Forum home Road cycling forum Amateur race

TT Bikes Performance Advantage

mab_bakermab_baker Posts: 45
edited July 2009 in Amateur race
I have just started having a go at time trials with a local club that runs a weekly 10 mile TT. I currently ride a mid range Specialised road bike with clip on tri bars, but 95% of the people that turn out have nice looking carbon TT bikes. My best time for the course is 24.23 and I'm wondering how much faster I'd be able to go with a carbon TT bike with a decent set of wheels. One other rider mentioned just having a decent set of wheels could save as much as 30secs on a 10 mile TT. Does that sound feasible and if so how much could I expect to shave off my TT time with a decent TT setup.

Posts

  • BeaconRuthBeaconRuth Posts: 2,086
    Briefly, I would say that in order of priority you should consider

    1) riding position
    2) wheels
    3) helmet and skinsuit etc
    4) frame

    but of course getting a TT frame might help you with 1). If I rode a 10-mile TT on a road bike with clip-on tribars and ordinary wheels in a non-ideal position I suspect I would be slower by at least 90 seconds, but possibly as much as 2 minutes. (Wild guesses.)

    Ruth
  • SBezzaSBezza Posts: 2,173
    One of the young lads from our club went about 90 secs quicker when he got his TT bike, compared with just riding his road bike. Conditions would have been different between the 2 days however, so it might not be so big a difference.

    I went about 1 min quicker when I used my TT bike in comparison to a road bike with clip ons, so I would say 1 to 2 mins depending weather and the like.

    Plus you don't need a shiny carbon TT bike, I have a second hand TCR Aero frame, with mainly secondhand parts on it, and I go faster than those with £5k+ bikes. It is the person doing the pedalling that can make the greatest difference IMO, though a nice TT bike does look the business.
  • ride_wheneverride_whenever Posts: 13,279
    i think the thing to consider first is the engine!!!!!!

    mileage make champions.
  • mab_bakermab_baker Posts: 45
    Thanks guys, I totally appreciate that the engine is the most important thing and the person on the bike is the biggest cause of drag. I was just curious how close I could get to the fastest guys competing on similar kit to them, albeit with the existing engine.

    SBezza, I notice you are from the Maidstone area. Which TT's do you enter? I'm not far from you in Kent. I currently do the Weds night 10 miler that Bexley Cycle Club run up along the A20 by Brands Hatch, but am keen to try other events.
  • SBezzaSBezza Posts: 2,173
    mab_baker wrote:
    Thanks guys, I totally appreciate that the engine is the most important thing and the person on the bike is the biggest cause of drag. I was just curious how close I could get to the fastest guys competing on similar kit to them, albeit with the existing engine.

    SBezza, I notice you are from the Maidstone area. Which TT's do you enter? I'm not far from you in Kent. I currently do the Weds night 10 miler that Bexley Cycle Club run up along the A20 by Brands Hatch, but am keen to try other events.

    Try not to get hung up on how close you get to the other guys, though taking an interest is good. Most of the fast guys will have been doing it for a few years, and have them years of training as well to improve themselves.

    I enter my club events (San Fairy Ann CC) which is on the A20 at Harrietsham on Wednesday nights, I think it is £2 if you have not signed up for the season. Though next Wednesday we are on another course, though not sure if Wigmore will still be on the A20.

    I also enter open events, mainly Kent ones, though I have entered events in Hampshire and Essex, as the courses are faster. I might have to try the Bexley 10's one evening to see what the course is like up there.
  • RChungRChung Posts: 163
    mab_baker wrote:
    how much could I expect to shave off my TT time with a decent TT setup.
    More than this amount:
    http://forum.slowtwitch.com/cgi-bin/gforum.cgi?post=1802183
  • ride_wheneverride_whenever Posts: 13,279
    SBezza wrote:
    Try not to get hung up on how close you get to the other guys, though taking an interest is good.

    That's some very good advice. When you're training for competition, you can sort every possible aspect of your ability. You can be the fastest that you can, however the one thing that you have absolutely no control over is how fast the competitors go. At the end of the day, if I raced (I don't but it is by the by), I'd rather put in a great performance for me and come last than win and feel I could have gone faster.
  • RChung wrote:
    mab_baker wrote:
    how much could I expect to shave off my TT time with a decent TT setup.
    More than this amount:
    http://forum.slowtwitch.com/cgi-bin/gforum.cgi?post=1802183
    Radar Chung.... :)
    Slow elsewhere?
  • RChungRChung Posts: 163
    Slow elsewhere?
    Just diversifying the portfolio.
  • RChung wrote:
    Slow elsewhere?
    Just diversifying the portfolio.
    It can be fun playing in a new sandbox.
  • a_n_ta_n_t Posts: 2,011
    RChung wrote:


    erm, so is that a yes or no? :?
    Manchester wheelers

    PB's
    10m 20:21 2014
    25m 53:18 20:13
    50m 1:57:12 2013
    100m Yeah right.
  • RChungRChung Posts: 163
    It can be fun playing in a new sandbox.
    Only until you discover the neighborhood cat beat you to it. Maybe "fishing in a new spot" is better, especially if your lines are drawn through the water.
  • RChungRChung Posts: 163
    a_n_t wrote:
    RChung wrote:
    erm, so is that a yes or no? :?
    The OP wanted to know "how much could I expect to shave off my TT time with a decent TT setup". That link pointed to a test where position was held constant, wheels were held constant, clothing and helmet were held constant, and only a frame was swapped out -- and the measured difference was equivalent to about 2 sec/km. Even ignoring the power production side of the equation, substantial improvements on the drag side can be made, not only through aero improvements but also rolling resistance reduction. We don't know (and probably, he doesn't either) his actual drag characteristics but if he's a "typical" beginning racer using "typical" equipment in a "typical" road-bike-with-clip-on position, he could be looking at up to 10 secs/km.
  • a_n_ta_n_t Posts: 2,011
    RChung wrote:
    about 2 sec/km.

    thats all you had to say :lol:

    Pages of numbers/graphs hold my attention for less than the time gains / km!
    Manchester wheelers

    PB's
    10m 20:21 2014
    25m 53:18 20:13
    50m 1:57:12 2013
    100m Yeah right.
  • RChungRChung Posts: 163
    a_n_t wrote:
    RChung wrote:
    about 2 sec/km.
    thats all you had to say :lol:

    Pages of numbers/graphs hold my attention for less than the time gains / km!
    Should've taken another second to read the rest of the paragraph: that was 2 secs/km for a single component. Up to 10 sec/km for other pieces.
  • ChrisszChrissz Posts: 727
    No scientific evidence but....................................

    Years ago when I used to play TTs a mate and I had a similar question. We were both hitting very similar times on the club 10 and decided to see how much difference TT bike + head faring vs 'normal' bike made to our times so, for 4 weeks we alternated between our TT bikes and normal road bikes (all on the same course). We were both around 45 seconds slower on the normal set ups for the same 10 mile course.

    As I stated - not scientific but.............................................................
  • sub55sub55 Posts: 1,025
    Chrissz wrote:
    No scientific evidence but....................................

    Years ago when I used to play TTs a mate and I had a similar question. We were both hitting very similar times on the club 10 and decided to see how much difference TT bike + head faring vs 'normal' bike made to our times so, for 4 weeks we alternated between our TT bikes and normal road bikes (all on the same course). We were both around 45 seconds slower on the normal set ups for the same 10 mile course.

    As I stated - not scientific but.............................................................

    i rekon its the same amount, 45 secs. for me
    funny thing is ,those who dont have full tt bikes, seem to think its several mins. those who do, soon realise that its not more than a handful of secs.

    anybody who suggests to you a time differential in terms of time, does`nt know what they are talking about. it can only be described as a %.
    constantly reavalueating the situation and altering the perceived parameters accordingly
  • Here is a detailed breakdown of the difference between a road bike and TT bike on the same course, taking into consideration differences in the the environmental conditions, power output, aerodynamics and pacing:
    http://alex-cycle.blogspot.com/2009/04/new-skool.html

    The aerodynamic changes made were worth 4 seconds/km in my case.
  • RChungRChung Posts: 163
    The aerodynamic changes made were worth 4 seconds/km in my case.
    The slower you are the more you benefit from aero improvements.
  • RChung wrote:
    It can be fun playing in a new sandbox.
    Only until you discover the neighborhood cat beat you to it. Maybe "fishing in a new spot" is better, especially if your lines are drawn through the water.
    He he - well I'm sure you are going to get a few Herrings nibbling away....
  • RChung wrote:
    The aerodynamic changes made were worth 4 seconds/km in my case.
    The slower you are the more you benefit from aero improvements.
    Not one nibble on this statement.

    Maybe my work here is done.
  • John.TJohn.T Posts: 3,698
    RChung wrote:
    The aerodynamic changes made were worth 4 seconds/km in my case.
    The slower you are the more you benefit from aero improvements.
    Not one nibble on this statement.

    Maybe my work here is done.
    :roll:
  • RChungRChung Posts: 163
    Not one nibble on this statement.

    Maybe my work here is done.
    Maybe they're hard of herring. If we wait long enough salmon'll take a bite.
  • Simon NotleySimon Notley Posts: 1,263
    To answer the question. My observations of other riders during our evening TTs suggests that a TT bike might be worth as much as 5 minutes over 25 miles or 2 minutes over 10 compared to a standard road bike with no aerobars , but that is obviously a gross generalisation and will depend on all kinds of things.
  • nick hansonnick hanson Posts: 1,655
    Going back quite a few years,one of my club's top TT'ers went 'aero'
    (tri bars on his low pro,disc back wheel aero helmet) & lowered his PB
    (& my club record)
    He said he did the improvement purely due to the equipment,& reconed the gear shaved a good 1 1/2 to 2 mins off his 25 time.
    Still,a damn good ride (a low 53,i think)
    so,going off this for a 10,about 30 to 45 seconds should do it!
    so many cols,so little time!
Sign In or Register to comment.