Difference between road bike and time trial bike

Last Sunday, I was out on my winter training hack. I averaged 16.8 mph for 70 miles and that was by sitting on Baines’ wheel for most of the ride  Yesterday I went out on time trial bike (with non-aero helmet and wheels) and averaged 21mph for 50 miles over similar terrain. In an incredibly unscientific method of deduction, that’s about 4mph faster on time trial bike.  It’s probably not quite that much. My legs felt better yesterday, and there was a little less climbing. But, as a rule of thumb, if you go from a road bike to good time trial set up, you should be able to go 1-3 mph for the same power effort.

It depends on many variables. My summer road bike stripped down is a good 1-2 mph faster than a winter training bike with mudguards, creaking gears and heavy road tyres. Maybe there is a psychological benefit that when you get on a time trial bike, which makes you want to pedal faster.

How much faster is a TT bike?

One of the great debates in cycling is how much faster would an old school time-triallist like Alf Engers have gone on a full time trial bike with dischwheel e.t.c? It’s impossible to say. Some of the 1970s time triallists had their position down to a fine art. It was only really the arm positions which could have been improved on with tribars. Though discwheels and skinsuits would add quite a bit too.  In 1978 Alf Engers did a 49.24 for a 25 mile time trial ( 30.3mph / 48.8g km/h). That was before TT bikes, aerobars, discwheels and aero-helmets – to say nothing of wind tunnels and modern nutrition methods.

The current 25 mile time trial record is 45-46, set by Michael Hutchinson in 2012. (32.5mph / 52.7 km/h) – nearly 4km/h faster

alf-engers

Alf Engers in TT mode. The main benefit of a modern TT set up would have been moving his arms out of the wind-flow.

UCI athlete hour record and UCI Ultimate record

boardman

One interesting comparison is Chris Boardman’s hour records. Boardman set hour records of 52.270km and later 56.375 km. This 56.3km stands as the ultimate hour record – using an extreme ‘superman’ position – Boardman was literally flying through the air.

Then the UCI changed the rules so basically you had to use 1970s equipment. In 2000, Boardman just beat Merckx to set a new athlete’s hour record of 49.441 km

That suggests a 7km/h difference between the fastest time-trial position and an ordinary road bike.

In practise, the superman position has been banned from most competitions. The average time trial position is somewhere between the Superman and road bike.

nick-english-10mileTT-aw-cycles

Disadvantages of time trial bike v road bike

  • Heavier. A time trial bike is typically 1-2kg heavier than a road bike. This is because the main focus is making a time trial bike more aerodynamic rather than lightweight. TT frames tend to be heavier because of bigger ‘aerofoils’ and bigger frames. This can put a time trial bike at a disadvantage going up hill. Tribars are also heavier than a simpler road bike handlebar.
  • Handling. If a time trial bike is faster why don’t people use it in road stages? The UCI have disallowed it because simply they are more difficult to handle (plus the UCI dislike the aesthetics of TT bikes). TT bikes are a bit heavier in their handling. This is due to the geometry of the frame, but also because the handlebars are different. It is harder to make fine adjustments on narrow tribars. This is not a problem when doing a solo time trial, but it would be a big problem in a busy peleton with people fighting for position.
  • Different position uses different muscles. The set up on a time trial bike, puts you in a different position. Becoming more aerodynamic can lead to a loss of power. This is especially a problem if you don’t train in the time trial position and get used to the position. It means road riders who do a time trial in a grand stage, may struggle if they haven’t practised for many hours on a time trial bike.
  • Discomfort. A time trial bike lends itself to a more aerodynamic / uncomfortable position. You place a lot of pressure on your bike, shoulders, neck, groin. If you’re not used to it, it can be torture; even if you are used to it, it still ends up being painful. When Fabian Cancellara was asked what is most difficult training session was – he immediately replied a six hour ride on the TT bike. This is a good reason why ‘touring cyclists’ would not choose aerodynamics. It’s more important to be free of pain and enjoy the ride.
  • Anti-social I guess one of the main drawbacks of TT bikes is that they are antisocial. Don’t turn up on a group ride on a TT bike.

Is a road bike ever quicker for a hilly time trial?

  • Many people assume that for a very hilly time trial, you might be better off on a road bike because the weight saving and better handling outweigh the aerodynamics. As a general rule, the aero benefits of a time trial bike will always trump the weight saving and handling on any hill time trial. Road bikes are just slower, even on very hilly course. It would have to be a ridiculously hilly time trial for a road bike to be better. Perhaps really severe climbs and descents so you are hardly pedalling on the descent. Perhaps the Bristol CC hilly time trial around Dursley with a course record of around 20mph might fit the bill. But, if if in doubt use the time trial bike if you want to go faster.
  • Hill climbs. It seems counter-intuitive. But, there are even hill climbs where a time trial bike is quicker than a road bike. If the gradient is 4% or less, the aero benefits can outweigh the weight saving. If there is a headwind up the climb, the benefit of an aero bike is even more pronounced.

So why don’t more people ride TT bikes?

When I get on a time trial bike, I get a real buzz from the speed. That’s one of the attractions of cycling – self-propelled speed. It is uncomfortable, but the more you ride it, the more used to the position you get. But, unless you are doing time trials, most people are reluctant to spend money on a bike they won’t use very regularly. I like both the road bike and the time trial bike. For a ride around the hills of Yorkshire and the Lake District I would choose a road bike. But, I also like the time trial bike sessions in a different way.

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19 Responses to Difference between road bike and time trial bike

  1. Human Cyclist February 5, 2014 at 8:24 pm #

    I’m always slightly envious when a timetrial bike comes flying past me. I love the hum they make too, great sound, must add to that feeling of flying. I shall no longer be so downhearted when overtaken by a TT bike. Of course I shall be extra elated to overtake somebody on a TT bike (always a pleasure!).

    • tejvan February 5, 2014 at 10:34 pm #

      Yes, actually the noise of a disc wheel in full flight I quite like.

  2. tejvan February 5, 2014 at 10:38 pm #

    Watching the Tour of Dubai on telly, and they were doing a time trial on road bikes!

    Taylor Phinney won flat 9.9 km TT in 12.03 Average speed 30.6mph, 49km/h

  3. Simon Noble February 2, 2015 at 3:06 pm #

    Hello Trejvan,

    I like your advice and the way you explained the options and your web page..

    I have been using a 2002 Eddy Merckx Alu Sprint, drop-bar road bike, since that purchase date. This road bike has a fairly orthodox design: horizontal top tube and ovalized downtube; fabricated in aluminium with a carbon fork. I put a review onto the Internet.

    I have a similar performance to yourself: 16.7mph over the return trip of 100 miles from Gosport, Hampshire, to Chiddingford, Surrey and back, over moderately hilly but fast country roads (old A3).

    I have been watching Cervelo and Eddy Merckx products since 2002 and the trends in geometries were never to my liking; the Cervelo P-series were too low and extended; the Cervelo S-series bikes were moving to even higher stack heights and shorter reaches; Eddy Merckx geometries remained conservative.

    I would like to extend lower and further forwards. I fit the EM 52cm frame perfectly but I am always on the hoods or drops with the handlebar spacers only 5mm. My quadracepts do take a punishing, with cramps a feature on hills, so moving to a forward position would be relaxing and I have the flexibility to achieve that.

    For 2015, Cervelo have increased the stack height and reduced the reach for their P2, P3 and P5 machines; Eddy Merckx has extended the reach for the San Remo 76.

    At last I can ask the pertinant question: Are the Cervelo P2, P3 and P5 machines a viable option for running in drop-bar configuration? Would these machines be viable as general purpose road machines to supplement the Eddy Merckx style of machine, at teast for dry summer road use, for rides in moderate hilly (<5% gradients) country, and over flat terrain.

    I habitually do PBs. It's early-days…….have you a view on the matter? I've requested a registration on the Cervelo forum and am currently waiting for approval.

    King regards from Simon (FastEddy)

    • tejvan February 2, 2015 at 7:10 pm #

      Hi Simon,

      I’m afraid, I don’t have much idea about Cervelo’s. Enjoy your pb’s!

  4. Seb September 16, 2015 at 6:09 pm #

    Hi Tejvan,

    I have done a season of 10’s and really enjoyed it and I am gonna have a good crack at a load more TTs next season.

    At the moment I use a carbon road bike with clip on aero bars, however I aim to replace the handle bars/clip ons with a full TT aero bar setup next year as well as my aero wheels (80mm), skinsuit and aero helmet.

    Will the road frame work well as a TT setup or is a TT specific frame going to make a massive difference?

    Cheers

    • tejvan September 17, 2015 at 8:11 am #

      TT specific frame and good position will definitely help speed even more than road bike with clip-ons

  5. Dan November 22, 2015 at 11:41 pm #

    It’s all about money. The industry probably wants to keep weekend warriors hooked into the high-end professional bike image and spending top dollar to reduce every gram on those, see point 1. If that image strays too far from weekend physique reality, then they’ll give up. Once they’re buying entirely different bikes than the pros anyway then they will no longer fork out a couple of thousand extra to make it more pro-like. If pros go to TT bikes, the weekend warriors will be forced to accept their position on amateur road bikes. They’ll also realize that every gram really does not matter.

  6. jordan January 22, 2016 at 10:46 pm #

    Built a steed of dual road and TT ride affordably using this strategy. Keeps angles proper in both positions.

    http://www.jordanpfowler.com/2016/01/11/bike-setup-12-hour-time-trial/

  7. RGRHON January 22, 2017 at 12:10 pm #

    The weight of a TT bike would be unnecessary in a road race. First, aero is less important in a peloton. Only the leaders need to be particularly aero. Second, the distances are typically but not always longer, and comfort translates to less fatigue and faster times when riding in a group. You also don’t sprint as well on a TT bike. The handling of a TT bike is too poor for maneuvering in a peloton. And lastly, a 4% grade wouldn’t be considered a hill in a road race. Hills in road races typically vary from 10-20% grade. It’s harder to climb big hills like that in a TT configuration. Each type of bike is made for it’s niche. While some riders would undoubtedly use a TT bike on flat stages if they could, as a bicycle for varied terrain, the road bike wins.

    • Gordon Ballon April 28, 2017 at 1:43 pm #

      Good response. There is a distance where a TT has an advantage and where it loses it which is somewhat dependent on the cyclist. The question is what is this range? And, why do some think a TT fatigues the legs less for running than a road bike when the foot, knee, hip alignment is the same?

  8. jamm cyclist April 21, 2017 at 3:46 pm #

    If a TT is consistently faster, why do Tour riders not use them in all or most stages as they can use a TT or Road or most any model they want that meets the rules.

    • tejvan April 23, 2017 at 9:03 am #

      TT bikes are not allowed in normal stages (not even clip on bars) It would make the racing more dangerous as TT bikes are harder to control in bunch.

      • Gordon Ballon April 28, 2017 at 1:45 pm #

        Tejvan that is correct, however, there is a distance at which a road bike is better on the body than a TT and how this affects the run. Seems the longer the ride, the more the road bike is better for the ride due to less fatigue from being cramped and this enables the run stage to be faster.

  9. CS July 31, 2017 at 3:45 am #

    Tejvan, do you know if a TT bike handlebars can be modified to a drop-down?

    • tejvan August 2, 2017 at 2:27 pm #

      I don’t think so.

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