next seasons TT - n+1?

[mike]

am spending the afternoon on dull conference calls, pondering options for time trials next season. 

I cant justify a proper TT bike yet, but how much faster would I go over a normal road bike if I fitted profile bars & tribars to a steel framed bike?  and with the same wheels and fat bloke sitting on it, would it really be that much slower than a bling carbon TT frame?

Is there a table somewhere that shows the time gained by posh bike / pointy helmet / indecent skinsuit ? I could spend the afternoon window-shopping...

[David Martin]

am spending the afternoon on dull conference calls, pondering options for time trials next season. 

I cant justify a proper TT bike yet, but how much faster would I go over a normal road bike if I fitted profile bars & tribars to a steel framed bike?  and with the same wheels and fat bloke sitting on it, would it really be that much slower than a bling carbon TT frame?

Is there a table somewhere that shows the time gained by posh bike / pointy helmet / indecent skinsuit ? I could spend the afternoon window-shopping...

Gonzo will turn up with the right link in a moment...

But in short - tribars will take 60-90 secs off your time, or maybe more. You do a similar time to me and that was what I found.
Aero hat should take between 20-60 secs off.

..d

[Blah]

Yep, those two improvements are definitely the 'quick wins'. After that you're spending a lot more on more marginal improvements.

[mike]

is a posh bike only a marginal improvement then?  What about the expensive wheels?  [/wiggle]

[Greenbank]

is a posh bike only a marginal improvement then?  What about the expensive wheels?  [/wiggle]

I'm still planning next year's CF bike purchase (hello CycleScheme). At the moment it's between the Wilier Izoard Pro (Centaur) and a Ribble Scuro HCX with Centaur.

The wheelset on the Izoard Pro is (most commonly) Fulcrum Racing 3 although it seems to differ between individual shops.

The stock Ribble Scuro HCX with Centaur comes with Mavic Aksium. *spit*

I'm pretty sure I'm going to go for the Scuro HCX from Ribble with either Fulcrum Racing 3s or Mavic Kysrium Elites although for the list price of an Izoard Pro I could upgrade the Scuro to Mavic R-Sys SSCs

Yes, wheels do make a difference. Gonzo has the link with more details though.

[clarion]

If I turn up for a TT, it'll probably be on a 1981 Woodrup or a 1951 Rudge

[Greenbank]

If I turn up for a TT, it'll probably be on a 1981 Woodrup or a 1951 Rudge

I'm planning on doing my first few on the mudguarded Aravis Audax or the (90's steel) Colnago before I bring out the CF. Don't want to look like a complete "All the gear and no idea" twonk.

[clarion]

Exactly my strategy   Though I thin kthe Woodrup is cool enough to look serious without being overambitious...  A Colnago probably has the same effect.

[Greenbank]

Exactly my strategy   Though I thin kthe Woodrup is cool enough to look serious without being overambitious...  A Colnago probably has the same effect.

<resists GruB/.anth picture posting mode and just posts a link>

http://www.greenbank.org/bikes/colnago.jpg

[clarion]

Can I stroke it?

[mike]

 Mine's a red one:



(this will be the TT bike)

[Greenbank]

Seems my prompting worked.

Is there any particular reason why you've decided to use the Colnago instead of the Barrachi?

[mattc]

It's worth remembering that you can use tri-bars, a pointy hat and disc wheel(s) with your £100 531c fixed/14sp retro bargain. (I think most cool would be an old 10 speed with half the gears thrown away).

Also note that a clubmate just had a derailleur-wrapped-round-chain-stay incident on his carbon road bike. Result - 1 mangled chain stay

Oh, and the club 24hr record holder did it on a 1995 Raleigh with downtube shifters and a map-trap.

[clarion]

*hurt*

Actually, my Woodrup cost £103

[mike]

barrachi is for sale soon... ( anniversary present from Mrs Mike on the way  ) )

the colnago is a bit smaller, so there is more flexibility to get my arms a bit lower and I can take the compact off and fit a big chainring cos I wont need to do such big hills on it.  

Mattc - that's my other option. Keep the colnago as it is and get a 50 quid frame from ebay and build it up.

[mattc]

Mattc - that's my other option. Keep the colnago as it is and get a 50 quid frame from ebay and build it up.

Honestly, that's what I'd do. I assume you'll ride the Colnago many hundreds of exciting miles, up and down hill. You want comfort and a sensible gear range [whatever that means for you!].

The TT bike will just get ridden 10 miles a week max, mostly in 1 gear. It doesn't need to be complicated (or particularly comfortable).

[Blah]

The main reason for getting a dedicated TT frame is the steeper seat tube, which allows you to achieve a more forward saddle position, which in turn allows you be lower at the front. Flatter back = more aero more comfortably = faster.

After getting tribars and a silly hat, I'd go for a second hand proper TT frame.

After that you can think about wheels.

When you start thinking about wheels, anything with a rim less than 50mm is not considered aero. In other words, your Mavic SSC r-sys will be about as fast as a set of Mavic Aksiums, because they have a similar rim shape. The former may be lighter, but unless you're serious about climbing, that doesn't do you a whole lot of good. Decent aero wheels are considerably more expensive than the SSC's. Especially if you buy new. Decent aero wheels hold their value and so are still quite expensive second hand unless you are happy to buy heavy old stuff.

This was my thinking when I put my IronMan (on Sunday... gulp!) rig together. Got tribars. Got a pointy hat. Christmas bonus: second hand aluminium Cervelo on Ebay for a good price. Pay rise: nice wheels. My training wheels are Shimano 105 and they really are very nice. Probably faster than my Dura Ace on Open Pro 28 spoke jobs.

It's also worth bearing in mind that aero wheels only really kick in when you're sitting at 24 to 25mph. I've got an old Hed 3 on the back and a Hed Jet 60 c2 on the front (very painful to part with the cash for that one, but it's a very nice wheel). When I hit 24mph it's like a turbo, all of a sudden you slide into this almost effortless feeling, a bit like when a sailing boat or a windsurfer starts planing.

[Wobbly John]

I did last night's time trial on my fairly upright, steel fixie running a hub dymano. Took a minute and a half off my time, for that circuit, compared to earlier in the year on the Ksyrium wheeled geared bike.  

Aerodynamics may reduce your times, but the biggest returns come from preparation and the 'T' word*.



* Training  

[clarion]

Not having a hinge in the middle of your frame might help, too...

[mike]

John, please!  stop shattering my dreams of getting faster by n+1 !!

fair points all.  I guess I'll keep an eye on ebay and see what comes up over the winter.  It *would* be nice to keep the colnago for sunny days... 

If anyone wants me, I'll be the one sweating away on the turbo

[Frenchie]

Tri-bars do help a lot.

So do nice wheels.

Then a good fixie is all you need... and some training.

[mike]

   is there a Forum Standard for the 'frenchie lag time' between a new threat starting and Dr Frenchie posting about how more than 1 gear is a waste?   



(only kidding, mon brave - I will be trying a couple of TTs on fixed next year too, just for the cussedness of it )

[Greenbank]

After that you can think about wheels.

Very good points. I should have said that my plan is for more of a general purpose road bike rather than a TT specific bike.

[nmcgann]

is a posh bike only a marginal improvement then?  What about the expensive wheels?  [/wiggle]

A bike that lets you get into a seriously aero body position is a big improvement, it doesn't have to be bling. I went from a TT-ized road bike to a cheap TT bike (an old Giant TCR Aero frame that I built up) mid- this season and had good improvements on all the courses I regularly ride. Over a minute on rolling courses and two minutes+ on flat ones.

I use a powertap wheel so I know my power output hasn't changed, the gains are all down to aerodynamics.

I recently got a s/h Mavic Cosmic Carbone front wheel, but I haven't had a chance to see if it is making a measurable difference yet.

Neil

[gonzo]

Frame aerodynamics;
Here is about the only comparative study I've seen of different frames;
P3C = 690g of drag for a size 56 bike
Trek TTX = 690
P2C = 705g
Pinarelo = 705
Felt DA = 725
QR Lucero = 735
Kestrel Airfoil = 760
Kuota Kaliber = 780
Guru Crono = 790
Scott Plasma = 800
Orbea Oro = 810

The person
The entire bike system only represents about 20% of the total drag, the person represents the other 80% at racing speeds. For this reason, getting a good, low drag position is key. This is why a TT bike is really rather good.

Accessories
You may have heard the old myth about a time trial helmet is more important than aero wheels? Ignore that as it only holds true when there's no wind.

If you've got a TT specific steed, you can have dedicated tt bars which is nice and lets you shift while stretched out. As other have said, TT bars are the best improvement. Most importantly, get used to the position over the winter as the more aero you get, the lower the power you put up. You need to find the combination that gives the greatest watts/grams drag for you.

Get a deep section up front (a tri-spoke 2nd hand of e-bay is the best bang per buck) and an aero rear later if you can afford it. numbers wise, changing from a Kysirium front to a Zipp 808 front (arguably the most aero non-disk) will save you just under 90 secs over 25 miles. A disk rear will probably save you roughly another 30-40 secs.

A TT lid is good, but make sure you're using it properly; an aero lid with the tail sticking up can have higher drag than a regular helmet. Ideally, the tail should be flat against your back. TT lids should be tight and ideally, add as little frontal area to you as possible. Also, tape up the vents and you'll go faster.

A skinsuit will give a small improvement, so it's worth doing at some point. The same can be said of overshoes.

Conclusion
What Blah said

Longer conclusion
If you're going to end up with a full TT bike at some point, start off with a TT frame and bars to get used to outputting power in the correct position. I'd also add a helmet so that you can get used to the neck cranked back position. Use it over the winter on the turbo. Deal with wheels, skinsuits, overshoes etc, later. This is because they will not affect your power or anything about your riding style, just reduce overall drag.