Once the first speed run was over I rode the bike back to base camp for refueling and to top off the battery. I was informed that I reached 69 MPH which really had me excited :0) The crew was in good spirits at this point which really set the mood for the rest of the day.
By now the air temperature was getting into the mid 80’s which would make the turbine run less efficient. This was clearly evident as the idle speed of the engine was much greater than when the air was cooler. The up side of the thinner air was that it would pose less of a force to slow me down. However I would hardly call it a fair trade off as the engine runs hotter in the exchange.
A quick inspection of the bike was performed looking for heat warping or loose bolts. Luckily the afterburner suffered no damage from the prolonged run. The bike was good to go for another round.
The tug was fired up again and we rolled out to the start line for another go. I was sure I would be able to squeeze another few miles an hour out of her.
The Turbotug really pulled it’s weight during the event (no pun intended). All day it worked flawlessly in 90° weather and drove over eight miles moving more than 1000 pounds!!
The takeoff was pretty smooth on the second run of the day. It almost seemed as if the bike accelerated faster the farther I got down the course.
This time there was a bit more of a cross wind that caused a slight shifting in the tracking of the bike. I really did not fear any handling issues but I was sure to not exaggerate the shifting in any way.
By now the bike is really moving. It seemed as if I was gliding over ice being pushed by an unseen force. There is no vibration to speak of which is a surreal feeling indeed. However there is a definite sense of power from the engine as it roars behind you. It is really a unique feeling that is hard to describe.
I shot past the finish line and rolled back to the pits. This time it was 70 MPH which was a slight improvement. After a short break there was a third run that revealed 71 MPH on a GPS logger unit that I carried in my back pocket. The radar gun we were using also logged a momentary 71 MPH on one of the runs as well.
It seems that the air friction was going to keep me at 71 MPH that day which is a success in my mind. However I do feel that the warmer midday temperatures were effecting the GR-7’s performance.
Overall we were pretty happy with the results considering that the engine was able to move 550 pounds up to 71 MPH!!!
After the speed runs were completed I decided to do a few “fun” passes with the chase van following me. You will notice (below) that the afterburner duct is glowing red. This is a pretty good indicator that the duct temperature was bout 2200° F!!!
I raced up and down the course a few times to simply enjoy the ride and boy I did :0)
The only disappointment was that I did not get to hear the bike go by first hand :0( MY crew members said that it was much like a jet taking off a runway at full power.
By the end of the day we were all very pleased with the outcome. However I am sure that with a little modification that we can go faster. The afterburner was originally tuned to a low fuel burn rate which can be increased now that I know the afterburner duct can handle the heat. I can also streamline the bike with side panels and a faring of sorts to help the bike cut through the wind better. I am told that a faring alone could increase my speed by many miles an hour so we are not done by a long shot. If all goes well we should be back out at the lake bed in a few months to break this record. Boy this stuff is addicting!!!!!!
I would really like to thank my crew for all their help. I would not have been able to do any of this without the support of my good friends/family: (left to right) Evan, George, Sven, Erik, Andreas, (me), Kent and Mike. We will be back again for another go at it, I’m sure!!!
Thanks to all of the readers that have supported me throughout the years. It’s your positive comments that motivated me to build the bike and for that I am grateful :0) I will always remember this chapter in my life.
Thanks for reading my pages and be sure to check back again for the next installment of the GRV-2 jet bike project!!!!
