Yes, I’ve decided to name this new boat “Libby” after my mom who passed away almost 1 year ago. She always taught me that I could do anything I set my mind to, and I thought I would honor her by naming my new human powered record attempt boat after her.
And after this speed test on Okanagan lake in Kelowna, I realize that once again, this is going to be friggin close. So close that I know I cannot cut any corners. I must, must, must sweat every single smallest detail, or my speed just won’t be there to beat Carter’s 249 km record. I must believe in what my mom taught me – that I can do anything I set my mind to, because “belief” just might be the edge I need to get me to 249.
Specifically, I’m setting my mind to pedal Libby over 249 km in 24 hours. That’s a world record. YIKES. That’s 10.375 km/hour. 10 years ago when I set the initial WR, I did 245.16 km at an average pace of 10.21 kph. Now, with a body that is 10 years OLDER (I’m 56 now), on a boat that is *marginally* faster, I must increase my overall power output, or I will not be able to exceed 249 km in 24 hours. In 2014, Carter Johnson beat my 245 paddling his kayak 249 km for a new world record.
And when I say I have to sweat every detail, I mean EVERY DETAIL.
Here’s how the OK lake test went down:
Dad and I woke up just before dawn and drove the short half block to the public marina. I started to assemble Libby and realized that my Gorilla tape wasn’t sticking to the hull because it was so cold out! This was not good. My entire frame – that’s the seat and pedal assembly is temporarily taped to the deck so I can experiment with positioning the weight in the hull to set the right trim. Gorilla tape is strong stuff, and it sticks like crazy, so it’s more than required to hold the frame onto the deck… unless it’s zero degrees, in which case, the tape wont stick at all. We ended up having to load half of the hull into the back of the LR4 and crank up the heat for 20 minutes, tape, then flip the boat around and repeat for the stern half. Luckily that worked.
My first run out from the marina docks found sheet ice which I had to use my paddle to crack to get through to the open water on the other side. I was afraid of stories I’d heard about sharp ice slicing open thin carbon fiber hulls. So.. needless to say, I was very careful punching through the ice.
On the other side, I saw a speed of about 9.6 kph at exactly 100 watts of power. The water was perfectly calm – so a really good a valid test. I did notice that the floats were too low in the water, so I returned to the dock, and dad and I lifted the floats up by about 1/2 an inch.
The next trip out through the ice zone saw a speed of 10 kph at exactly 100 watts – so stabilizer floats that are too low cost about .5 kph. 10 kph at 100 watts and this was using my old CNC machined aluminum prop from the first world record. This time around, since I only have 1 aluminum prop remaining, and the guy who machined it isn’t doing that any more… I’ve had to switch to a similar plastic model aircraft prop.
My second speed test was using the model aircraft prop, and my speed DROPPED by .5 kph. Ugh!
That isn’t good news. The other problem with the old aluminum prop, is it is pitched for a different gear combination, and my cadence at 100 watts of power was 66 rpm. I’m supposed to be in the upper 80’s. that means that I’m going to have to re-design my gears by swapping out my large chain ring for a smaller one, or swapping out the smaller gear box gear for a larger one. Both solutions are a bit of a pain because the entire boat and frame and drive was designed with the current gear configuration. And, I have a custom made ($$) carbon fiber chain ring on order from the UK. I’ll be dammed if I have to give that baby up. But, I might have to.
I was a bit disappointed with the 10 kph speed @ 100 watts of power. I was hoping for something around 11 kph, not 10 kph. At 11 kph, I *should* have enough speed to maintain my power for 24 hours, and break 249 km. But not at 10. No way. Not at 56 years old anyhow…
Here is how that works out:
To measure my power output, I’m using PowerTap PowerPedals which are pedals that transmit my “pedaling force (power)” to a meter. I can focus on pushing out an exact amount of power in watts, then watch the GPS and record my speed. Then, I turn the boat around, and repeat the test going the opposite direction to negate any wind advantage. And then average the 2 readings.
So how do I know what my maximum average watts I am capable of putting out over a 24 hour period? Well, I have done many 24 hour races in the past, and I have some power data from those events. But, I’m now in a body that is 56 years old, and it’s slowing down. So, what I’m doing is estimating my “all day” power by taking my “functional threshold power” and taking 55% of that. “FTP” is the maximum average power I can hold for exactly 1 hour. There is a general formula that converts that FTP power to an equivalent average watts that one could sustain indefinitely – or at least over a 24 hour period. And that is 55% of FTP.
- My FTP = 210 watts
- 56% of 210 watts = 117 watts
- current speed @ 117 watts = 10.3 kph
- estimated 24 distance = 10.3 * 24 = 247 km (2 km SHORT of Carters record)
If you are a bike guy, you are probably wondering why my FTP sucks. Back in my prime – like 10 years ago when I set the record and when I qualified for Ironman Hawaii, my FTP on my tri bike was around 300 watts. This is a HUGE decrease in 10 years. But… it is what it is. And it’s not from a lack of training either. I’ve been training like crazy for months now. I think it may have something to do with the low recumbent position, my indoor mag trainer, and my 56 years of age. On a road bike, outside, it would probably be 250+.
So.. there is some hope that I should be able to do a bit better than 117 watts over 24 hours. Also, remember that I am talking about AVERAGE power over 24 hours, and that INCLUDES stopping for a few seconds to urinate, that includes all the short pauses to eat and drink, and change into warmer clothes, etc. If you have trained with power, you know exactly what I’m talking about. When you stop pedaling – even briefly, and even when you are “coasting”, you can actually watch your average power number start to FALL.
So.. what I’m saying is that 117 watts average over 24 hours is NOT as easy as it sounds. However, that said, if I can manage an average of, say around 125 over 24 hours, then my speed just might be high enough to get close to the record. But, I cannot rely on that. I need to try to get Libby set up such that she gives me at least 10.5 kph on 117 watts.
OK, so where is this speed going to come from?
DETAIL SWEATING SPEED GAINS:
- Change my hang-off-the-back kayak rudder for an under-the-hull rudder = .05 kph
- Find GUARANTEED calm water for 24 hours = .2 kph (compared to my last record on Whitefish Lake which was calm 1/2 of the time, and somewhat wavy the other half)
- Lose 7 pounds of “winter fat”, + 5 pounds of additional clothing I wore for the OK lake test = .05 kph
- Find a very LONG, WIDE body of water to reduce the turn radius = .05 kph
- Record attempt in warmer water = .02 kph
CURRENT SPEED @ 117 WATTS = 10.3 kph
CURRENT DISTANCE IN 24 HOURS = 247.2 km
TOTAL SPEED GAIN FROM DETAIL SWEATING = .37 kph
NEW PROJECTED SPEED = 10.67 kph
NEW PROJECTED DISTANCE IN 24 HOURS = 256 km
additionally, here is more work that needs to be done:
- Test the aircraft prop by trimming 30 mm off the tips, and adding a prop cone fairing (this *may* end up being as efficient as the aluminum prop, but I’m doubtful).
- Add friction to the gear box movable bracket (oil dripping from gear box was lubricating my bracket and my gear box was moving into the chain causing chain to derail).
- Possibly separate the pedal unit from the seat which will allow me to position the seat to account for different pedal thicknesses / seat cushions.
So there you go! I have a LOT of work to do. I just wish the lakes would start thawing here… We leave for a month-long hiking trip in Spain at the end of April, so time is running out. I have a record attempt tentatively planned for mid July.