The DR-Z400sm is not at all competitive against the CRF450s and such, but I doubt competition capability affects sales outside of sportbikes and MX bikes (I’m not familiar with trials, so let’s leave that arena to you). The DR-Z400sm isn’t marketed as a competition sumo. Anybody serious about sumo is just going to convert a 450 or buy a Husqy or KTM. However, for the non-competing enthusiast, the $6500 DR-Z, pre-packaged with axle sliders, peg sliders, sportbike wheels and street tires, inverted forks, and other things is a slamming deal. It’s also street legal. As exactly that–a non-competing enthusiast–I can ride the bike off the lot without spending another dime.
Take the Yamaha WR450, for instance. It’s $7500 MSRP, and is still carbureted. On top of that, it has dirt bike wheels and tires and a dirt bike gear box. If you’re not competing and want to ride on the road (as WeaponZero obviously does), you also need to add mirrors and signals, and it still has all the dirt-focused fenders and plastics, etc. that you were complaining about in the DR-Z. Already we’re talking about at least $1500 in mods to get a street-going bike. Not really a bargain for an extra 50ccs. The Honda CRF450X is even more expensive at $7900, and has all the same pitfalls.
Even the Husqvarna SM 450 is $8000, still carbureted, and needs mirrors and signals as well. KTM doesn’t make a supermoto bike below the 690, so you’d have to convert one of the 450 EXC enduro bikes. Those start at around $8000 as well (KTM doesn’t release MSRP, but the 2006 was $7600 and prices only go up over 5 years), and they have dirt tires and again, no mirrors and signals.
All of these bikes also have about 20-35% less fuel capacity than the DR-Z. The DR-Z also has a TON of aftermarket support have been around in S and E versions for quite some time, can gain about 10 HP (a 30% increase) and lose about 20 lbs with about $1000 worth of mods, and stills comes out cheaper than a pre-sumo-conversion 450cc trail bike. There’s a reason that they’re very popular, and at least around here, every Suzuki dealer I’ve been to has two to four of them in stock. Also, as a DR-Z400sm owner in Seattle, I can assure you that the fenders pose no problem for wet riding.
So really, the DR-Z makes perfect sense, both practically and financially, for people who want a street bike. Granted, that’s not you, but no need to rain on another’s parade. Yes, there are substantially lighter and more powerful bikes out there, but they cost more proportionally and take a lot more work to get on the road.