HiYoSilver
12-15-05, 10:01 AM
If you want to put aero bars on your bike, do you make sure the seat angle is about 75..76 degrees or not?
Framebuilders - What seatpost angle is best?
Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.View Full Version : What seatpost angle is best?
king koeller
12-15-05, 11:27 AM
i believe you're refering to the seat tube angle and not the seat angle. the Seat angle is always level or parallel to the ground. With the exception of a brand new Brooks Leather saddle, i always tip the nose down the tinest bit(2-4mm).This helps to relieve pressure on a new saddle.
Now for frame building, look at detailed photos of bikes that you want to pattern your frame after and measure the angle of the seat tube in the photo. Aero bars are used primarily for timetrails and ironman style triathelons. Look made a nice time trial bike with aerobars and the seat tube looked to me to be closer to a 74.5 or 75. Keep in mind that the body is shifted forward almost in front of the crank.
Check out the different bike companys frame geometry spec's.
good luck
Now for frame building, look at detailed photos of bikes that you want to pattern your frame after and measure the angle of the seat tube in the photo. Aero bars are used primarily for timetrails and ironman style triathelons. Look made a nice time trial bike with aerobars and the seat tube looked to me to be closer to a 74.5 or 75. Keep in mind that the body is shifted forward almost in front of the crank.
Check out the different bike companys frame geometry spec's.
good luck
HiYoSilver
12-15-05, 01:01 PM
i believe you're refering to the seat tube angle and not the seat angle.
You're correct, unfortunately I don't know how to change the subject line of a thread.
Question still is: if using full length aero bars, then does the 75-77 seat tube angle allow proper breathing, ala,
Tri bike, vs 72-73 of road bike.
You're correct, unfortunately I don't know how to change the subject line of a thread.
Question still is: if using full length aero bars, then does the 75-77 seat tube angle allow proper breathing, ala,
Tri bike, vs 72-73 of road bike.
lala
12-15-05, 01:17 PM
I fixed the title for you.
HiYoSilver
12-15-05, 03:08 PM
thanks lala
king koeller
12-16-05, 12:43 AM
there is just so many other factors to consider....
1. top tube length.
2. Saddle fore and aft adjustment...
3. stem extention and rise of your aero bars
4, height of saddle...
5. wheel base of overall frame and fork...
This is why i love all bicycles, so many factors and possibilitys!
Good luck!
1. top tube length.
2. Saddle fore and aft adjustment...
3. stem extention and rise of your aero bars
4, height of saddle...
5. wheel base of overall frame and fork...
This is why i love all bicycles, so many factors and possibilitys!
Good luck!
HiYoSilver
12-16-05, 09:36 AM
why? I would think all that matters is:
1. seat tube angle
2. height of seat vs height of bars
Others will effect how the bike rides, but not how you feel when pedaling in a more laid out position.
1. seat tube angle
2. height of seat vs height of bars
Others will effect how the bike rides, but not how you feel when pedaling in a more laid out position.
FarHorizon
12-18-05, 09:02 PM
why? I would think all that matters is:
1. seat tube angle
2. height of seat vs height of bars
Others will effect how the bike rides, but not how you feel when pedaling in a more laid out position.
Actually, they make bizarre "Tri seatposts" intended specifically for use with aero bars. If the seat tube angle isn't upright enough to provide proper fit and extension over the bike, the tri-seatpost has a forward-set seat clamp!
This forward-set clamp moves the rider forward over the frame, allowing a variety of fit adjustments. Looks strange, but it obviously makes sense for aerobar/triathlon use.
Ideally, you're right - the seat tube angle should be significantly more upright than a standard road bike to facilitate proper fit with a torso-forward, aerodynamic posture. Same with bar height vs. seat height, but obviously, some adjustments are still required.
1. seat tube angle
2. height of seat vs height of bars
Others will effect how the bike rides, but not how you feel when pedaling in a more laid out position.
Actually, they make bizarre "Tri seatposts" intended specifically for use with aero bars. If the seat tube angle isn't upright enough to provide proper fit and extension over the bike, the tri-seatpost has a forward-set seat clamp!
This forward-set clamp moves the rider forward over the frame, allowing a variety of fit adjustments. Looks strange, but it obviously makes sense for aerobar/triathlon use.
Ideally, you're right - the seat tube angle should be significantly more upright than a standard road bike to facilitate proper fit with a torso-forward, aerodynamic posture. Same with bar height vs. seat height, but obviously, some adjustments are still required.