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RocketFish : Nitro Harley Top Fuel/Nitro Funny Bike Transition

So You Want To Ride Top Fuel/Nitro Funny Bike?
by Dennis M. Fisher

RocketFish Nitro Harley Top Fuel/Nitro Funny Bike Transition

Talk about a wild year! A couple of years ago I wrote an article about my experience riding a Pro Fuel Nitro Harley. (CLICK HERE TO READ)  For those of you that recall that article, there are very few similarities between the Nitro Funny Bike and the Pro Fuel, and the differences are significant. The NFB is a much heavier bike, maybe 100 lbs or so. The astute observer will note there’s no dump can, and an extra velocity stack – one on each side of the motor. The reason for the extra velocity stack is because this motor is equipped with fuel injection – one throttle body for each cylinder. A few other VISIBLE differences – bigger rear tire, bigger chain, and oh – there’s that square bundle of laundry hanging on the wheelie bar, also known as a parachute. Since these beasts frequently play on the other side of 200 MPH, the rules require a parachute to aid in bringing the rocket to a halt.

What’s unseen is even more mind-boggling. Programmable ignition and timing, timers and valves to control fuel pressure and mapping, clutch engagement, a transponder to trigger ‘chute deployment, and many more data capture sensors.

Stepping up to the NFB from Pro Fuel was an eye-opener in increased complexity. Whereas the Pro Fueler was carbureted and had basic timers for lean-outs and limited ignition timing, the TF/NFB increases its sophistication and complexity by orders of magnitude – we have many more timer channels to be concerned with. Fuel pressure and timing mapping. Clutch management. Rev limiter (if you get there you’ve got other problems). Oh – don’t forget the parachute – and the red button that launches the laundry. I said many times early in the season if I knew ahead of time how much more complex the systems were on this bike, I may not have pulled the trigger. One thing stays the same though – grinding clutches is the same, and it still sucks!

There’s another thing that stays the same – the crucial importance of the crew. Early on in my racing career, my mentor Rickey Gadson (all this racing stuff started after attending Rickey Gadson’s Drag Racing School) hammered home the most important point – to succeed, having a capable and committed crew was an absolute, non-negotiable requirement. And after several iterations, I’ve found it. Steve Vickers of Hawaya Racing (who interestingly enough was involved in building this bike in 2011) is our Championship Crew Chief. Rick “Griz” Smoot of Smoot Construction is our “Chief Wrench” and renowned culinary expert. Rick’s partner, Kristi Bates is our Safety Officer and clutch prep/QC assistant. Kristi keeps us all safe and nourished. Being a long-time healthcare professional, she is invaluable to the team. This crew keeps me safe and is an enormous boost in confidence when throwing a leg over this bike.

The process of starting the bike is similar to Pro Fuel, but there are differences in systems. After a year of observing the process, I’m still not comfortable with trying to fire this bike without one or both of my crew present. One mistake and a bomb with no fuse goes off.

The process goes like this:

1) Bike on the starter stand
2) Starter cart shaft in motor
3) Ignition on
4) Engage starter cart
5) Spray gas/alcohol mix from SureShot cans in each throttle body
6) Turn on fuel
7) Disengage starter cart
8) Adjust injector air bleeds to equalize cylinder temps

Once fired and stabilized, we roll to the water box. Griz stops me at the leading edge of the water and wipes the front tire and we light it up, holding revs 4000 or so. Don’t hit the limiter, because if you do, things get real quiet and real embarrassing! Ease out of the water, and head to Chief Vickers whose foot is right where he wants the bike lined up. Griz is behind assisting in getting me lined up straight. Once that’s accomplished, Griz is tasked with the impossible – getting the ‘chute safety pulled from a moving target that is shaking violently while nitro fumes are making it impossible to see or breathe!

One thing I’ve noticed in all the video and photos of us staging and launching – as soon as they’re able, everyone – Griz, Kristi, Steve, others in close proximity – all have fingers in their ears – and for good reason. There is no sound like it, and if you don’t cover your ears, it hurts!

Comparing the ride of a NFB to a Pro Fueler is interesting. The front half is actually similar to the Pro Fuel ride – at least it was this year, but this was a “dial-it-in” year. Our 60’ times were similar to the PF, but we should be closer to 1.10 than 1.20. We’ll get there.

Where things get interesting is at the eighth. The Pro Fueler would lay over about that point – the front wheel would come down quickly and if the wheel wasn’t 100% straight, you get that fleeting wash-out/face plant sensation that comes and goes as long as you stay in the throttle. With the NFB, the eighth is where it comes to life. The pull is stronger, you’re still on the bar, the front wheel is in the air and the ride is getting crazy. Wind, buffeting, vibration fight to drive you off your target. While all this is going on, paying attention to the seat of your pants for tire shake/spin is crucial. These bikes have the ability to blow the tire away anywhere on the track.

On a good pass, the front wheel eases down around 1,000’. Many times you don’t even feel the touchdown. Spectators understand the higher speeds when they see the puff of smoke from the wheel touching down – not unlike an airliner touching down!

With the increased speeds it’s critical to tuck and get as small as possible – and keep a firm grip on the bars. Knowing the track and where the bumps are – and how to avoid them is huge. Once through the traps it’s time to get the rocket hauled down. First order of business is off the throttle, flip the fuel shut-off switch and get on the rear brake to settle the beast. Then punch the ‘chute button on the left bar. By then, you’ve slowed enough to start getting on the front brake, but not too much! Squeezing both brakes gets the bike slowing down enough to plan your exit from the track. Not as important for the Pro Fuelers or gas bikes, but our Top Fuel/NFB’s must make the planned exit for a post-run ritual unique to these bikes.

Every TF/NFB crew positions buckets of water or garden sprayers full of water to cool the clutch basket. These bikes create so much heat in a pass the basket must be cooled as soon as possible, otherwise the clutch can melt the carbon Kevlar belt – and at $500 each, you learn quickly the importance of cooling the clutch as soon as you turn off the track. The challenge is getting the bike off the track, making sure the ‘chute is clear of the track and getting water on the clutch while waiting on your crew to get there to take over the post-pass tasks. Most times you don’t even have time to get your gloves and helmet off until after the crew arrives, then you can start shedding race gear to cool yourself.

Once the bike is secured, you start the tow back to the pits to go to work on turning the bike around for the next pass. The tow back can be physically demanding and is a skill in and of itself. The tow strap wraps around the left grip. When the pit bike takes off it wants to pull the bars full right, so you’re using all the upper body strength you can to keep it straight while shifting your weight to keep the bike behind the pit bike. Once up to speed, you can relax a bit. Negotiating traffic and turns adds to the stress level, but once back at your pit it’s time to get to work.

The first order of business is “blowing out” the motor to make sure there’s no nitro in the cylinders. Then draining oil, changing plugs, reading the data, making any tune-up adjustments, refueling, adding oil and going over the bike front to back. One critical new skill I had to learn – and a major difference between TF/NFB – how to pack and load a parachute! Now that’s fun!

There is one point I have to emphasize – none of this would be possible without this incredible crew. We are thrilled to bring Steve Vickers his first championship as a Crew Chief, and it was overwhelmingly gratifying to win the 2017 NFB Championship with the support of Griz and Kristi in their first year of nitro racing. Another interesting point is both Griz and I started our racing careers on Harley Davidson VROD Destroyers – the purpose-built drag bike Harley made in 2006 to spark grassroots interest in drag racing. Looks to me like it worked!

When nitromethane is good, it’ll give you the ride of your life!


When nitromethane is BAD, it’ll give you a ride you’ll never forget!

See you in 2018!

Dennis M. Fisher
Owner & Pilot
RocketFish Nitro Harley

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