Mad Max

Bonneville conjures up images of Mickey Thompson and Don Vesco and the vast and endless salt flats but it doesn't seem like it is "offroad." El Mirage and Muroc, that's dirt. Even with motorcycles going faster than 215 mph and cars going over 300 mph, its dirt, and that smacks of offroad. But when to look down the 5 mile course, and start the 2 YZ80s between your legs, you know you are in a offroad race and it sounds like your in the middle of a motocross track.

Feeling Small

The 53rd annual running of Speed Week was August 11-17, 2001. The entry count was approximately 346 with over 2000 runs on the 3 mile and 5 mile course. The weather was perfect even with occasional showers, which proved to give us a break from the hot sun. It rained one night on the salt, but by morning there was no trace of water on the courses. The salt was so hard, in fact, it reminded some of us of the old days.

Team McLeish Bros. Derek, Doug, Robert McLeish, Doug Plank

Team McLeish Bros has set 5 Bonneville records and 5 dry lakes records so how did we get here and what did we do? It started with my brother Doug stopping at Bonneville with his 4 daughters and telling me he always dreamed about running at the salt flats. This is where Hot Rodding started and where you see few "factory" teams, the last bastion of amateur racing on a worldwide scale.

Due to costs, new blood is coming to the sport from the motorcycle side, and hopefully with some changes in the committee, innovation also showing up in motorcycles. Many of the fast small displacement cars use motorcycle engines. Land Speed Racing has actually been repairing the salt flats for the last five years, so the BLM loves us.

Having raced every kind of off road motorcycle race in the 60s and 70s, we knew a little about getting hp out of small bore engines. I'm 54, and a little older now, but still like the riding my bikes in the dirt. Two years ago we pulled out of mothballs my old Yamaha HT1 Enduro, which I campaigned to many moto-cross wins in 1970 (even crazy enough to race it at the Carlsbad GP course, with 3 inches of travel) and set a Production 100cc record of 83 mph in the dirt at el Mirage.

Engines on Floor

So when it was time to get some modern engines we approached Yamaha. Here was our pitch. There are very few 175cc race bikes. Lot's of 125cc, 250cc, 500cc so why not mount two 83cc engines and have an ultra fast 175cc. A big plus was the YZ80 had been named Bike of the Year by Moto-Cross Action Magazine for 2000 and had won 10 or more National Championships the last few years so we knew they were fast and reliable.

RLV Pipes

After way too much waiting, we got the engines two weeks before Bonneville. Now its truly panic time. We had to engineer the mounts, expansion chamber, clutch, throttle cable, nitrous set up and transmission approach. With the engines on the ground we must have tried 5 different setups. Flywheels linked with Gilmer belts, side by side and coupled, cut the front engine trans off and drive both from the clutch side, etc. We finally came up with a trans coupling on both drive side sprockets. The good news was it meant we had two of everything and the bad news was we had to manage two of everything.

We got hooked up with the guys at RLV and that saved a tremendous amount of fabrication time and the pipes were so well engineered (and made tons of hp), we were able to snake them into the engine bay.

205mph Knobby - Jason McVicar

So why the wing....We started building a 175cc bike but when we submitted our crazy idea, the Tech Chairman thought we would have too much advantage and changed the rules before last years Bonneville meet, so we added a "sidecar." But most of the sidecars we seen were cobbled together piles of tubing, probably the dirtiest aerodynamic shape you could ever create. What if we made the sidecar a streamlined platform like a wing and what if we put it high it would clear ground effect and have very little drag. We now believe that in the ultra high horsepower classes a sidecar may help put the power down on the ground. We know one of the 200mph bikes front tire was clocked at 210mph while the back tire registered 260mph!

Measuring Tape

Winging It

With about ? hour of engine time, we headed of to Bonneville. We were confident in the frame package but not sure how the engines would operate. But going thru tech found a new interpretation of the rulebook meant our platform was now undersized.

Breakfast Table

The same platform built exactly to the rules and run 10 times previously thru tech was now an inch too short. So we borrowed some appropriately shaped aluminum and did a field fabrication job that cost us no drag and made for a wonderful picnic table.

Launch Mark

Our first run let us know that one of our design decisions was faulty. We had linked both engines to shift at the same time, which was great on launching the bike, but caused problems when engine number 1 was in 5th and engine number 2 was in 6th.

Transmission Setup

Time for field fabrication number 2. We split the shifter and I shifted 12 times on every run. Think, "shift on the Japanese side, now the English side, now the Japanese side," you get the picture.

Tiny Sprocket

Nitrous

The bike ran 114mph and backed it up with an 113mph in the fuel class. But it was not really fuel because we did not have time to hook up the 30mm carbs and nitrous. So we'll be changing the gearing, and we'll be out at el Mirage in the dirt trying to be the fastest 175cc bike ever, and wait till we get those 2002 YZ80s.

Derek McLeish

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