TT bike geometry calculator? Comparison to road bike?

Xplora · Postby **Xplora** » Fri Apr 18, 2014 8:38 pm

Is there a TT bike calculator out there? More importantly, is there anything that lets you pump in the current settings on a regular road bike, and spits out the equivalent TT bike?

Noticed a lot less finesse in the TT bike market, and I'm considering just throwing an adjustable stem on my commuter anyway to get the bars SUPER low.

thearthurdog · Postby **thearthurdog** » Sat Apr 19, 2014 6:45 pm

Most bike manufacturer sites list their sizes and geometry - not sure if that is useful to you. The UCI rules make bike measurements critical if you are a taller rider.

Don't get too caught up on being super-low; it's not all its cracked up to be.

Xplora · Postby **Xplora** » Sat Apr 19, 2014 7:56 pm

Low is relative

I think adjustable stem for 50 bucks is the winner. Maxed out I can drop the bars 3 inches and an inch closer, I already hit my knees on the arm rests when climbing on the bike (backyard bike mechanic solution with my bontrager tri hard bars) so will surely be enough on a madone.

toolonglegs · Postby **toolonglegs** » Sat Apr 19, 2014 8:00 pm

I just use a camera ... back parallel to ground, forearms as well, then make it fit. Agree that it isn't that easy when you are tall!... I need the extra 5cm they give us with an exemption... but could do with an extra 2 to stop my knees hitting my elbows

.
Just start with saddle nose 5 cm behind the bb at the right height and go from there.
Not that I have ever had my bike measured but one day it may happen.

Xplora · Postby **Xplora** » Sat Apr 19, 2014 8:13 pm

I am a bit worried about the saddle actually. Using an Smp almost maxed out forwards, doesn't give much wriggle room

Haven't had issues with elbows on knees before?? Clearly haven't pushed the envelope enough!

toolonglegs · Postby **toolonglegs** » Sat Apr 19, 2014 9:04 pm

I am using an ISM so compared to a normal saddle I am really far forward. Keeping the ski poles at 80 cms max in front of the bb is pretty tough. Setting up my new TT now, might have to compromise a bit and bring the saddle back a touch... But like I say I have never been measured, so probably get away with 84cm, but if someone suddenly suddenly told be to make it fit to UCI specs I would be screwed, hence trying to get as close to legal as poss.
My issue is my groin / hip flexors... Get to low and my right leg starts kicking out, if I can sort that I will be laughing.
Hey Arthurdog, your the same height as me. What's you set up measurements?... And what's your power like TT compared to road?.

thearthurdog · Postby **thearthurdog** » Thu Apr 24, 2014 11:07 am

Not sure about all of the measurements off the top of my head. My bike gets UCI checked all the time so I am 6.5cm behind bottom bracket (can't get back any further) and right on 80cm for the extensions. That position still feels 'squished' to me but at 193cm with draconian UCI rules I'm not alone. I ride a 'moderate' amount of saddle to handlebar drop so I am not super low. I find that this reduces the 'squishing' effect somewhat. With regard to power I would estimate that my TT bike is 5% lower than my road bike. I am hoping to narrow that gap as time goes on. It was much higher at one point.