t/t-tri bikes

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t/t-tri bikes

Postby Parrott » Tue Jun 12, 2007 9:25 pm

Just finished a weekend of racing and was doing alright until the final team time trial section. We lost 2 minutes on this and slipped well down the list. One of the riders in our team rode a time trial bike and was significantly faster on this than he is on a normal road bike. The team that posted the fastest time also had a rider who specialises in time trials and triathlons on a high end time trial bike. It appears that bikes with more upright seat tubes and a laid out riding position give a significant advantage over more traditional geometry in t/t events. Has anyone riden or owns one and can give any feedback? How effective will a set of time trial bars, reversing the seat post 180 degrees to move the seat forward and open up the hips, be on a normal racing bike?
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by BNA » Wed Jun 13, 2007 12:49 am

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Postby Mr888 » Wed Jun 13, 2007 12:49 am

Generally TT bike are a lot lighter and offer greater aerodynamics. I can only comment from a triathlon point of view.

I use to ride an "old" TT bike when I first started doing triathlons, but have found that the time advantages are not quite worth it. With today's much lighter and better geared bikes, attaching some tri bars will allow you to go almost as fast (I don't think tri-bars are not allowed in grade racing - triathlons are OK...can someone varify?). Personally I've found that the TT bike only gave me an average 30 seconds to 1 minute advantage over a 10-15km ride. The advantage is too easily loss with a bad transition, so it's better to work on these or the otehr disciplines.

Also I find that the riding position is quite uncomfortable, especially of the course is long. The TT bike will have you sitting (well it seems to me) with your butt higher than your head. You are forced into a tuck position and you put a lot of pressure on the shoulders and arms, and your back get sore. Breathing then becomes laboured, and you find you don't have much left in the tank for the run (that's me speaking)

Control is a lot harder as well compared to the standard road bike, so if the course is tricky with sharp turns you might actually end up losing time because you have to slow down to manuvour.

In my last triathon clun race a few months back, the time gap between the fastest rider and slowest was around 3 minutes over a 20km ride. Both TT bikes and traditional bikes were raced. A 3 minute advantage is not a lot considering the swim, transitions and run phases as well

If you're truely thinkinkg of using one for triathlons, do so after you've peaked in the other disciplines including the transition.
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Postby LuckyPierre » Wed Jun 13, 2007 7:28 am

Mr888 has said it all - the specialist geometry and positioning on a tri- / tt bike will give an advantage, but what you gain on the swings, you might lose on the roundabout. Your ride leg gain can be easily wiped out by poor transitions.
We aren't allowed to use tt bikes / bars in normal road races, but in our club tt's, anything goes. I find that there is a worthwhile advantage in using 'aero-bars', so I do (clip-on Profile aero bars). Yes, it puts more pressure on your position - but the secret is to relax and enjoy it. :? In the tuck, your weight is supported more directly on the bars, and, if you can, you can relax more and focus on your pedalling. The aero position reduces wind resistance too. I don't bother with changing my seat position, as we don't do many time trials.
Try some aero bars - borrow them if you can, and see how you feel about them.
Last edited by LuckyPierre on Tue Jun 19, 2007 9:43 am, edited 1 time in total.
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Postby sogood » Wed Jun 13, 2007 7:39 am

Mr888 wrote:Personally I've found that the TT bike only gave me an average 30 seconds to 1 minute advantage over a 10-15km ride.

That could be a healthy win in the context of an ITT outside of Triathlon.
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Postby Parrott » Wed Jun 13, 2007 5:31 pm

sogood wrote:
Mr888 wrote:Personally I've found that the TT bike only gave me an average 30 seconds to 1 minute advantage over a 10-15km ride.

That could be a healthy win in the context of an ITT outside of Triathlon.


We lost 2min over 24k, I am wondering how much was due to the other teams having tri bars and bikes. I have done a bit of sussing out over the net and have come up with the general rule is that on a tri bike you present a smaller frontal area to the wind. = less drag = less work= compounding advantage the further you go.

Cant afford a tri bike so I'm going to try some clip ons and modify a seat post to reverse it and move the seat forward. Not to worried about comfort as 24k seems about our longest t/t and apparently they are not to bad when working at or near max effort.
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