Time Trial Bike Vs Road Bike: What’s The Best Triathlon Bike For Descending?

Time Trial Bike Vs Road Bike: What’s The Best Triathlon Bike For Descending?


What is the best bike for triathlon? Could your bike leg be faster in your next triathlon? GTN’s ex-pro triathlete Mark Threlfall puts road bike vs TT bike to the test descending on hilly terrain.

For flat triathlons, your choice of bike is probably clear. But, what about hillier events? Is there really an advantage to a super aero time trial bike or would you be better (given the choice) on a lightweight road bike?

In a previous video we have shown that the TT bike can match the road bike climbing, but what about descending?!

This is the ultimate test of TT setup vs road bike. If a TT bike can match a road bike on a descent as well as a climb, then we’d suggest that a TT bike is definitely the best bike for a hilly course. But, if a road bike is significantly faster, that makes things more complicated!

To put our theories to the test on this one, Mark rides his Cervelo S5 and then Cervelo P5X down San Salvador in Mallorca.

What are your predictions for this one? Let us know down in the comments and don’t forget to like, share, subscribe and set notifications.

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  1. I would like you guys to be using something that doesn't have blip shifters on the brakes. Something with a mechanical group set perhaps vs a road bike. I know I can't afford a $10,000+ tri bike like the p5x. This would be especially important on a climbing video as well.

  2. Didn't use aerobars for the majority of the descent, didn't equate wattage and as he said, one bike had disk brakes. This test was a joke. A test should have ONE VARIABLE no matter what is being tested.

  3. Ideal solution, put aero bars on your road bike? Best of both worlds in this scenario.

  4. wtf the frames are too small for bim

  5. Just one run for each bike i not enough. Although I presume that you have ridden San Salvador a "few times" in the past, I would still expect you to be faster on the second run simply due to the insight into the course and line gained from the first run. You should have done multiple rides with each bike, switching the bike after each run to smooth the effect. And a "descending test" should not include the flat part at the end; that skews your result…

  6. Is that slow motion in the corners? 😉 I would be interested in the strava-times.

  7. Both bikes need same brakes, same wheeles/tyres' and similar weight for such a test to mean anything. Also, you need to do mulriple runs for each bike. Otherwise, its kind of pointless to make any conclusions.

  8. John Tran Official

    Holy cow the cornering from this fella is bad.

  9. Best option: road bike with TT arrow bars added atop of classic road bars.

  10. what if you put TT bars on a road bike?

  11. How big is that piece of cake ??!!

  12. Martijn Roozendaal

    May I suggest that when you do these kind of comparisons and tests that you do it properly. At the end of the video you are already saying why this is not a good test because of the disc brakes and the type of decent. I hope for higher quality and more informative content on this channel.

  13. I hope Mark did more than the downhill exercise to justify that slab of chocolate cake!

  14. On your first video i've ask you to let me change my mind about triathlon and make me in love with it, not to show me sponsored "kinda" test's, for that gcn presenter's do it better and with Matt clipless pedals war and Lasty real climbing faces

  15. #askgtn I have flat feet. In stability running shoes my ankles are neutral when I heel strike, but I can't tell if they help when I'm running on the mid-foot or toe. I don't want to keep buying expensive and heavy stability shoes if they're not helping.

  16. Sam Hellebrekers

    I think that what bike you're used to be riding also has a major influence

  17. Fascinating…i would of thought TT much slower on bends. Just goes to show! Mind you, what is price difference between two bikes?

  18. Would love to see GTN and GCN use D.C. Rainmakers analysis tool for these rides so we can visually see where the differences were on these tests

  19. Can you guys feature IM courses as well

  20. Average watts for each run? How can you compare if you don't state the power output? Also that looks like a pretty long straight section at the end…

  21. I like the comments you made comparing/contrasting your ride experiences on the two bikes. The final time is important, but having those comments gives an interesting perspective. It would be great to add another presenter to these comparison tests to get a little bit more data and anecdotal perspective. Thank you for the interesting video!

  22. Wow he can clip in even better than Matt!

  23. What was the wattage average? The results could be screwed up because of placebo. You may have thought the TT bike would be faster, so in turn, you would push harder. There also could've been problems with going to same distance. .01 miles could've made all the 6 seconds. Great video ideas, but you're going to need more evidence in them.

  24. So, it's OK not to have a TT bike and ride at any road of your choice.

  25. bicycle racing part's tester

    For correct results you should use the same wheels,and the same tires!You did wrong test!Even just tires can make big difference! https://youtu.be/KSZrCtVXUaw

  26. Great insight guys but I'm pretty sure I watched this on GCN 👍😎

  27. He isnt even a pro or as ever been a pro, at least have or get a pro triathlete to conduct these tests.

  28. Krzysztof Kajetanowicz

    I gather from the huge brownie in front of Mark that he had to cycle back up that hill between the two descents, rather than being bussed?

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