It makes sense on the drag strip, but what about the street?
Stretched bikes are best known for their use in drag racing. As with many race-based trends, however, stretched bikes have also become a fashion statement, a style often applied to sportbikes to make them look cool. Why do people still do this? Do It With Dan takes a stretched Suzuki for a test ride to find out.
Altering a bike's design and geometry is nothing new. People have been doing it for years, most notably with custom choppers. In this case, the sportbike's swingarm is modified, either by a bolt-on extension or a custom swingarm, to push the back wheel farther back on the bike, and often to fit a wider wheel as well. In a drag racing application, the extended wheelbase makes it more difficult for a high horsepower engine to lift the front wheel off the ground, preserving control.
That's all well and good for the track, but why do people do it for the street? It makes sense for a powerful drag bike, but when you're talking about 600s or even 250s, keeping the front wheel from lifting under power isn't as much as a problem. In these cases, it's all about the looks. In much the same way as stretching the front of a chopper looks badass, stretching the back of a sportbike makes it look like a serious speed machine. This is similar to the automotive trends of giant spoilers, lowered suspensions, and crazy amounts of negative camber.
Some people say this absolutely ruins the bike's performance. Indeed, sending power to a more distant back wheel through a longer chain, or even transfer cogs to move the chain over to clear the fat rear tire, takes some horsepower away. The longer wheelbase makes the bike less responsive to turns as well, where handling is supposed to be one of the best characteristics of a sportbike. As Dan discovers, though, while these effects are there on the Gixxer he test rides, they're not too bad. In fact, although he doesn't plan to stretch any of his own bikes, he finds that he likes this bike with its mild stretch.
The bottom line is that when a stretch is tastefully done, it looks cool. Many people modify their bikes for no reason other than looks, and that's perfectly okay. An insane four-foot stretch on your Honda Grom may not be my particular quart of 10w40, but that doesn't mean you shouldn't do it. If it's something you like, then go for it. After all, you're building your bike for yourself, not for me, and what I think about it shouldn't matter.