Built out of necessity, this was just going to be a nice little shop bike to show off a few things. Nick Trask, owner of Trask Performance in Phoenix, needed to build a shop bike to take to all the shows and get seen with his turbo setup. It all started with a stock '07 FLHX that was stripped to the frame.
Once Nick had the raw frame on the lift the team went to work on chopping and dropping the seat height a few inches, then worked the frame to achieve the desired rake and trail for the look Nick was after. The bike was getting a new set of wheels: a 26-incher up front and an 18 out back. So Nick needed new fenders. A call was made to John at Sinister Industries for some fenders and a new fairing. Once the fenders were on the bike, Nick wanted to trim down the front fender and extend the rear just a bit. The bags were re-worked and stretched, then Nick added a set of his new saddlebag latches and made sure that the dual exhaust system would have enough room and clearance. LED lights were then mounted into the rear filler panels alongside the rear fender replacing the stock setup. The side covers were reshaped to fill in the area along the frame better and provide a better looking area to paint. The outer fairing was also replaced with a new Sinister Raked Corrupt, and the inner was filled with blue Klock Werks gauges and upgraded speakers. All the stock controls found their way to the junk box as the all-new PM hand and foot controls were added along with West Cost Choppers floorboards.
The next thing was the motor and turbo system. As the paint was applied by Brian at Steel Vision and Affordable Powdercoat was handling the powdercoating, Nick and his team worked on the powerplant. Nick builds all his motors for strength and power, but keeps them very reliable. He started by welding the crank and adding a Timken bearing to the left side, and added forged pistons and valve springs along with mild headwork. Once the turbo system was set up, Nick added a larger oil cooler with an intercooler and an external wastegate with dual exhaust. This aggressive bagger runs at 9.5 pounds of boost on pump gas, producing more than 150 hp and 160 lb-ft of torque at 3,200 rpm.
As the clock expired to get the bike done for Arizona Bike Week, the sheetmetal was coming back to the shop finished in a matte black with graphics of some of the coolest looking evil skulls and sexy dead chicks. Once all the painted parts were back on the bike, Nick could see just how well all the lines came together and how its stance was "dead" on. Its show tour started with Nick's hometown of Phoenix, and it was a showstopper. It was just what he set out to do: slightly offensive to some, and amazing to others. He said he could send out a dyno sheet to show just how offensive it could be; 150 hp should offend every cop in Arizona.
Inside the Turbocharger
The engine produces exhaust gases that exit via the exhaust ports of the cylinder head. These gases flow through the exhaust manifold into a turbocharger unit as the exhaust gases enter the turbine housing. The velocity of the exhaust gases spins a turbine wheel. As this turbine wheel begins to spin, it turns and drives a common shaft. This shaft has the compressor wheel on the other end. The compressor stage of the turbo begins to suck air in as the compressor wheel begins to spin. The compressor wheel spins faster and faster and the air becomes compressed, charged air. The faster the wheels spin, the faster the shaft speed, thus the greater pressure.
From the compressor stage of the turbine, the charged air exits at a greater velocity and makes its way to the intake side of the engine, through an intercooler. An intercooler is a huge heat exchanger, which is like a radiator, but for air. It cools the intake air temperature as it enters the engine. As more air is forced into the motor, an additional amount of fuel must also be added. The amount of fuel must be proportionate with the amount of air that is supplied to the motor. More air, plus more fuel, equals more power.
A turbocharged engine revolves around one central idea, and that is boost. Boost is defined as the increase in manifold pressure above atmospheric pressure. Boost is a gauge measurement of a turbocharger compressor's discharged pressure. This basically means the value of charge pressurized air coming out of the turbocharger. The higher the boost, the more air will be forced to the motor; therefore, more horsepower will be made. Boost is measured in pounds per square inch (PSI).