Triumph Rocket III - The Gorilla is out of the Cage

Carpenter Racing’s Project Silverback – an effort to extract the maximum street-usable power out of a Triumph Rocket III – has moved from the shop to the dragstrip for some real-world testing.  And the initial results have been impressive.

“The gorilla is out of the cage!” exclaimed Bob Carpenter.

The project started two years ago when his buddy Art Dilarso, a record-setting drag racer back in the 60s and 70s, first introduced Carpenter to the Rocket III. 

“Art called me up one day and said, ‘You have to see this new Triumph I have’,” recalled Carpenter.  “He came by with it and I was really impressed.  When I saw the size and configuration of the engine, my thoughts started racing.  I knew this bike would have some awesome potential. We immediately started working on them.”

With that, Carpenter has developed a dependable performance upgrade for yet another model and brand.  With the Rocket III project, Carpenter Racing as earned some elated Triumph owners and a first place trophy at the prestigious Brute Horsepower Challenge in Daytona, FL.  More importantly he has caught the eye of the management of Triumph North America who liked what they saw and jumped on the opportunity to give support.

“We are the pioneer for making horsepower for this product.” Carpenter said of his work on the Rocket III.  “On our very first attempt we were able to produce 237 hp.  Now we are consistently over 240 hp. Not only that but the people that have these bikes say that after we work on them they are noticeably smoother running.  Hard to imagine when we more than doubled the horsepower.  I think it’s the longer duration power stroke that smoothes the motor out.”

Currently Project Silverback is moving from the development phase to the production phase and with that goes some extended street testing along with drag strip runs to get some benchmark numbers.

The dragstrip test bike was equipped with Carpenter’s standard Rocket III “240 Pack” which includes CNC Race Porting, a full-radius Serdi valve job, custom springs, titanium retainers, slip-in domed pistons and new clutch springs. The bike was also equipped with the production version of Carpenter’s new stainless steel 3-into-1 megaphone exhaust featuring large 2” head pipes.  To match all of this together the ECU is re-mapped and tuned.

For the first dragstrip test Carpenter hired rider Richard Gadson, a nationally ranked sportbike drag racer and nephew of Kawasaki factory drag racer Rickey Gadson.  Richard Gadson had never even been on a Rocket III prior to throwing a leg over Carpenter’s version in the staging lanes at Atco Raceway.

“The first run Richard stood it up in first and second gear and still ended up running a 9.78,” said Carpenter.  “We were pretty happy with that because a stock Rocket III would run in the mid-11 second range.”

The track day with Gadson ended up yielding a best elapsed time of 9.34 seconds.

“Drag racers aren’t used to this bike,” said Carpenter.  “First off they are used to the riding position of a sportbike. They have a problem finding the shifter and getting in the right position to anticipate the launch. Second I think the horsepower gets them by surprise. They look at the bike and think it’s a mild cruiser.  They turn the throttle and there is another world waiting for them.”

Carpenter installed an air-shifter on the bike so sportbike-experienced test riders wouldn’t have to go searching for the shift lever.  Gadson was unavailable for the second drag strip test so Carpenter brought local drag racer and stunt rider Marcelo "Alex" Galligani to ride the beast.

photo by Mad Max

These efforts yielded an improved elapsed time of 9.27 seconds.

“Alex is taller and heavier than Richard,” said Carpenter.  “We are excited to see what Richard can do on the bike with the air shifter.”

“We still have a lot to go but I think this bike has eight second potential,” continued Carpenter.  “The power is there to do it, I think with a little tuning and work on the riding technique we will get there.  This was only the first time out for both riders.  Once they get some laps on the bike I think we are going to see some steady gains.”

Carpenter is also working on the exterior of the bike to add a racy look and high-speed functionality.

“We are developing body parts and working with different windscreens,” said Carpenter.  “The big project is developing a ram-air system.  Right now this bike is suffocating for air and we need to address that.  As far as the other body work goes, this bike is never going to be as slippery as a sportbike but I think cleaning up the aerodynamics a bit will go a long way.”

“We are trying to get the best out of the bike and keep as close to showroom as possible,” continued Carpenter. “We want it to be an everyday rider.  But a very powerful everyday rider.”

UPDATE 11/4/2011

We went back to Atco with Alex at the controls and improved our numbers on the Silverback to 9.21 seconds at 152.54 mph. 

Although the numbers were an improvement, there is more there as the bike picked up the front wheel in the first two gears.  The thing is proving to be the beast we thought it would be.

"We are starting to see the limitations of the showroom chassis and suspension," said Bob Carpenter.  "We are making tons of reliable horsepower, now we have to make adjustments to the chassis to handle that power.  This bike is on the way to making an eight second pass."

Click here to see the Triumph Rocket III Packages

Carpenter Racing: 856-753-1555

117-A Cross Keys Rd • Berlin, NJ 08009 • 856-753-1555 • Fax 856-753-9726