Go Back  Bike Forums > Bike Forums > Triathlon
Reload this Page >

Tri bike sizing

Notices
Triathlon Swim / Bike / Run your thing? Drop in our new triathlon forum for the latest in training & gear. From beginner to expert, and sprint to ironman.

Tri bike sizing

Old 03-28-22, 12:17 PM
  #1  
thehammerdog
Senior Member
Thread Starter
 
thehammerdog's Avatar
 
Join Date: Dec 2007
Location: NWNJ
Posts: 3,667

Bikes: Road bike is a Carbon Bianchi C2C & Grandis (1980's), Gary Fisher Mt Bike, Trek Tandem & Mongoose SS MTB circa 1992.

Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 707 Post(s)
Liked 323 Times in 211 Posts
Tri bike sizing

I am aout to buy a new to me Tri bike. size 54....I ride a 56 road but was schooled on you can go down size for tribike.
Scattante t560 Dura ace looks good.
crap wheels but I have sweet old pair of Rolph..original Ti.wheels light smooth.
Any thoughts on sizing. not yet seen bike.
thehammerdog is offline  
Old 03-28-22, 01:17 PM
  #2  
burnthesheep
Newbie racer
 
Join Date: Feb 2018
Posts: 3,271

Bikes: Propel, red is faster

Mentioned: 33 Post(s)
Tagged: 0 Thread(s)
Quoted: 1505 Post(s)
Liked 1,451 Times in 906 Posts
No idea. See if you can find the manufacturer fit chart. It's a chart where on one axis it has bike frame size increasing and usually the other axis has all your fit coords: reach, stack, crank length, etc........ Usually the middle sizes have a lot of overlap in all the fit coords.

If you have a bike fit from a local place, you can apply that against what you see in the chart to make sure you're good to go.

People get smaller frames IF it allows them to run a lower stack AND they desire to. 90% of tri/tt bike riders simply can't even ride the larger bike with more stack at the lowest stack height as a starting point anyway. So going all super low doesn't get them anything.
burnthesheep is offline  
Old 03-28-22, 05:44 PM
  #3  
thehammerdog
Senior Member
Thread Starter
 
thehammerdog's Avatar
 
Join Date: Dec 2007
Location: NWNJ
Posts: 3,667

Bikes: Road bike is a Carbon Bianchi C2C & Grandis (1980's), Gary Fisher Mt Bike, Trek Tandem & Mongoose SS MTB circa 1992.

Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 707 Post(s)
Liked 323 Times in 211 Posts
Originally Posted by burnthesheep View Post
No idea. See if you can find the manufacturer fit chart. It's a chart where on one axis it has bike frame size increasing and usually the other axis has all your fit coords: reach, stack, crank length, etc........ Usually the middle sizes have a lot of overlap in all the fit coords.

If you have a bike fit from a local place, you can apply that against what you see in the chart to make sure you're good to go.

People get smaller frames IF it allows them to run a lower stack AND they desire to. 90% of tri/tt bike riders simply can't even ride the larger bike with more stack at the lowest stack height as a starting point anyway. So going all super low doesn't get them anything.
it an older bike scattante performance brand 9 speed dura ace....i cannot find any info..2010ish year.
thehammerdog is offline  
Old 05-04-22, 04:07 PM
  #4  
VegasJen
Senior Member
 
Join Date: Dec 2021
Posts: 194
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 168 Post(s)
Liked 91 Times in 55 Posts
What does this mean, "stack height"?

I'm seriously considering finding a tri bike. I've done four tris so far, all on regular road bikes. I use clamp on aero bars, more for comfort/endurance than actual aero. But I rarely use the drops so I'm thinking about just jumping to a dedicated tri bike.

So what are the advantages of a dedicated tri bike over a road bike anyway? The one thing that worries me is the angle. Even on my road bike with aero bars, I get an awful crick in the neck if I'm down on my bars for a long time. I understand the tri configuration is flatter than a road bike. Is this true? I can't imagine bending my neck much further and not having some serious pain after a long ride.
VegasJen is offline  
Old 05-05-22, 08:44 AM
  #5  
burnthesheep
Newbie racer
 
Join Date: Feb 2018
Posts: 3,271

Bikes: Propel, red is faster

Mentioned: 33 Post(s)
Tagged: 0 Thread(s)
Quoted: 1505 Post(s)
Liked 1,451 Times in 906 Posts
Originally Posted by VegasJen View Post
What does this mean, "stack height"?

I'm seriously considering finding a tri bike. I've done four tris so far, all on regular road bikes. I use clamp on aero bars, more for comfort/endurance than actual aero. But I rarely use the drops so I'm thinking about just jumping to a dedicated tri bike.

So what are the advantages of a dedicated tri bike over a road bike anyway? The one thing that worries me is the angle. Even on my road bike with aero bars, I get an awful crick in the neck if I'm down on my bars for a long time. I understand the tri configuration is flatter than a road bike. Is this true? I can't imagine bending my neck much further and not having some serious pain after a long ride.
Tri bikes often have a longer wheelbase or a longer chainstay to ease the handling a bit, less twitch.

Next up the stack is how far you can raise or lower the bars. Up/down. So road bikes that are aero racers have shorter head tubes and 'less stack' than endurance geometry with taller head tubes and "more stack". Adding stack on a road bike would be inserting the spacers under the stem. On a tri bike it is either doing the same thing OR adding spacers under the elbow pads depending how the bar is built.

The tri bikes keep you from having a rough hip angle due to the seat tube angle also. Most tri bikes have a steeper seat tube to bring the saddle forward. Which is good.

As for the head/neck thing, you either need to do some exercises to help with it OR ride the bike enough to develop the muscle memory to get comfy in it. This is all relative though. If you're on a really aggressive fit and your neck hurts to look down-road, sure, raise the stack up. If you're already on a high stack and still can't do so, I'm not sure a tri bike is a good idea.

But, you can find the "fit chart" for the bike you want. Usually is a diagram showing how they measure each dimension. Find the stack and reach for your size frame. Write it down. Go measure that same dimension on your road bike the same way the picture they have shows it on the tri bike, to the arm pads of your clip ons. Then compare. Does their fit chart say the stack can go equal or higher than your road bike currently is? Same for reach. That's what you need to know.

Stack is shown in this chart:

burnthesheep is offline  
Old 05-05-22, 09:18 AM
  #6  
VegasJen
Senior Member
 
Join Date: Dec 2021
Posts: 194
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 168 Post(s)
Liked 91 Times in 55 Posts
Thanks for the explanation. I'm going to have to chew on that for a bit to digest it all. As far as the neck hurting, at this point, it's more arthritis than anything else.
VegasJen is offline  

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright 2021 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.