Triathlon - Excessively small tri frame compared to your road frame?

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Trainingwheels
08-15-07, 10:10 AM
I was wondering if anyone rides a tri frame that is 4 to 5 cm smaller than their road bike? I ask because most feed back says a frame size smaller depending on the manufacturer. I ride a very aggressive aero position and was wondering if it could be detrimental to power. It is not uncomfortable and I'm able to stay on the aero bars the whole bike ride. Also, the first time I used it in a sprint was the first time my hamstrings did not cramp and my run time dropped by just under 3 minutes.


bvfrompc
08-15-07, 10:19 AM
I was wondering if anyone rides a tri frame that is 4 to 5 cm smaller than their road bike? I ask because most feed back says a frame size smaller depending on the manufacturer. I ride a very aggressive aero position and was wondering if it could be detrimental to power. It is not uncomfortable and I'm able to stay on the aero bars the whole bike ride. Also, the first time I used it in a sprint was the first time my hamstrings did not cramp and my run time dropped by just under 3 minutes.

I go with a 60cm road, 58 tri. I was fit in SLC by the same guy that works with Dave Z, so I guess he's pretty good.

cslone
08-15-07, 02:54 PM
It is not uncomfortable and I'm able to stay on the aero bars the whole bike ride. Also, the first time I used it in a sprint was the first time my hamstrings did not cramp and my run time dropped by just under 3 minutes.

Well then I guess it works, doesn't it! :D

And to answer the question, my TT bike is is 3cm shorter.


Dalai
08-15-07, 10:22 PM
I was wondering if anyone rides a tri frame that is 4 to 5 cm smaller than their road bike? I ask because most feed back says a frame size smaller depending on the manufacturer. I ride a very aggressive aero position and was wondering if it could be detrimental to power. It is not uncomfortable and I'm able to stay on the aero bars the whole bike ride. Also, the first time I used it in a sprint was the first time my hamstrings did not cramp and my run time dropped by just under 3 minutes.

I am currently building up a NOS Alloy Cervelo P3 52cm after riding a friends 52cm Alloy P3. I was sceptical with such a large drop in frame size at first as I ride 56-57cm road bikes, but I his bike out for a fast 60km ride and it fitted perfectly for me though in a very aggressive riding position.

tajsss
08-16-07, 10:14 PM
I currently have a 58cm road frame ( free but a tad big). I should probably be on a 56cm. I got my first tri bike in May and ended up with a 52cm QR Kilo. Anything in a 54cm I tried was too damn big. I am 5'11" by the way. Apparently I have a short torso and long legs. My friend who got me fit and setup at my LBS was shocked a 52cm fit so well. It is an extremely aggressive position for the shear fact that the short frame a small headtube and my seat has to be cranked way high for my long legs. I am slowly getting used to it. My back did not like it much at first but it is getting better.

I have heard there is a point where too aggressive can decrease power but I feel I had no better choice with my sizing. Now if you are purposely setting your bike up over aggressively trying to get out of the wind, you might be hurting power so much it hurts you more overall. This might be when it is time to get out a power meter and do some testing with positions and power output. If you got a bike that fits though, that's the best start. You can always play with adjusting the position on your current bike a little here and there to see if you can get more power out of it.

The only downside may be if you are doing really long distance and plan an IM. Those guys don't ride quite as aggressive because they are going to be on the bike for so damn long. If you are sticking with shorter races, no worries.

Trainingwheels
08-20-07, 09:41 AM
Thanks for your input. Using a power meter and making small adjustments may be the next step.

merlinextraligh
08-20-07, 10:01 AM
Thanks for your input. Using a power meter and making small adjustments may be the next step.

A good bike fitter that understands triathlon / time trials, can do a performance fitting for you.

They measure your power output with a power meter, and calculate wind resistence from measurements.

Heard stories of people shaving minutes off their times, and not always from lowering their position.