If you go to an event and observe the riders on time trial machines you will see a wide range of front end positions. Getting the most efficient position for both aero performance and power production is the Holy Grail. In this post I attempt to give some structure to the process of finding that position ….
Test session at Newport Velodrome 28th February 2018
I book a three hour slot at Newport Velodrome once or twice a year, and use the data to validate my “open field” test results and to refine options. In this session I was benchmarking a 54 P3 with a new configuration of bars and wheels. In parallel I tested some shoe and helmet combinations.
Zwift Workout files
If you are doing high end intervals ERG mode isn’t always what you need. There is a way to disable ERG mode in Zwift without having Zwift change the turbo resistance if the terrain changes e.g. the incline changes or you ride over a bit of “feature landscape” like a wooden bridge section. It does mean manually creating a .zwo …
Instrumentation to help with the interpretation of your results
Those that have read the Aerolab User Guide will have noted the requirements to set the air density, or Rho, as it is termed, and also set the Coefficient of Rolling Resistance, or Crr.
Aerolab and Power Meter Confidence Limits
I have been asked the question, how accurate are the results from Aerolab? It’s not a straight forward answer as there are margins of error in multiple aspects of the process.
Cross-calibrating test venues
I find it quite useful to have some idea of what my wind tunnel numbers might be. One way to do this is to cross-calibrate test venues with a trace back to a wind tunnel result.
Wheel and tyre comparisons
Some pretty basic wheel and tyre comparisons – I’m limited by the availability of wheels and testing equipment, but …..
Drive Train Options
I guess we’ve all heard of drive train losses and drive train efficiency. There was a blog post on “keeping it clean” 13th October 2016. I’ve talked to a few people since then, and picked up some interesting tips.
Cervelo P3 TriRig upgrade………….
Upgrade of a Cervelo P3 with TriRig Alpha X base bar and riser kit, with the extension clamp tilt option, fully installed with Di2 extension shifters and Di2 brake lever shifters. No more difficult to install than any other aero base bar I’ve experienced.
Newport Velodrome Report
I book a three hour slot at Newport Velodrome twice a year. I use these to validate my “open field” test results and to refine options. I book November and February as a rule, something to do with the weather. It gets a bit too cold to test in a skin suit once the clocks go back.