Strange things happen in Las Vegas. Dynojet’s land-speed-record CBR600RR Honda gets stolen, for instance, only to be recovered a while later in a dirt lot just around the corner (not that there are any non-dirt lots in Vegas), thanks to an anonymous call. Their beautiful Honda is now freshly done up in pickup truck bedliner—but also sporting a CBR1000RRfork, a better shock than before and a huge rear sprocket.WTH? Actually, weird is normal for Vegas. Bedliner is the new fur for the stunt crowd, we’re told: It’s a cure for common road-rash and may absorb radar if you slap it on thick enough. As to where the fork came from, the Dynojet boys are baffled. (Has anyone seen Freddie Spencer since his ex sold all his bikes on the LV Craigslist a while ago?)
Dynojet Powersports Technical Support Manager Dusty Schaller tells the tale. “We blew up the engine in 2007 on our last Bonneville run. So, we rebuilt it, made it better, got everything we needed on it. I was going to go back in 2008, but the night before I was going to drive up, the bike got stolen—it was the only bike they took from our shop. Why that one, I have no idea. You couldn’t really part it out since everything on it was one-off. And it was so lowered you could barely ride it on the street. We had BST carbon wheels on it, and the thieves fabbed up a sprocket to fit those wheels, put frame sliders on it, made dog links to raise it back up. They really spent some time on it. Anyway, we got it back and the engine was still in good shape. Race Tech helped us with the suspension and Catalyst redid the bodywork for us. The goal was to keep the CBR600RR as stock-looking as possible. The bodywork is a mix of CBR600RR and CBR1000RR. The tail is ’07 CBR600RR, and the front fender is Hayabusa, which seems to help a bit also.”All’s well that ends well, and this tale ends with Schaller entering the 200-mph club at Bonneville last August, with an average two-way run of 206.015 mph in 650 MPS-BF (Modified Partial Streamliner/Blown Fuel). As a matter of fact, this bike was the first non-streamliner 600 to go 200 at Bonneville. “They didn’t even have a class for us,” says Schaller. “We set the benchmark, so to speak.”
“The goal was to keep the CBR600RR as stock-looking as possible. The bodywork is a mix of CBR600RR and CBR1000RR. The tail is ’07 CBR600RR, and the front fender is Hayabusa, which seems to help a bit also.”
To push the bike through the Bonneville air that fast, the little CBR makes a bit more than twice the horsepower of a stock unit, with an IHI turbocharger producing a maximum 16 pounds of boost that results in 240 hp. To deal with all that power, Carrillo rods and CP pistons are used, and the head was prepped by Vance & Hines. Otherwise, says Schaller, all is stockish.
In any case, Schaller says that power is not really the issue. “We originally ran it in 2007, and the boost was coming in so hard at the start it would just spin the tire and never recover. So, when we went back this time, we had a boost controller on it, controlled by a handlebar switch. The controller has a seven-pound spring in it, so I could start off at seven pounds to get rolling, then switch to 11 pounds, then 16 pounds of boost—so I could get some momentum, then up the boost. That worked much better.”
Naturally, with the engine working great, something else evil would have to rear its head. “Straight off the truck, “ said Schaller, “it was doing what I call a ‘snake weave,’ just back-and-forth, not like a headshake. It was like the whole chassis was chasing itself, which pretty much scared the crap out of me. We went 191. I said, ‘There’s no way we’re going any faster; I don’t have the balls to hold it open any more.’
“Luckily, Paul Thede [of Race Tech] was there and looked at it. He had these two straight aluminum bars in his truck that he pulled out, strapped to the rear tire and measured the distance either side of the front tire. The rear wheel wasn’t straight. I’d aligned it with one of those chain guides. Paul said, ‘Yeah that means your chain’s going straight. But it doesn’t mean your front wheel and rear wheel are aligned.’
“So, we got the tires aligned, let four pounds of air out of the tires, and the thing went straight as an arrow the rest of the weekend. You’d never know you were going 200 miles an hour. It’s amazing what small changes make when you’re going that fast.”
This being a Dynojet effort, the boosted bike also makes use of that company’s new Auto Tune, (tested by Cycle World in April, 2010). Using its own O2 sensor in conjunction with a Dynojet Power Commander 5, Auto Tune allows the bike to basically draw its own fuel map. In fact, the CBR used two PC5s: one to control the VP C16 juice spritzing from the lower injectors in 7-pound boost mode, the other to control the upper fuel injectors at the higher boost settings.
“We used our new Auto Tune on it, which made a big difference,” explains Schaller. “Lots of people struggle with turbos. If you’re running a straight, single boost pressure all the time, it’s not so bad. It’s when you start doing different stages of boost like we did this year that it gets tougher. We brought a boost offset into the PC5 and were able to trim our fuel curve based on the boost level. The other thing is that the air density at Bonneville changes dramatically. One, you’re already at 4300 feet, I think, and in the morning it can be 60 degrees and in the afternoon it’s 90 something, so air density can go all over the map. If you don’t have something that compensates well for all those changes, you can be chasing your tail all weekend long.
“In 2007, we didn’t have Auto Tune. We had to just log air-fuel ratio, and after every run, we’d make adjustments. That was a pain in the neck. This year with the Auto Tune, we’d look at the data after every run, and the fuel curve was good every time.”
There it is, better living through electronics, and more of it, too, since you get there faster. Dusty Schaller thinks there’s more speed in the little Honda, and the Dynojet crew is itching to get back to Bonneville to find it. Stay tuned.
