry, and especially the evolution of the common rail system, such as found on the Neander. By any standards, this bike is a surprise-not only for its unique mechanical format, but also for the effective manner in which it applies the benefits of diesel development to a motorcycle.