Saturday, May 7, 2011

New Bike Fit

3rd bike fit adjustment
just need a trainer, skin tight race jersey, and a protractor.

a good bike fit enable riders to ride comfortably for the desired distance at best performance. considering all fundamental aspects of rider's position, here i come out with my new bike fit. this is the 3rd time i change bike fit since the past 3 years. i have been trying on different position and angle, every alteration result in faster ride.

i do not want to go too aerodynamic which will strain my lumbar just like how the professionals do in Time Trial competition, neither do i want to expose my torso too much for comfort but have to work harder fighting wind drag.

recorded my body movement using Amirul's camera and captured my actual knee angle, hip angle and ankle when i ride in different position. this is way more accurate than capturing body posture when rider is static. when a rider is in static position, he will try to pose with the desired angle which doesn't simulate the actual condition when riding.

being a triathlete, i do have to consider my hip angle for better transition from bike to run. i need to consider aerodynamic, climbing and on the flat. this is the best alteration i can do to get the best of all. i'm not Retul standard of doing bike fit, i read from books and tried it out. do comment on my new posture.

Turquoise : frontal area exposed to wind drag. can be reduced by increasing height of seat post or drop down a few spacers. too aggressive aero position will cause back pain.

Yellow : Elbow angle should be within the range of 90 to 110 degree for extremely comfortable resting position, should be able to fall asleep on this position. in this case, i get 100 degree.

Pink : Torso angle, I get 30. important to generate maximum power to hammer the pedal.

Red : Poor knee angle will cause Iliotibial band syndrome.

Green : easier transition between bike to run. angle too steep will bring body to a very forward position which will result in great advantage on the flat as the center gravity of the whole rider and bike is channeled to the front. however, rider will lose speed in climbing. to balance both climbing and flat, i don't go too steep. mine is currently 80. it might be harder for road bike to get seating angle 80 as most road bikes come with seat tube 73 degree. my road bike is exceptional coz the seat tube itself is already 75 degree. very special geometry for road bike, and is the main reason why i bought this bike.

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