Bonneville Land Speed Records by Alastair Gibson

"The 2026 Bonneville Motorcycle Speed Trials, also known as the AMA Land Speed Grand Championship and FIM Land Speed World Records event, are scheduled from August 23rd to August 27th at the Bonneville Salt Flats, Utah. This annual event attracts motorcyclists aiming to set national and world speed records, featuring various classes, including electric motorcycles. It is sanctioned by both the American Motorcyclist Association and the Fédération Internationale de Motocyclisme." www.bonnevillemst.com

This year he will be attempting to break the Land Speed Record in the 500 M-VBF (Modified Frame Vintage Engine on Blown Fuel) class.

Alastair's father- Al Senior did some land speed racing in South Africa in the early 1940s on a similar bike so he hopes to replicate and honour his father's ambition of getting up to speeds of over 100mph on a 1938 motorcycle-which is no easy feat due to the altitude and the heat of the Bonneville Salt Flats!

Follow Alastair's progress here;

The Road to Bonneville

The 2026 Bonneville AMA Grand Champion Speed Trials have started off in earnest. 

The three of us met at Salt Lake City Airport on Thursday and started getting ready to make our way to Wendover on the Utah / Nevada border. This is the closest town to the Salt Flats. We picked up the rental truck, collected the motorcycle, and did our normal supply run at The Home Depot - tent, chairs, bolts, etc. 

Because we had time to spare, we took a visit to the Antelope Island State Park and were lucky to see some wild American bison up close. We then set out to Wendover, arriving Friday afternoon. 

Today we went onto the salt for the first time and were impressed with the condition of the race track. After setting up camp, we prepared the bike for scruitineering, which passed with few small adjustments. 

On our way home we had an authentic Mexican meal and will attend the drivers briefing tomorrow at 8am. Our last two team members, Graeme and Simon will meet us on the salt tomorrow.

Our first run should be completed mid-morning, and we will provide another update tomorrow evening.

Taking on The Salt

Day 2 on the salt, and the first day of running. The whole team is together now, consisting of myself, my son William, my friends Tom, Graeme, and Simon. William, Tom and Graeme helped me during my successful 2024 record breaking.

This morning at 8am we had the riders briefing which dealt with all aspects of racing at Bonneville on the salt. We decided amongst ourselves to approach the first run very conservatively. So we retarded the timing to 35 degrees before top dead centre and one jet richer in the carburettor.

By the time we were in line, it was extremely hot, around 98 F (36 C) - a perfect day with no wind at all. The run was disappointing but safe and a scaredy cat value of 2/10. The biggest problem we had was the lack of boost from the supercharger. This could be due to various factors which we are looking at this evening.

We also did a second run with the exact same settings of my previous test run at Alvington. We achieved 96 mph in the measured mile, a little bit better and more revs, but still no real boost to talk of. Tomorrow morning we will test some ideas to improve boost.

One shining light is that the surface of the salt is fantastic and we are racing on the Hydromax circuit. Hope you enjoy the images and video of what it’s like to race the Bonneville mile.

Making Progress

Day 3 on the salt. Spent the morning getting the bike ready for a mid-day run, installed a larger carburetor and adjusted supercharged pulley length, retarded timing to 35 degrees before top dead centre, and after a long discussion kept the jets the same. We achieved 98.639 mph on the run. Boost pressure at 6 psi now, and still on the rich side of the fuel mixture.

The afternoon got very stormy so we missed the run but going out to the salt at 6am tomorrow morning to try again in hopefully cold, dense air. 

Some stats from the morning run:

    ⁃    Temperature was 89.7 F

    ⁃    Humidity was 29%

    ⁃    Density altitude was 7,109 ft

Thanks for all the encouraging comments, will send another update tomorrow.

The Big Breakthrough

Day 4 on the salt. Today was our big breakthrough - we have unlocked the key for the superchargers performance. We arrived very early in the dark, unpacked the bike, and got ready to go down pre-stage where we were lucky enough to be bumped up to start at Mile 1. This helped us get enough speed on the supercharger for it to start working properly.

The temperature reading was 72.7 F and the density altitude was 5.928 ft. We had a great run with this two-mile run up and achieved a speed of 102.7 mph, which gave us the opportunity to do a return run and set the record.

We went to the impound for them to seal the engine and then set off to Mile 5 to do our return run. Unfortunately we did not complete this run as we had a problem with the carburetor and the engine cut out just before entering the measured mile. We got towed back to our pit and rectified the problem, then set off again to start the whole process again.

During this time the track got hotter and we did our third run at 92.4 F at a density altitude of 7,149 ft. This was the best run of the day, and we managed a speed of 104.3 mph which allowed us to go back to Mile 5 and do a return run at 100.7 mph.

So the average of the two runs was 102.6 mph, which is now the record for 500 cc Modified Frame Vintage Engine Supercharged on fuel, held by Alastair Gibson. 

Tomorrow we are going to have an early start and be on the salt by 6am. We have now changed class and will do the same as above with gasoline instead of fuel.

Hopefully, provided everything goes well, this will give us our second record. We feel very relieved and everyone is looking forward to the next three records we would like to attempt.

A Record Breaking Day on The Salt

Day 5 on the salt. Most amazing day for the Brooklands to Bonneville team. 

We were on the salt by 6am, and with the information that the supercharger works a lot better when the conditions are cool, we set a record at 105.29 mph in the 500 cc Modified Frame Vintage Engine Supercharged on gasoline class, at an altitude density of 6,000 ft. We were very surprised how much power we had for this record.

We then decided to put our bespoke fairing on the bike to make it a modified partial streamline, and then we did one run to see if the fairing was stable and didn’t cause any massive vibrations on the bike.

This run gave us 111.21 mph, the best we have seen since arriving on the salt. It was amazing to do this time because it was achieved at 96 F (35.55 C), the hottest time of day, and an altitude density of 7,200 ft. 

Having achieved this time, we sort of had to do a return run and achieved 106.01 mph which made us have a new record for 500 cc Modified Partial Streamlined Vintage Blown Gasoline at 108.61 mph.

We were absolutely delighted to achieve these two new records in one day. The motorcycle is performing brilliantly and it is a huge honor to the people who built it in 1938.

Tomorrow morning is our last morning and we want to try and do a run at 7am to try get the best weather conditions for our supercharger. If we get this record, we will have achieved our goal for the 2026 Bonneville Motorcycle Speed Trials.

Mission Accomplished

Day 6 on the salt. In order to fulfill my 2026 Bonneville plan, I had to achieve my last record this morning. 

After changing from gasoline to fuel overnight with the Modified Partial Streamline fairing, we got out to the salt at 6 am, and by 7:15 am we had our first run after being processed very quickly at Mile 1. We achieved 107.284 mph and qualified for a return run. However the engine was running very lean due to the supercharger doing its job and boosting at 7 psi. 

We returned to the impound and got a clearance to change jetting for the return run. On this run we achieved 108.434 mph which gave us our fourth and final record of 107.855 mph! The plan was achieved with great success and a lot of hard work by the team.

 

After the bike cooled down, we started dismantling the engine for the scrutineering checks, of which we passed without any problems and the four records were confirmed by the AMA. 

We then started the hard task of packing the bike into the flight case, loading it into the U-Haul trailer, and taking it to the jet blaster to clean the salt that had compounded on it. 

We have just returned from the awards party, and are completely knackered. Tomorrow we return to Salt Lake City to drop off the bike, U-Haul trailer and rental truck. Over the weekend we will share our full report of the experience. 

Thank you all for the positive comments and support that kept us going throughout the week, I have learnt a lot about supercharging a 500 cc pre-war BMW engine at altitude.

Full Report

I am now in Los Angeles with my son William and taking some well-deserved downtime after a successful albeit difficult week on the salt.

In summary we achieved four AMA records with my Blown/ Supercharged 1938 BMW R51/1;

- Record 1 — 500/M/VBF — 102.596 mph

- Record 2 — 500/M/VBG — 105.290 mph

- Record 3 — 500/MPS/VBG — 108.643 mph

- Record 4 — 500/MPS/VBF — 107.855 mph

 

To explain how to read the classes above,

* 500 = 500 cubic centimeters (cc), engine capacity

* M = Modified Frame

* PS = Partial Streamlined

* V = Vintage Engine, vintage for AMA and FIM (pre-1956)

* B = Blown / Supercharged

* F = Fuel (e.g. methanol, nitrous oxide, nitro methane, etc.)

* G = Gasoline, supplied by the meeting vendor, all gasoline records are on the same fuel (e.g. pump gas, E85, etc.)

We would like to thank everybody for reading our messages from each day on the salt. Your comments helped the team stay focused and motivated in the blistering heat.

I would like to personally thank my sponsors Simon from Brooklands Watch Company, Andy from Global Logistics Management Ltd., and Carbon Art 45. A huge thanks as well to my team William, Tom, Graeme, and Simon for sharing in the pain of the experience.

Stats of every day occurrences:

* Runs completed: 15

* Miles completed on the salt: 75 mi

* Number of hours waiting at the start line: 8 hours

* Hours a day spent in my leathers, in the sweltering, 100 F sun: 30

* Number of people commenting on the engineering of my bike: 20

* Amount of water consumed per person, per day: 2,800 mL

* Number of morning coffees from Starbucks: 28

* Callings for the cookie tray per day: 5

* ⁠Number of cats outside of Motel 6 room: 7

* Visits to the Honey Bucket: 22

* Average duration of breath held while visiting the Honey Bucket: 15 seconds

* Amount of time to walk around the paddocks and check out the other bikes: 0 hours, 0 minutes and 0 seconds

* Number of scaredy cat moments on the salt: 2

* Number of times reminded by my son to drive in the center of the lane: 35

* Number of salt bogey episodes per day: 3

* Number of times I got pulled off by Tom: 12 (leathers)

Hope everyone enjoyed it as much as we did, and hopefully we can go again.

 

Special thanks to our sponsors;

Luxury watch brand Brooklands Watch Company has kindly offered to sponsor Alastair on his latest land speed record endeavours.

"Founded in 2017 by aero-mechanical engineer Simon Jeffs, Brooklands Watch Company draws inspiration from the historic Brooklands circuit — the birthplace of British motorsport and the location where the world’s first motor racing chronograph was invented in 1907."

Alastair is proud to represent Brooklands Watches as an Ambassador, joining an exceptional group of British Speed Legends including Andy Wallace, Andy Green and Richard Noble.

We are incredibly grateful for their support and excited to have Brooklands Watch Company as part of this incredible journey.

www.brooklandswatches.com