I’ve ridden a Specialized Shiv since 2012. Over this time I’ve gradually tweaked my position and setup, but eventually ended up unable to get low enough. I was as aero as I was going to get on it, short of resorting to workarounds such as super thin dust cap + and special “below extension pad mounts”. So I decided to start my search for a new bike, with optimal position being the starting point. I began with a clean slate, visiting Jim @ Ero several months ago for a fit on his Retul fit bike. I chose Jim because he understands aerodynamics, power, comfort, and the combination of all these things working together. I’ve been to too many fitters who hear that I’m racing Ironman and immediately set me up for a more relaxed, “comfortable” position. Personally I place the premium on aero, as long as it doesn’t create too much discomfort.
Jim started by getting me into a super aero position, and then tweaking my position until maximum power vs RPE was reached. What was pretty interesting, is that I was unable to see my power output, Jim just told me to ride at the same perceived effort. With just a few small tweaks, I was putting out about 40 watts more at the same RPE than I was in both a “higher” and “lower” stack setup. The pic below shows my new fit vs the position on my shiv. The red line is the same in both pics to show you how it’s different. Basically it’s longer and lower.
So next was the bike choice. We narrowed it down to a few options: Trek SC, Felt DA, Cervelo P5 and Dimond.
I really like the Trek SC because it’s super aero, has a great design, excellent storage options, and nice clean solutions for cable routing etc. I also really like the P5 – what a fine machine and superb quality. As for Felt, I would have considered the IA but it wouldn’t fit me, and the DA just seemed like I’d be choosing an older design from them, and tweaking the fit would have been a bit harder than the Trek and P5.
Now, the Dimond really stood out for me because of it’s unique design, which I feel could *possibly* be more aero than the others, and *possibly* offering some level of energy saving due to the beam design (I don’t have data on the energy saving, but I’ve spoken to several people who have raced on beam bikes and all of them talk about better running off the bike). I also liked the fact that they are hand made here in the USA and I was super impressed with the personal attention I received from the guys at Ruster Sports.
So, with my decision made, I reached out to the guys at Dimond who accepted me to race on team Dimond for the remainder of this season. Next up was component choice. This is what I went with:
– Shimano di2 groupset
– Zipp vuka stealth bars with zipp BTA mount
– tririg omega brakes (really love the aeroness of the center pull)
– power2max type s power meter with rotor cranks and praxis chainrings
– saddle: originally planned on using my Sitero saddle, but the rails are oval and don’t fit the clamp. At the moment I’ve got my ISM TT but I’ve got a Dash TT.9 on order. I considered the Fizik Tritone but I don’t think having 2 x bottles on the side is as aero as a single bottle (and I don’t need 2)
– wheels: I have existing zipp wheels. Most races will be disc + 808. Kona will be 808 + 404
I’ve ridden it a few times outside. I love the position (feels super fast), and the bike is very stable in cross winds. I was riding in heavy wind with an 808 in front and it felt fine, not as sketchy as I’ve felt in the past. Possibly due to the “open” rear end of the bike. Speed-wise it seems pretty fast. On some of my local loops I’ve got times about 2 mins faster (48 min vs 50 min) at the same power output as the Shiv. I wouldn’t read too much into that though, since
My first race on it will be The Big Kahuna in Santa Cruz (half iron) and then Kona (808,404) followed by IMAZ (disc, 808). I really look forward to finding out how it performs under pressure!
Here are some pics so far (took them with phone). Still need to do some cable cleanup, especially that rear brake cable coming up in the front.