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  1. #1
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    Trek 7.2 fx and speed

    I recently just switched from a Specialized Allez Triple Sport to a trek 7.2 fx 2010. I've found im easily able to go the same speed (18mph or so) on average when theres no wind (and my higher speeds match the Allez's when there is a tail wind), However, when going against the wind my average speed drops by about 2-3mph compared to the allez (sometimes dropping to 11mph). Is this just a side effect of being a flat bar or is there something I can do it about it? Everything so far is stock besides rack and lights (same exact ones as my allez as well so i doubt these are causing the issues)

    I was debating among one of three things, or possibly a combination

    1) adding these to my bike in the middle
    http://www.amazon.com/gp/product/B00...A2TE9IQP68MWQU
    very much how this person did http://i14.photobucket.com/albums/a3...r/DSC03080.jpg (saved this image from the forums, forget whose it is, sorry about that)

    2)adding these somewhat in the middle so they simulate drop bars
    http://www.amazon.com/Origin-Bicycle...7308366&sr=1-5

    3) getting a pair of triathlon clip-on's somewhat similar to this one
    http://www.amazon.com/gp/product/B00...sr=1-3&seller=


    I find i like the more upright position of the trek 7.2fx and the wider handlebars when riding compared to drops, which is why i made the switch. But riding against the wind is almost intolerable so any suggestions would greatly be appreciated.

  2. #2
    aka Phil Jungels Wanderer's Avatar
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    The Origin 8 mini drops, bolt on, and work passably well.

    "Retirement is the best job I ever had!" Me, 2009


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  3. #3
    Senior Member KungPaoSchwinn's Avatar
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    Matt, i checked your Allez and it's a road bike,don't you think that's enough to make the different in speed?
    2009 Trek FX 7.3

  4. #4
    triple chainring club
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    bar ends on the inside of the grips is intriguing.. that should keep your arms closer together; less of the "sail" effect that a regular flat-bar position creates.. but you'll still be fairly upright and catching alot of wind though. the clip-ons in option #3 will probably provide the best aero position.

  5. #5
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    Quote Originally Posted by KungPaoSchwinn View Post
    Matt, i checked your Allez and it's a road bike,don't you think that's enough to make the different in speed?
    My old bike: http://www.bikepedia.com/QuickBike/B...1806&Type=bike

    I originally though switching would create a significant distance in speed, but on flats (I never took my allez up any hills, ride in a flat area) as well as with a tailwind my speed has remained exactly the same based on what my cyclocomputer says (i changed the wheel size too to match the thicker tires of the 7.2 fx which takes 700x35 so i doubt its my cyclocomputer misreading).

    I figured the difference in speed from the headwind is from the "sail" effect and was wondering if anyone knew the best way to combat that. I doubt just the handlebars sticking out would cause to much of a difference so i was thinking the tri-athlon bars or origin8 bars would help.

  6. #6
    Senior Member AdelaaR's Avatar
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    I have a flatbar with triathlon aerobars and I can assure you it is wonderfull
    They aren't cheap though for sturdy ones and there are a whole lot of different types outthere so choose wisely, since most of them are made for triathlon-geometry bikes and will be too long for normal hybrids.
    Take a look at the picture-thread on pages 45-46 ... I posted some pictures there of my set-up. The effect of the tri-bars was immediately noticeable when going against the wind or downhill.

  7. #7
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    Quote Originally Posted by AdelaaR View Post
    I have a flatbar with triathlon aerobars and I can assure you it is wonderfull
    They aren't cheap though for sturdy ones and there are a whole lot of different types outthere so choose wisely, since most of them are made for triathlon-geometry bikes and will be too long for normal hybrids.
    Take a look at the picture-thread on pages 45-46 ... I posted some pictures there of my set-up. The effect of the tri-bars was immediately noticeable when going against the wind or downhill.
    Glad to hear that. I'll probably pick up the tri-athlon bars first and if they do the job forget about the other two. Thanks for letting me know and hopefully I'll be back up to speed when in a headwind.

  8. #8
    LBS Employee/Commuter
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    I can't get the picture to upload, but here's the link to a picture of mine: http://twitpic.com/1ha3fz

    In a similar fashion to the bar ends mounted inward that you posted, I picked up some longer ones with a curve at the end. Puts my hands in a much more comfortable position that a straight bar end would have and then I also wrapped it with some extra padding for my arms. I tend not to actually rest my arms on the bars much, but when I do, it doesn't hurt. Headwinds still suck, but not nearly as much. I did a few rides with it before taping the bars to dial in position.

    Sidenote: if you do this, start the wrapping at the tips of the barends then finish on the main handlebar. I need to swap mine around to do this. Unravels a little to easy in hot weather combined with pressure near the electrical tape

  9. #9
    Senior Member AdelaaR's Avatar
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    Looks very original and cool, bjoerges

  10. #10
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    Decided to try the tri bar first, i'll post pictures once it gets in. Does anyone know if road slicks could also possibly increase my speed? The bike comes with 700 x 35c tires with slight treads and was wondering if the upgrade to thinner tires without treads would help (if its anything less than 1.5mph or so i'd prob stick with the current ones for comfort.)

    these are the tires that come with it:
    http://longbeachbicycleny.com/images...tr_h2_09_m.jpg

  11. #11
    Specialized Secteur Sport EDDIE1963's Avatar
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    I owned a 2010 Specialized Sirrus I purchased in March. I joined a Cycling club and found out quick I could not keep pace with Road bikes on long rides. I did install 700x25 tires and bar end to help with the numbness and it help. I sold the bike two week ago and purchased a road bike. The smaller tire will increase your speed. I love Hybrids and will purchase another in the future.

  12. #12
    Senior Member meanwhile's Avatar
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    Quote Originally Posted by KungPaoSchwinn View Post
    Matt, i checked your Allez and it's a road bike,don't you think that's enough to make the different in speed?
    Well, yes. But what is it about a road bike that you think it makes it slower under these circumstances..?

    Matt095 is right; it's air resistance caused by his body acting as a sail. To reduce it he'd need either drops, a long stem and narrower bars, or an aero bar. Aero bars will reduce drag most.

    Re the suggestion about 25mm tyres: on a smooth surface tyre drag is either rolling resistance, which all things being equal gets worse for narrower tyres, or air resistance. Tyre air resistance is marginal and not worth worrying about except for racing. Especially given the other disadvantages of narrow tyres.

  13. #13
    Senior Member AdelaaR's Avatar
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    Quote Originally Posted by meanwhile View Post
    tyre drag is either rolling resistance, which all things being equal gets worse for narrower tyres
    You are not seriously suggesting that rolling resistance is increased with narrower tyres, right?

  14. #14
    cs1
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    Hope that helps.

    1999 Waterford RSE-11, 1995 Waterford 1200, 1989 Specialized Rockhopper Comp
    1989 Raleigh Technium, 1989 Schwinn Traveler, 1986 Specialized Rockhopper
    1984 Specialized Stumpjumper, 1986 Specialized Stumpjumper and just way too many projects to list.

  15. #15
    Senior Member Terrierman's Avatar
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    Matt905:

    1) adding these to my bike in the middle
    http://www.amazon.com/gp/product/B00...A2TE9IQP68MWQU
    very much how this person did http://i14.photobucket.com/albums/a3...r/DSC03080.jpg (saved this image from the forums, forget whose it is, sorry about that)

    That's my bike. It's a Jamis Coda Elite, the bar is a crowbar that has a little more rise and offset than the stock bar that came on the Coda. Glad you like it. It's still set up that way and I'm still very happy with it. I mainly did it for comfort and more hand positions, but as you say it's a little more aero. I had to put the left bar end on the right side and vice versa to get the angles how I wanted them. Finishing the bar tape under the grips keeps it in place trouble free.

    Good luck.
    Last edited by Terrierman; 06-29-10 at 08:00 AM.
    It's all downhill from here. Except the parts that are uphill.

  16. #16
    Senior Member Terrierman's Avatar
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    Quote Originally Posted by Matt905 View Post
    Decided to try the tri bar first, i'll post pictures once it gets in. Does anyone know if road slicks could also possibly increase my speed? The bike comes with 700 x 35c tires with slight treads and was wondering if the upgrade to thinner tires without treads would help (if its anything less than 1.5mph or so i'd prob stick with the current ones for comfort.)

    these are the tires that come with it:
    http://longbeachbicycleny.com/images...tr_h2_09_m.jpg
    Go to 700 x 28 slicks for a good compromise. I run Continental Ultra Gator Skins and am happy with them.
    It's all downhill from here. Except the parts that are uphill.

  17. #17
    Senior Member meanwhile's Avatar
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    Quote Originally Posted by AdelaaR View Post
    You are not seriously suggesting that rolling resistance is increased with narrower tyres, right?
    If the tyres are otherwise identical, yes, the wider tyres will have lower RR. This is a surprise to people who don't read the technical info tyre makers provide because they have two misconceptions

    1. That RR is frictional (it's not - it's hysteresis energy, which is very different)

    2. That a narrower tyre will have a smaller contact patch than a wider tyre at the same pressure (wrong again - the narrower tyre will have a longer patch of the same area, which is less efficient for hysteresis energy.)

    Racers use narrow tyres because they give an aero advantage. To overcome the poor RR they have to pump them up super-high - this reduces contact patch size and so hysteresis energy losses. If you're not riding fast enough so that the very slight aero advantage of 25mm tyres outweighs the RR losses then wider tyres will actually be more efficient.

    Oh - and the high pressure strategy only works on smooth roads. Lower pressures become more efficient on rough stuff, but that's the advanced class.

    Good starter reference:

    http://www.rouesartisanales.over-blo...e-1503651.html

  18. #18
    Senior Member AdelaaR's Avatar
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    Ok, I have to admit you got me baffled here
    I was apparently misinformed that rolling resistance is frictional and thus is simply directly proportional to the tyre's contact patch size.
    I've never even heard of "hysteresis energy", but that could be because i'm not native english speakin' so i'll have to look it up one of these and check it out.
    Thanks for the info.

  19. #19
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    One of the reasons I've read that thinner tires work better is they support higher a PSI. However, at the same PSI wider tires do have less RR. I was just curious if this smaller tire would create that big a difference in speed, though for not it really doesn't matter as I can easily keep up with my friends, was wondering more for if i wanted to go on a group ride with the LBS and found I was too slow or just for solo rides.

    I'll probably keep my 700x35 tires and consider buying the 700x28 when these wear out

  20. #20
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    Quote Originally Posted by AdelaaR View Post
    Ok, I have to admit you got me baffled here
    I was apparently misinformed that rolling resistance is frictional and thus is simply directly proportional to the tyre's contact patch size.
    I've never even heard of "hysteresis energy", but that could be because i'm not native english speakin' so i'll have to look it up one of these and check it out.
    Thanks for the info.
    The hysteresis is the flexing of the tire's side walls where the tire balloons out a bit where it meets the ground-- This constant flexing of the tire as it rolls wastes energy. That is why inflating road bike tires to high pressures like 120 PSI helps reduce rolling resistance-- Less sidewall flexing in the tires.

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