Friday, June 11, 2010

Trek's White Paper 2.0 - The Speed Concept

(Courtesy of and Trekbikes)

On Oct 23, 2007, Trek released their first white paper to the public after some debate concerning their Equinox TTX and its performance in the wind tunnel were called into question. At the time, our publisher, Dan Empfield, wrote that, "Trek Bicycle Corporation has granted's readers transparency atypical in the bike industry. Trek's Damon Rinard has penned a white paper describing the protocol and results of a recent wind tunnel test that, among other things, compares its bikes to two others in its competitive set." In the past two plus years, the level of transparency regarding wind tunnel testing has changed dramatically. Consumers - at least our readers - now expect to know how the bike they are considering buying stacks up - with hard numbers - against the competition. Employees from Blue, Cervelo, Felt, Kestrel, LOOK, Specialized, Trek (listed alphabetically) and others all participate on the forum. And the expectation is now that these individuals will make themselves available to answer questions about their products. At the risk of throwing him to the dogs, I will say that forum user "Carl" is the Carl Matson of Trek Bicycles whose name appears on this white paper. It was he who arranged for Slowtwitch to host this white paper. While neither he nor we can guarantee he will answer every question posed on our user forum, he has said that he'll do his best to avoid having any "chirping crickets" in threads about the SpeedConcept and this white paper.

The white paper can be downloaded by clicking here.

Simon says: -


Of course I'm bias but some interesting points I'd like to make. First of all, I think most would agree that the most popular tri bike around is the Cervelo. Some would say the P4C is the pinnacle others would say they already perfected it with the P3C. Either way they are fabulous bikes, attractive and aero and a great company behind them. However, in Trek's white paper for the TTX (Click here for my previous article on that white paper) the PC3 was in a clear second place to the TTX. Now you'll see in the graph attached that both the P3 and P4 are a distant way behind the Speed Concept.

Interestingly you'll note that the P4 actually has MORE drag at 15% yaw than the P3! (15% yaw is considered to be the benchmark of aerodynamic testing).

(Click on chart to enlarge)

Even more interestingly you'll note below from Cervelo's own testing that they had TWO MAJOR OMISSIONS: -

1)They only included P4 data up to 12.5% yaw!!!! What happened there, did they run out of wind tunnel time?

2) They included all the major brands EXCEPT TREK.

That says it all for me! I'm convinced - Give me a Trek Speed Concept over a P3 or P4 any day.

(Click on chart to enlarge)

Another interesting chart for you is the actual percentage and related time that you'd gain over a P4 using the new Speed Concept in an Ironman. It's a massive 10 minutes for a small rider and between 7 to 8 minutes for a medium rider like me. It may not seem like a lot of time but it's all "FREE" time and to think that I missed out on Kona qualification by 7 to 8 minutes!!!!! (I'm not blaming the bike though I was on a TTX so it was still quicker than the Cervelo).

(Click on chart to enlarge)

So in conclusion I've realised that I'm an average rider but my equipment makes me fast...hahahaha...actually my bike times speak for themselves and I average 400+k per week in training for 6 months leading to an Ironman, I work very hard at it BUT there is only so much that I can achieve physically so if I can make use of some "FREE" time I'll take it thank you very much!

And don't forget a disc wheel will make a difference but the best aero bang for your buck is an aero helmet - certainly cheaper than a new bike or a new disc and will knock minutes off your time.

Finally, sorry to all you Cervelo owners, I know there are lots of you and many that I ride with. This wasn't meant to be a Cervelo bashing article, I truly love the P3 and P4.

And look on the bright side, you have the third and fourth fastest tri bikes on the planet behind the TTX and now the Speed Concept, that's not bad is it?.


plee said...

Nice post! The white paper is really a nice read!Been a fan of computational fluid dynamics for awhile and really appreciate the math behind it. The Virtual foil continues to play its role well at the wider yaw angles..... and this appplies very much to the lower speeds of cyclists compared to Airfoils on cars or planes.

PS. no intent to discriminate among brands here.

jantel said...

Nice article Simon.
I have been following the bike since Lieto started on it recently.
One of my mates here in Singapore got one last week , apparently the first in Singapore ( unsure about SEA ) a black one. He pick sit up today.
I will be viewing it tomorrow night so will fill you in from there if you want.
Btw , I think you passed the "average rider" in tri anyways, a few years back :)

woei jye said...

hi i am woei jye, would like to be ironman as inspired me! can i know where ican get Trek bicycle in malaysia?

Brybrarobry said...

Those are VERY VERY interesting charts. I've been reading them when I have insomnia and they have been working like a charm, I'm asleep in no time. haha.


Simon said...

Paul, I'd never even heard of a virtual foil until I read this white paper - fascinating for sure.

Terry, I'm green with envy, I think Black Beauty is gonna have to be sold and upgraded pretty soon. Do give us some feedback on your buddy's Speed Concept.

Woei Jye, glad you're inspired, it's a great sport with great people in it. I've no doubt you'll be calling yourself IRONMAN in the not too distant future. You can get Trek bikes fro Ng Joo Ngan at Joo Ngan Cycles in Ampang. When you speak to him tell him you're a friend of mine and you're looking for a good deal and hopefully he'll set you up with a nice ride.

Bryan, I thought as much, I tried to keep it simple and put the graphs in to try to help you and the other Cervelo riders with learning difficulties. What bike did the fastest bike split in Kona last year???????

woei jye said...

Thanks Simon, i have learn a lot from you and will add you in my fb. so cool when you said "cervelo riders with learning difficulties", i agree with you.

jantel said...

Hey Gents,
I went for dinner at my mate's house and low and behold , thre she was in her stand 3 metres inside the front door , like a race horse.
Interesting seatpost. The actual seat can be clamped in two separate positions about 4 or 5 centimeters apart from each other making your actual position on the bike either VERY aggreassive ( guessing 80-83 degrees ) or slack 75-78 it appears.
Tremendous geometry and a very well thought out bike.The downtube in someways is similiar to my Blade but slightly sharper at the front. Great rear wheel cutout that really brings the rear wheel under you.
Intelligent hidden placement of the brakes although my mate was having problems with the rear and does not know how to fix it himself so perhaps some semi-advanced mechanical tricks should be picked up from the shop prior on this issue.
It has a shorter top tube than his previous bike ( P3C ) by about 4cm.
Comes with some wicked 3/4 deep-dish Bontrager spoked wheels which I personally love.
The bg point of course the cockpit.
Extremely adjustable for and aft , up and down , not so much on the narrowness of the aerobars which I like very narrow , but probably sufficient for 99% of the market.
Apparently you have a choice of close to ten stems to choose from to ensure your fit is optimum. BTW , I have never seen a stem like these. I actually was looking right at it looking for it :)
Weight wise it is not actually light and similiar in weight to my rig , but the aerodynamics as indicated in the YAW chart above and as my mate showed me again , is where the real investment comes in.

The little aero-box behind the seatpost comes with a little cloth bag by Bontrager and the compartment would fit a tube , wheel tools , CO2 cannister and keep your phone and money dry in training. It appears to be water tight and a feature that I like a lot for racing and training.

Summary , a sweet looking ride and apparently even though my mate was not 100% fitted properly, had no problem doing a 150km ride on Saturday morning at a pace that Simon would ride at !

I prefer the white colour selection myself and when I get healthy and racing again , hope to be able to race with one.
The only negative point I would add , is that behind the stem where it joins the headset , is a little cheap looking flap , that is inconsistent with the quality finish of the bike.


jantel said...

One last point , his wife did send me some pics she took.
I can forward them to you Simon if you give me your direct email and you can put them up or do whatever you wish with them.
Drop me a line @ if you wish :)



Simon said...

You've got to stop sending these updates Terry, they're going to result in my devorce or bankruptcy, probably both.

However, email is on it's way

jantel said...

Duly noted !