Robbins currently races in the NHDRO drag series, competing with the ‘King he built-up primarily for that purpose. His experience drag racing started on four wheels, when in 2007 he took a 1980 model year Corvette and boosted it to 500 horsepower and 500 lb-ft of torque. The experience was exhilarating, but according to Robbins, he “needed more power.” He also knew that it all would be a whole lot more fun on a bike.
Robbins grew up on motorcycles and started to ride before he was 10 years old on a dirt mile track built by his father. His love of motorcycles grew over the years and he has owned many bikes during that time, but when his search for a drag bike began, he went where so many have gone before and started looking at Suzuki’s Hayabusa. The aftermarket options and the high-level of performance offered by the super-powered machine were alluring, “but then the B-King came out and I had to have it. It was more my style,” says Robbins.
He bought a black B-King and took it immediately to the races. He continued on for more than two years before buying a second, so he could have one for the street as well. “I enjoy riding the B-King on the street more than any bike I have or had,” explains Robbins. “I have been on the B-King for 12 hours on trips. I’ve been to Key West twice from Wisconsin.”
Now with a bike designated specifically for racing, Robbins set about creating more power in the already hulking 1340cc machine. With help on the ECU from Justin Woolich, who hails from Australia, Robbins was able to create his own timing, fuel and secondary maps. He removed factory limits from the ECU and then bolted on a host of aftermarket parts to get himself, a 218 pound, 6'1" suited rider, and the B-King into the 9.25-second range for the quarter-mile.
It was a positive start for Robbins, but then he got word from a friend who lives near the Texas Mile that a number of B-King riders had come into town thinking they’d easily get the 200 club, but consistently fell short. He did some research and found that a fine-tuned stock B-King engine, trained rider and optimal conditions would likely yield speeds from the 170s to the 180s in the mile. Getting over 200 mph would take some creativity and work, but it was a challenge Robbins was more than happy to accept.
After conferring with engine builder Chuck Bower from RC Performance in North Carolina, Robbins decided to go “with a 1565cc large bore build. It was a first generation block bored to accept 85mm JE Pistons. I stroked the crank to 69mm and came up with a 14:1 compression ratio. I added a five axis CNC large bore cylinder head porting, new cams, a race cut tranny and micro polish. Carrillo rods are in there to take the higher power and nitrous operations and I added a heavy-duty Vance & Hines cam chain and solid roller adjuster. ARP bolts hold everything together.”
He also needed an upgraded fuel pump, so went with a modified Audi Bosch that “would sufficiently supply fuel up to about 400 hp,” continues Robbins. “I modified the fuel system and installed this pump directly into the factory location within the fuel tank. I installed a full-on Brocks header exhaust system and my own type of ram/cold air induction and tuned accordingly. I created my own timing curve, primary and secondary fueling maps and then adjusted rev limits and converted the pair circuit to actually control nitrous operations. This circuit allowed me to program the stock ECU to activate NOS, add fuel and pull timing during operations.”
On the dyno, the new B-King engine pumped out 238 hp and 140 lb-ft of torque. The NOS shot added another 48 hp and topped out the torque at 168 lb-ft. He put a fresh set of Dunlop Q2s on the front and rear after installing a longer swingarm, which gave him a 67-inch wheelbase, and headed to Texas.
Robbins drove the track in his truck the night before runs started on Saturday and found the straight to be rough, with “washboard type buckling at certain locations.” Robbins claims, “I would not have made the trip if I knew how rough it really was.”
His first two passes on Saturday were done sans nitrous, and he achieved a 185 mph and 187 mph. There was potential for his second run to be even faster since he posted the speed in sixth gear at 9950 rpm. “I was going to change to lower gear to get rpm close to the 10400 mark where peak horsepower is on my bike,” he admits, “but the lines were about three hours to make a pass and I wanted to spray.”
On his third pass he cracked the NOS, which had a bottle pressure of 1200 psi thanks in part to help from the scorching Texas sun (during dyno testing the cold bottle pressure was at 600 psi). He hit the arming switch at the three-quarter mile mark, where he assumes he was already in the mid-180s. “I think the front lifted a bit,” he says of the extra dose of power, “it pulled super hard. I think that might have been around a 70 hp shot with the extra bottle pressure. I could barely hang on. Anything over 180 on a B-King is all just blurry colors. Just reading the tach is hard; takes about two seconds looking at it to get an idea for these old eyes.”
That run he reached his rev limit at 11,200 rpm and thought he was well over the 200 mark, but the official pass rang in at 197 mph. He couldn’t hear the bike at those speeds and says the wind buffeting is “insane on this bike up there. I was surprised that the headlight and trim stayed on. I didn’t tape anything for aerodynamics.”
After investigating, Robbins decided the wheel was breaking loose, so he put a 41 tooth sprocket on and lowered the tire pressure to 19 psi.
Sunday came and just before his pass officials notified him that the mile marker had fallen down, which “is the last black blur when you need to shut down.” He repeated the process from the day before, hit the NOS at the three-quarter mark and the run felt smooth. He thought he’d gone too far down the track and put on the brakes, but when by the time he’d slowed enough to see where he was it became frustratingly apparent that he’d slowed too soon. Despite the hiccup, his ticket came in at 200.5 mph.
He wanted one more pass though, and had to wait four hours to get it. By that time the mile marker had been put back up and the sun had warmed his bottle to 1100 psi. The wheel broke loose this time near the 200 mph mark but he was able to improve his run slightly, registering at 200.9 mph.
“I didn’t have the strength to make a third pass that day,” admits Robbins. “I felt like I got beat by a gorilla. The drag on a B-King is incredible and this speed may just be about the top end for it.”
Though he had the bike geared to reach up to the 220s, he had accomplished his goal of surpassing the 200 mph mark and made the record books. Not a bad way to spend the weekend.
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Source: MotorcycleUSA (Wilson, 7/23)
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