In an earlier post, I mentioned that I was un-impressed with the SRAM Red Etap disc brakes on my 3T Strada project build. I decided to make the switch to Shimano Dura-Ace this winter. Shimano brakes offer better pad retraction, more modulation, and a firmer feel, and the Dura-Ace 9170 flat mount brakes didn’t disappoint. I also switched to a dura-ace crank (although the old Force 1x crank is completely compatible) to complete the groupset. For the Dura-Ace 1x conversion, I went with a 46t Wolftooth ring, and gold Wolftooth 6mm crank bolts to match a gold KMC chain. If you’re considering the Wofltooth for Dura-Ace 9100 series, their website indicates that you have to modify the chainring to fit the 9100 crank arm profile. Wolftooth appears to have fixed this, as my 46t chainring came appropriately shaped to fit the cranks.
The switch from a 30mm SRAM crank to a 24mm Shimano required a new BB. Once again, I went with a Wheels Manufacture “thread together” 386EVO BB…no more creaking press-fit BBs!
The idea with the Strada project was to build an aero bike using the controversial ‘marginal gains’ philosophy. The philosophy is often credited to Sir David Brailsford, the general manager of Team Sky (now Team Ineos). The idea is that if all the factors involved in racing bicycles were improved slightly, the resulting improvement would be significant. Team sky experimented with everything from bringing their own custom mattresses to hotels during the Tour de France, to food choices, sports psychology, bike technology, etc. With the Strada project build, I was most interested in the bike tech. For me, this means reducing wind resistance (drag), and the frictional losses in the various rotating components. For wind resistance, you can reduce drag with deep section wheels, aerodynamic tires, frames, and other components. But the reality is that the rider is responsible for most of the drag, so ensuring that your body positioning is optimized for aerodynamics (while still maintaining comfort) and your cycling clothing is form fitting, and not flapping in the wind will net you the biggest gains.
My Strada already had aero-optimized wheels and tires (more on that later), handlebar and stem. So, I slammed the stem to lower the front end (I was able to stay with the 120mm Enve stem at -7o, and still stay comfortable by bringing the seat forward 10mm).
Next was frictional losses. First, I installed a Ceramicspeed oversized pulley wheel system on the Dura-Ace 9100 rear derailleur (with gold pulleys of course!). According to Ceramicspeed, these OSPW systems save 2.4 Watts over a stock 11t Dura-Ace cage/pulleys. I gained another 4-6 Watts by meticulously removing the KMC factory chain lube, and applying the Ceramicspeed UFO drip chain lube. This chain lube is a dry lube, and is designed to decrease the friction in the chain as it articulates through the cassette, pulleys, and chainring. It’s expensive at $125/bottle, and it’s only good for about 10 applications (~max 2000 kms), but nobody said marginal gains was cheap!
What’s next? The only other way I can reasonably expect to save frictional watts is by changing out the wheel and bottom bracket bearings for low friction ceramic bearings. That’s another 5-7 Watts total savings, according to Ceramicspeed testing.
Finally, I want to address a new report on drivetrain friction. This report shows that a 1x drivetrain has higher frictional losses than a 2x, in almost every scenario! This is primarily due to the increased frictional losses caused by the chain articulation around the smaller cogs, especially the 10t cogs common on 1x systems. Frictional losses from chain articulation outweigh frictional losses from cross-chaining every time. The only issue I have with this test is the chainring size. They tested a 39/53 standard chainring, not a 34/50 compact chainring that is increasingly common on most recreational bikes. My previous road bike had 34/50 chainring with an 11-28 cassette. I believe that the 1x frictional losses are much closer to 2x for chainring/cog combinations that most recreational riders use, including myself. I would be very interested to see how the results differ with a compact chainring!
The final change I made to the Strada is swapping tires from Schwalbe Pro One to Mavic Yksion Pro UST. Both tires are marked as 28mm’s, however, the Mavics measure just under 30mm when mounted tubeless to the Enves (compared to just over 31.5mm for the Schwalbe). This results in another small decrease in drag. I’m still running approximately 62 psi for a smooth, comfortable ride.
Keep an eye out for future updates as I continue to search for marginal gains. And if you leave a question in the comments, the bike depot staff will try our best to answer it. Better yet, come on into the store and talk to somebody! Have a great riding season!
-Anonymous former Bike Depot Employee