Today, Obree has added around 300 grammes of weight to the front wheel in order to stabilise the bike and the steering, as well as changing the primary drive sprocket from a 17-tooth to 12-tooth. This increases the gear to approximately 290 inches, roughly the same as for his initial runway tests.
**EDITOR’S UPDATE – 13/09/2013
The latest update from Battle Mountain since this feature was written is that Obree set a new World Record for the Human-Powered Two Wheel Prone Recumbent with a 52.9 mph run. According to Rick Robson and Obree’s team in the chase car, the car speedo was up between 55 – 60 mph after three miles, then the speedo dropped to 50mph before the timed 200 speed trap, with the Flying Scotsman coming in at 52.9 mph.
It’s now clear that an overall Human-Powered World Record attempt to break the current 83 mph target isn’t possible, however the 67.4 mph British record set by Rob English in 2002 is still achievable. He has one last day to attempt the record before the end of the competition.
Obree told Rick Robson, our photographer on the ground in Battle Mountain: “I went too early building the speed, then I just tried to hang on but the speed dropped. But hey-ho, no one’s died, the fish and chip papers will still be blowing around Saltcoats, the clouds rolling in over Arran”
“Well, Homer Simpson said the key to happiness was to lower your expectations, and with the World Record a long way off, on a well-timed effort I could get to the British record.”
Read the interview below where Obree talks about what he’s learnt on Battle Mountain. Humans Invent will have the final word with Obree over the weekend, once the competition has officially closed.
We caught up with Obree to talk about his attempt thus far and gain a greater understanding for the engineering journey he is on at Battle Mountain.
I am just about to change the gearing on the Beastie back up to the 300 inch gear. Well, in theory you think a good cadence is better. But in reality, that isn’t true. I was talking to the Cygnus Beta boys, who are great. I have learnt that this sport is all about collaboration. I’m used to such competitive environments but this is more of a rally mentality. It’s a great vibe. They were looking at my bike and they were saying it was going sideways all the time because of the flat surface.
There is too much flat surface compared the natural movement in the atmosphere. They were explaining that control is more important than power and that is why they said I need to put the bigger gear on the bike. So they reckon the gear will allow me more control, and, using the same pedalling rate mean I can create a higher velocity.
Intuitively, theory maybe right but in the real world it can be wrong!
Those boys have been great at advising me how to ride the 5 mile course. They explained how to utilise a slow-energy build up and where on the course the undulations are, and therefore when and where to plan the best area of attack for the best finish and result for the record.
So, you are learning that knowledge of the course is key?
There is a slight downhill part where you can get an extra 5 mph or so. Maybe more. Normally at the last minute I will give it a real punt, really go for it and lose it. That would normally mean in a flat race, that would be the last four laps and I wouldn’t let anybody pass me. So, that would be a huge power output.
But when I am doing that now the bike is snaking about because of an imbalance of force and the flat, true surface. So, really it has been hard to control the bike and keep it in a straight line. Which means you are picking up more frontal area and therefore ironically, going slower for your effort. It really has been a huge learning curve with the amount of amazing knowledge that they have here.
It’s amazing thing if you think about it. Intuitively theory maybe right, but in the real world it can be wrong. You have to respect this. Some of these guys have been here coming back for 5 years, using trial and error and working things out each year, gaining knowledge at every attempt they make. I’m learning, what intuitively seems right and what in the real world seems right is a different balance. A guy was explaining it to me, and he was an aeronautical engineer. He was saying even the main theories of aeronautics, when you get them in the real world you have to make alterations. And that is from standard aeronautical theory. These guys have said they have learned to make changed from standard aeronautical theory to get their bike to go faster. It really is quite amazing. I wouldn’t have known that without coming out and testing the bike.
To be honest I find it just incredible. The whole thing is incredible. The body of knowledge here is the equivalent to a university of its own. The guy I was talking to, Thomas from Cygnus Beta, has influenced the design and thinking behind a global car manufacturer. That genuinely is incredible! They have changed the design programme. What was standard modelling on aerodynamics was sub-standard compared to what their knowledge is. In the real world, they have altered a company’s multi-million pound design programme! This is purely out of their amateur enthusiasm and their body of knowledge going beyond the automotive industry.
And these are the people I am competing against! I think ‘oh my goodness’! What I have realised is actually how little I know. You can only know so much from first principles and what you think is right. When I built the Beastie I thought, ‘that’s a great bit of engineering, it must be quick.’ But in the real world there are other issues, and these guys have garnered 5 years of knowledge some of them, so it is a bit of a head start. If I’m being honest I could have done with more testing, but really you don’t get to the bottom line until you speak to these guys and actually come out here. They are proper enthusiasts, and they really want to help you get the best out of your machine. It’s more of a club, a collaborative approach to engineering! And you cannot access that body of knowledge anywhere else in the world apart from here.
My plan of action is change the gearing today, which is quite a long job. I need to take the entire bike out and put more weight on the front wheel. Normally in the real world of cycling, you want the front wheel to be as light as possible, in terms of steering and response time, but out here in the quantum world of cycling, it is really different. What is the norm in the cycling world, out here is completely different.
They reckon you want to get as much weight as you can on the front wheel for stability reasons. Which is counter-intuitive to normal cycling, because you think ‘I cannot steer as quick.’ So we are going to put some lead weights on the wheel today. With the bike out of the shell I will work on the gearing and front wheel, put it back together and have a run this evening.
The body of knowledge here is the equivalent to a university of its own.
In the morning run, there is 9 mile / hour headwind. There is one point in the evening when the sun goes down and the wind drops, it is almost predictable. Unfortunately,because of my qualifying speed, which is quite poor and I wasn’t happy with it, I am in the earlier group, so I have to take what I can get.
I can’t keep going every day, with tired legs. At some point you need to take your learnings and say ‘right, that’s the run, this is the ride, I am going to have a go! Let’s do it!’If I can use the 5 mile run in the morning on Thursday and Friday, I think that will be it. One of those. But to be honest, because I cannot change the shape of the shell and the fact that I have stability issues, and I cannot do a rebuild here, it means I have to make the best of what I have. Fundamentally, I need humility, I have done the best I can in terms of relying on first principles, but in reality, it is very mediocre in terms of the years of experience that these other guys have brought to the table.