It doesn't look like the editing worked well for my last post (any multiple spaces were shrinked to a single space). Another attempt at the table is below. With the wind the Guru was 1.0% slower to 1.8% faster. Against the wind the Guru was 3.5% to 5.6% slower.

Guru Tests
Dist Pwr Cd Spd Time
2.06 219 70 15.3 8:03
2.03 219 77 23.2 5:15
2.05 279 71 18.2 6:45
2.02 279 74 25.6 4:45
1.76 249 81 17.7 5:57
1.75 250 75 24.1 4:21



Cervelo Tests
Dist Pwr Cd Spd Time Diff
2.04 218 71 16.1 7:38 5.2%
2.03 220 74 23.4 5:12 1.0%
2.05 279 68 18.9 6:31 3.5%
2.03 279 75 25.2 4:50 -1.8% (Guru faster)
1.76 249 73 18.8 5:37 5.6%
1.75 249 72 23.7 4:26 -1.9% (Guru faster)

Cool test idea actually. I would have to agree that the bike fits the rider, and the Cervelo may be a better fit for you that the Guru. Having said that- 85% of the drag is coming form the ride and a proper fit will yield a more aerodynamic result than the frame, no? But will no static air (like in a tunnel) I would venture to say that any improvement you see is likely based on your fit on your Cervelo. It also depends what you are looking for out of the frame. Personally I want a standard head tube bike (as my cannondale RS Slice) was a mother to try to pack and keep safe while travelling and something that is build around my body- as the most "aero" position of the rider is not the most sustainable.

5.6% would be pretty significant if you are saying you were sure you were able to keep constant position, wind, wind angle, Actual power (since a average over that distance could really be a completely different effort level if there was any physical variance.

Unfortunately, there are too many variables to say what is the issue. It might not be the frames at all that are different, but instead simply your body position. Getting a bike fit doesn't guarantee you will be put into a more aero position. Without before and after photos for comparison, it is hard to say. Not to mention that your wheels/tires might have been different, etc.

Thanks for returning with the data. Couple of questions if you could get this info:

1. Pad height to road or floor surface (from both bikes) Takes a minute to get that # using a tape measure. I am going to guess around 36"- but within the 1/8" tolerance if you can.
2. Same pedals for both bikes?
3. Seat height. If you line the two bikes up side by, is one seat higher than the other? You can use a carpenter's level if you are unsure.

The comment on cost $. Not really factors into the equation. There should be no reason why that Guru can't be as fast or faster for you.

---

Training Tweets: https://twitter.com/Jagersport_com
FM Sports: http://fluidmotionsports.com

You need to know the BB drop and crank length too, to do what you are trying to do.

You will note, no dramatic performance differences caused by carbon layup, despite his huge size which should amplify such considerations.

---

---

Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

Except of course, aerodynamics. That is a very real reason that the Guru may be slower than a six plus year old cervelo design...

What's even more ironic though, is the idea that you are now blaming his super special custom made bike's fit for being slower than his off the shelf cervelo. Hahahahahahahaha...

CR901 is getting closer to launch time - Di2 is in and cabled up working nicely. Battery will be on the seat tube.

Rear brake bolt, crank set spacers and have to make up a saddle. Bruce @ Island Cycle is doing the work.

---

Training Tweets: https://twitter.com/Jagersport_com
FM Sports: http://fluidmotionsports.com

That paint job is really nice looking, love that blue and black.

I apologize for the slow response. I had been out of town so I was not able to answer the questions that you asked. Now that I am home I was able to compare the bikes. If by pad height you mean the distance from the ground to the arm pads that distance is 40 1/2" on the Guru and 40" on the Cervelo. The seat height for the Guru seems to be about 1 inch higher than the seat height for the Cervelo. I have Look pedals on both bikes.

thanks for thumbs up on the color chapparal...

OK Guru vs Cervelo kinda what I expected.

You are sitting higher on the Guru, catching more air as a result.

Look pedals are probably the worst choice. You have to get as close to the pedal axle as possible, shoe + cleat combined. Speedplay perhaps or if you have Bonts, you could try our V-pedal, prototype #2.

Lower pedals you can move everything that pedal stack distance lower (seat + pads). Pedal stack is sole/shoe thickness, cleat and pedal to axle center. Some shoes are really thick!

If you put the seat the same and the pads, both bikes should be the same for speed.

---

Training Tweets: https://twitter.com/Jagersport_com
FM Sports: http://fluidmotionsports.com

Once again, measuring the pad to the ground is misleading, since those two bikes have different bottom bracket drop (P2 is 60mm and the Guru is probably 75). You need to measure the pads (and the seat height) relative to the bottom bracket. It is easy, now measure the bottom bracket height of the P2 and the Guru and subtract it from what you have already measured. It appears the the Cervelo is a much lower position.

GURU Update &further to the DIY disc build thread, I've been working through finishing the custom build today. I couldn't be happier with the quality stuff of this project.

We (Jay that is) cut a new aero pad platform in the shop - ultra low profile and linked so that the DI2 wiring finds a home under the center panel. And kept going down the middle with this real nice saddle leather. Leather is obviously old school and feels great! I was looking for a British flair to this bike (ala Wiggins, HED, vintage hour record etc.) but also high tech albeit on a "budget" build. I don't understand why aero pads aren't more of platform. On this I can go full narrow or a bit less than narrow. And my platform is 1/2 as thick as the odd shaped mini-stock ones that came with the bar

I could go over the parts list but there is surprisingly little $ for such an awesome bike. The frame rides beautifully, I can setup for a raging TT or raise it up for a six days riding. And it feels like a bike should vs a hyper speed machine, that would have no business going for some distance crushing. And in reality, once I complete the "aero-limbo" to spec, i think this bike will outpace the frenetic E118 simply due to shifting, and I'll be in a better position +/- 5cm here and there. I spent a lot of time measuring and selecting the stem and bars for example. I think their is truth to that philosophy of fit above aero compromises.



Guru $2000 (NOS/special price)
DI2 Kit $1000
Crank, brakes, chain: Mybikeshop: $300
CF Bars+ tape: $200 (Ebay)
BB+Stem (Ebay) $100
Elliot's HED wheel $300

---

Training Tweets: https://twitter.com/Jagersport_com
FM Sports: http://fluidmotionsports.com

Hello I just purchased a Guru 901 Frame and will transfer my Dura Ace Groupo over from my Guru Crono which has a Reynolds Ouzo Pro Fork should I keep the Guru 901 fork or is the Reynolds Ouzo Pro a Better component. Please give your view

I would stick to the stock fork. Swapping forks can change the handling dynamics. Based solely on pictures of the Reynolds fork I would guess the stock fork is more aerodynamic.