Question about TT/Tri bikes



splinterhead

New Member
Dec 30, 2004
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Can someone please explain to me the difference, if any, between a time trial bike and a triathlon bike?
 
basically, tt and tri bikes are the same. the difference, if there is any, is in how steep you ride the bike. triathletes like to ride steep - seat tube angle about 76 degrees or more (up to 80) - so the transition to the run is easier. most pro roadies like to keep the seat tube angle close to their regular road bike angle, about 73 degrees, so they don't have to get accustomed to a different fit. in keeping with this practice, the trek tt bike from a year or so ago had a set tube angle of 74 degrees as opposed to most other tt/tri bikes which have steeper seat tube angles. my tt bike is now set up at about 76 - 77 degrees, down from almost 80 last year, while my road bike is 73. but that's just me and your needs will probably differ.


there's some good info in the article referenced above if one takes the time to read it. tom demmerly knows quite a bit about cycling and equipment.
 
rv said:
basically, tt and tri bikes are the same. the difference, if there is any, is in how steep you ride the bike. triathletes like to ride steep - seat tube angle about 76 degrees or more (up to 80) - so the transition to the run is easier. most pro roadies like to keep the seat tube angle close to their regular road bike angle, about 73 degrees, so they don't have to get accustomed to a different fit. in keeping with this practice, the trek tt bike from a year or so ago had a set tube angle of 74 degrees as opposed to most other tt/tri bikes which have steeper seat tube angles. my tt bike is now set up at about 76 - 77 degrees, down from almost 80 last year, while my road bike is 73. but that's just me and your needs will probably differ.


there's some good info in the article referenced above if one takes the time to read it. tom demmerly knows quite a bit about cycling and equipment.
So I take it you're adjusting your effective seat tube angle by altering the amount of setback on the saddle. Are you measuring from the bb to the center of the seat post clamp or to some point on the saddle?
 
artmichalek said:
So I take it you're adjusting your effective seat tube angle by altering the amount of setback on the saddle. Are you measuring from the bb to the center of the seat post clamp or to some point on the saddle?

I went by this...

http://www.slowtwitch.com/mainheadings/techctr/anglefinder.html

but now it looks like its been modified to this...

http://www.slowtwitch.com/mainheadings/techctr/anglevangle.html

which may make it a little different. I'd have to run the new calculations.
 
meb said:
I'll hold off explaining unless someone better situated to distinguish fails to chime in with a good articulation.

That last sentence contained exquisite articulation of its own. ;)
 
Thanks for all the help...I ran a lot through the winter and have been looking to get in some duathlons and maybe some local time trials this summer.