76 or 80 degrees?
I just got a new bike and am setting it up now. It's got a dual position (76/80) seatpost. On my old bike, I rode 80 but thinking about trying the 76 now. What do you guys do for IM races?
Matt
0
I just got a new bike and am setting it up now. It's got a dual position (76/80) seatpost. On my old bike, I rode 80 but thinking about trying the 76 now. What do you guys do for IM races?
Matt
Comments
*In general*, the forward position is better as Jeff says. If you can imagine an angle set by your ankles, hips and elbows (or shoulders...doesn't matter for purposes of discussion), you can see why. The 80 position moves your hips forward relative to your ankles. If you don't change the vertical height of your elbows/shoulders but do allow them to move forward/backward, you can easily see that the forward hip position and a somewhat more forward elbow/shoulder will provide a less acute hip angle (more "open" it's usually called). This means that you can afford to be lower in the front with the more forward saddle. Again, in general, lower = better because of aerodynamics.
There are also arguments about what parts of the leg are engaged in the bike propulsion with the more forward position (not fatiguing run musculature as much) but that, of couse, is less obvious.
Not much else to add other that another plug for Todd at TT bike fit. I had a great experience in getting recommendations and sizing for a new bike. I will be going back for a fit this spring before my IM plan starts.
Gordon
Yes, forgot to add he helped me pick the frame size as well as the proprietary stem size for my Trek SC and then fitted me on it at a discount as he had done my previous bike too. I sure didn't want to buy the wrong size stem as they are NOT adjustable!
@Trent He used video from my Pinarello fitting to determine I need a size L w/ 100/10 stem. Say, I have a nice Montello for sale. Late 2008 ridden 2 seasons for sale...LOL.