mazdaspeed

Say it's a 10 mile TT, normal road bike vs. TT bike with TT helmet and wheels...

How much of a time/mph difference are we talking here? Will the difference be the same for a weaker vs. stronger rider?

Stallionforce

Check out the sticky on this topic.

If you're rockin' a road bike without clip-ons, without a TT helmet, without a skinsuit, or booties -- forget it: you're going to have to put out a lot more watts than a dude in a full aero position with all the goodies.

however, I know lots of guys who can get an excellent TT position on a road bike, although it generally has to have a shorter top tube (only so much ramming forward of the seat works). If you race a few you'll start to get the idea: TT'ing is a discipline that you learn to perfect in micro adjustments over a period of years. Just ask DrWJO.

The fitness benefit, however, is enormous -- you just cant push yourself at home doing LT 2x20's the same way as you can in a club TT even if you're just in the drops with a normal helmet, bibs and jersey.

I'd say, bottom line: beg, borrow, or steal a pair of clip-ons and a TT helmet. Position first, then helmet, then... (Go check the sticky!).

And good luck, they're worth doing even if you don't have optimal equipment just for fitness, as I said.

daytonian

alot

gsteinb

More than spelling?

Dalai

One study published in the German Tour magazine Jan 2007

They put Uwe Peschel on a normal bike:

Needed Watts for Speed = 45 km/h :

Stevens San Remo bike with normal handlebar 465 Watts needed to go 45 km/h
Same bike Hands down the drops: 406 watts needed
Same bikeEaston Aeroforce bar: 369 Watts
Same bike Triathlon position (5.5 cm lower bar, saddle forwards): 360 Watts
Same bike Triathlon position (5.5 cm lower bar, saddle forwards) and
carbon Tri spoke wheels front and rear: 345 Watt

Cervelo (Alloy P3) + Tri spoke front 328 Watts
Cervelo + Tri spoke front + disk rear wheel : 320
Cervelo + Tri spoke front + disk rear wheel +Giro helmet: 317
Cervelo + Tri spoke front + disk rear wheel +Giro helmet + speed suit: 307
Cervelo + Tri spoke front + disk rear wheel +Giro helmet + speed suit +
saddle 3 cm further back: 293 Watts

MDcatV

signficant difference between "normal" road bike and tt get up.

example, I did a 12K TT as part of a stage race, no aero bits. I'm not a huge engine, but I'm OK, I got caught and passed by 2 dudes (30" behind and 1' behind) who were in full aero gear. I've raced against both these guys enough to know that they're both good racers, but not 30" to 1' better than I am in the power or power/weight department.

aero, it matters.

FatguyRacer

I would most definately agree with this.

I finally finished cobbling together my low tech budget TT bike last night and took it out for a test spin. For good measure I threw on a skin suit and wore my new Rudy Project Syton Comp TT helmet for the first time for the test run. Once i got warmed up I went to a flat road section near my house and cranked out some 1-2 min intervals. I was suprised at how fast I was going. I also suprised at how easy it was to go that fast. If I had had a disk wheel and a tri-spoke up front, I would have been going even faster. I was looking down at my speedo and it was reading 25+ mph at my LT or a little over and about 340 +/- watts.

Aero position + proper seat angle + TT helmet makes a big difference.

The 54/42 TT cranks with 175mm arms didnt hurt either. I may switch to 175mm cranks when I get my new bike road bike.

This is my only geared bike for the next 2 - 3 months. Im looking forward to the training.

SwimBike

https://www.socalttseries.com/Trainin...7/Default.aspx

within

Here is some anecdotal data I collected yesterday while comparing my road bike to my TT bike. I have had a tough time TTing and am trying to find my position early so I can spend plenty of time adapting to the position prior to next season. I tried to target a HR of 140 throughout each run. The info was recorded with a Polar 725.

The road bike is a 2006 56 CR1. The TT is a 2007 54 Plasma. I used the same wheels and tires/psi. Same clothes, etc...The road was a 4 mile circuit, more or less a circle. One stop sign on a 90 degree right hand corner was the only real place in the circuit that broke the rythm from run to run. The wind was calm or at least quasi as I kept eye on three flags around the circuit. I warmed up for just under an hour before I made the first run. 20 minutes or so elapsed between runs to change wheels and spin around on the next bike prior to the run.

Road bike/TT bike:

Circuit Length: 4.158mi/4.159mi
Lap time: 12:02.4/11:18.0
Avg speed: 20.5 mph/21.9 mph
Avg HR: 140/141
Ascent per lap 20ft/20ft
Temp: 82F/83F

I didn't have time to make more runs at time trial effort. A HR of 140 is zone 2 for me so I am not sure if this data really shows much other than I'm in a better position riding around on a TT frame at 140bpm...Not exactly sure why I picked 140 other than it's base and I was doing base that day.

FatguyRacer

If you interested in low budget heres what I did to my 1992 Trek 2100.

1. Profile seat post, the one with the forward bend. (60 bucks)
2. Profile T2/Cobra carbon clip-ons. (140 bucks)
3. Profile cowhorn base bar. (already had it)
4. 3T 100 mm quill stem. (10 dollars from the LBS used parts bin)
5. Dura Ace 9s bar end shifters (50 bucks used)
6. Rudy Project Syton Comp TT helmet (much less than retail, they're a team sponsor)
7. Campagnolo Chrono TT crankset 54/42 with 175mm arms (already had it)
8. no-name reverse pull brake levers (20 bucks for the pair)
9. Assorted cables and housings (30 bucks give or take 5 bucks)

I might get a wheel cover disc to keep the spirit of the low budget thing going. Maybe a Spinergy Rev-X front wheel If i can scoup one off ebay cheap enough.

I didnt spend alot to put this together which was the point. I dont TT near enough to justify the expense. Yet.

MDcatV

^John, thanks for posting this. I've got an older steel serotta frame that I'm looking to build into a "low budget" TT set up over the winter months, this is the kind of info I need to get going on such an endeavor. Since I will TT <5x/yr., MAX, spending a bunch of coin on a tricked out setup just doesnt work for me conceptually.

curiouskid55

Maybe 20 seconds on a flat course, not much on a hill tt.

StanSeven

I don't get this - saddle further back? Or does this mean the saddle moved to the most forward position on the P3 post?

daytonian

fail

sac02

This doesn't seem to conform to the advice given on a regular basis on this forum that an aero helmet is the best and first thing to buy after you get your body in TT position:

Tri-Spoke F&R: 15 Watts
disk rear: 8 Watts
[tri-spoke front & disk rear: 23 Watts]
helmet: 3 Watts
speed suit: 10 Watts
move saddle back: 14 Watts

Though like the poster above me, I also don't understand the "saddle 3cm further back"

Mac

rizz

And this is why they should force everyone to run on regular road bikes. Take away the ability to buy speed and everything events out. Who doesn't like close competition? Or add penalties for running aero gear. Oh yeah!

FatguyRacer

You welcome. I'll post a picture later tonight. It's a butt ugly bike, but it will get the job done.

Me neither. I can think of maybe 5x next year that I would TT. And 2 of them are Church Creek. The rest would be short stage race TT's. My rig will get me under an hour for a 40k with normal training. Thats all I really care about anyway. I'd rather spend the extra money on a set of deep dish carbon wheels that I can use on my road bike too.

urbanknight

If you're losing the time trial by minutes, it doesn't matter. If seconds, it does.

Incorrect. Alot is not a word in the English language.

BananaTugger

It's less about the equipment and more about the position the equipment puts you in.

mazdaspeed

This is interesting, thanks.

The reason I'm asking is because the University team I'm on will be doing TT's and I don't have a TT bike or money to buy one. Doing what you did, however, could be possible.

cedricbosch

Wow, that's impressive. Thanks for the info.

Keith99

I tend to agree. Just want to point out it will not be instand. In fact it is even possible to end up going slower. Just as in any other sport the advantages of changing technique are only fully realized after considerable practive and training.

urbanknight

Not sure if it's the same for anyone else, but I actually got slower for a few weeks after adding aero bars to my road bike because I wasn't used to using them. It took me a little while to get them adjusted correctly and then get used to using them to my advantage.

umd

I took a minute off a 10 mile TT on the second ride of my TT bike, which was just my old Allez converted to have full aerobars (bullhorns & barend shifters, not clipons) and a forward seatpost.

Dubbayoo

+1. Even with a fan right on me I can't hit nearly the same watts indoors as I do outdoors. I even spin 15-20 rpm faster outside.