Friday, April 02, 2021

Inside Ronan McLaughlin’s Everesting world record bike

 How McLaughlin changed his pedaling position to get lower, and how he heavily considered aerodynamics for the descending portion of his record-setting effort.

The goal was a conundrum: ultra light and ultra aero.



Ronan McLaughlin, a tech writer for CyclingTips, set an Everesting world record of 6:40:54 on March 29 on a 5.55kg (12.24lb) bike that he constructed over many months, carefully weighing the benefits and drawbacks of each piece, both literally and figuratively, and even changing his pedaling position to fit onto a smaller frame and reduce his frontal profile.

“It’s often overlooked in Everesting, but half the event is downhill,” McLaughlin said. “When you are descending, it doesn’t count towards your elevation, but it does count towards your time. So I was looking to get downhill as fast as I could.”

To maximize the efficiency up and down, McLaughlin selected Mamore Gap in his native Ireland, a dead-straight stretch of road on a hill that averages 14 percent.

For the bike, McLaughlin selected a Giant TCR Advanced SL 2021 frameset, and then went to work on modifications — beginning with himself. 



“I spent the spent the winter on Speedplay [pedals], getting the cleats all the way back, to shrink myself down, and get onto a Medium frame instead of my normal Medium/Large,” said McLaughlin, explaining that the goal was to reduce the front profile of bike and rider, and thus the overall drag. “My saddle height went down by just under a centimeter. A small adjustment at the cleats resulted in a big difference at the saddle, and I was able to lower the bar slightly, too.”

In what is almost certainly a first for an Everesting world record, McLaughlin used a fairing on the front of his bike from TriRig that he modified to fit on his Giant. He connected it to a Deda Tribar aero basebar and a Cane Creek ee brake caliper.

“I hoped to use a TriRig Alpha base bar and brake calipers that the fairing essentially snaps onto, but with the Giant Overdrive steerer, that integrated setup wouldn’t fit. I had no option but to get the hacksaw and tape out and make it fit,” he said.



For wheels, McLaughlin initially had the choice between Cadex 40s and AX-Lightness Ultra 38T carbon tubulars, but once a Cadex spoke was damaged in shipping, his decision was made for him. For tires, he went with Vittoria Corsa Speed 2.0 tubulars, which are thin, light, and fast. He punctured the rear 25mm tire midway through his effort — “I locked up the back wheel a couple of times at the turnaround, and in fairness these tires are not designed for country backroads” — and switched to a backup bike for a couple of laps while his crew of friends and family changed the wheel.

He ran tire pressures of 74psi front and 76psi rear.

To gauge his effort, McLaughlin worked primarily with a time target, using power and heart rate as limiters. Shooting for a finishing time of six hours and 50 minutes meant targeting 5:22 laps. If his power exceeded 400w or his heart rate 172bpm, he knew to back it off.

Incredibly, his normalized power for the day — including two laps with no power meter and two laps at the end when he backed off on the effort — was 312 watts. And yes, that includes the descending when his power was zero after the initial acceleration.

“People have calculated that I did 76 hill repeats at 350 watts,” said McLaughlin.

McLaughlin spent substantial time on his drivetrain, selecting a single 44t Wolf Teeth chain ring and constructing a 7-speed cassette using Shimano XTR and Shimano Dura-Ace components.

“Previously I had a low gear of 39-32,” he said. “This time I wanted a bigger ring and sprockets for increased drivetrain efficiency through less chain articulation. Also, if I wanted to Everest faster, I was going to have to push a bigger gear.”



So, he aligned a 35t cog dead center on the cassette body, with a 40t cog as a bailout. His smallest usable cog was a 17t. An 11t cog was used along with spacers to hold it all together, but he wasn’t able to shift into it.

CeramicSpeed provided both equipment and advice over a few months of preparation. In addition to the oversized derailleur pulley wheels and UFO-coated chain, CeramicSpeed also gave him a bottom bracket and hubs with ceramic UFO-coated bearings. Instead of using grease inside the bottom bracket, McLaughin used oil.

“It was a one-day job, having the bearings running in oil rather than in grease, but it was faster,” he said.

Lastly, McLaughlin also used two non-traditional monitoring systems in the form of a Core body temperature monitor and a Supersapiens glucose monitor.

“Those were more for post-ride analysis than real-time usage, but I did use the Core monitor in the lead-in to the effort,” he said of the small monitor that clips onto a heart-rate strap.

The team at Core has developed a heat-ramp test to determine a rider’s ideal heat training zone, and McLaughlin said that while he found training in that zone to be effective in raising his blood plasma volume, the heat-rate test itself was no fun at all.


“I would rather Everest again than do a heat-ramp test again,” he said.



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