thehammerdog

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.

burnthesheep

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.

thehammerdog

it an older bike scattante performance brand 9 speed dura ace....i cannot find any info..2010ish year.

VegasJen

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.

burnthesheep

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:

VegasJen

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.