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  1. #1
    Senior Member
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    Is it me or the tires ( or both)...

    I did not get any riding done this winter until march. Over the winter I
    gained 12 pounds.

    In late feb I took the bike ( Spec Sequoia Comp) in for a tune up and
    replaced the Specialized Pro (700x25)tires with Continental Grand Prix 4 Season (700x28)
    tires.

    I am running the new tires at 100psi.

    The ride is much more comfortable than the Specialized tires, but after about
    360 miles I cannot seem to produce the average cadence and speeds that I
    recorded last year.

    Most of the ugly hills I have to climb seem to require the bottom most gearing
    on my triple (30x28).

    Even going down hill feels a bit sluggish...There is one ultra steep downhill that
    I had to hit the brakes intermittently to hold the speed down to 45 mph.

    Now I just let it go and still only hit 45 mph.

    Are 28s that much slower than 25s?

    Should I be running a higher pressure ( the Specialized Pros I ran at 110 psi).

    I am currently running at about 210 lbs and will be 72 this summer...
    Perhaps my body is trying to tell me something.

    This will be my second year of biking

    Jerry

  2. #2
    Galveston County Texas 10 Wheels's Avatar
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    Your getting older.
    go slower.

    The only way I know would be to use two sets of wheels with the different tires on them.
    [SIZE=1][B]What I like about Texas[/B]
    http://www.youtube.com/watch?v=PGukLuXzH1E

    Set F1re To The Ra1n ( NY Night Rain Ride)
    http://www.youtube.com/watch?v=W7jfcWEkSrI

  3. #3
    Senior Member DieselDan's Avatar
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    Did you recalibrate your bike computer? You need to when you change tire size.
    Bikes use brakes to stop.

    If your bike has breaks, don't ride it.

  4. #4
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    Quote Originally Posted by DieselDan View Post
    Did you recalibrate your bike computer? You need to when you change tire size.
    yes i did...but in any case that should not affect my cadence...

    jerry

  5. #5
    Senior Member
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    Quote Originally Posted by yrrej View Post
    In late feb I took the bike ( Spec Sequoia Comp) in for a tune up and
    replaced the Specialized Pro (700x25)tires with Continental Grand Prix 4 Season (700x28)
    tires.

    I am running the new tires at 100psi.

    Should I be running a higher pressure ( the Specialized Pros I ran at 110 psi).
    I'm not sure but I think the bold sections explains it. Wider tires and lower pressure both come into play. Of course, for the hills and flats I would venture conditioning is the biggest issue (taking winter off), but for the downhill I think it's pressure and wind.

  6. #6
    Senior Member
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    You mentioned a tune up, is it possible that some wheel bearings have too much preload (too tight) because of the tuneup? Or maybe the wheel bearings need some attention.
    The tyranny of a multitude is a multiplied tyranny.

    When bad men combine, the good must associate; else they will fall one by one, an unpitied sacrifice in a contemptible struggle.

    - Edmund Burke

  7. #7
    Senior Member
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    Wider tires and lower pressure both come into play
    Kind of... for an identical tire those conditions will result in a higher rolling resistance but tread pattern and tire composition also have a major effect. IMO, 10psi and 3mm is too close to make any generalizations.

    Since you are seeing different behavior while coasting down a hill I would look at the tires or my riding position (air resistance).

  8. #8
    Senior Member adrien's Avatar
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    imho, Conti's are very tall tires...meaning for the same size, say 700x28s, the conti's tend to have the tread further away from the rim. Is it possible that is contributing to the issue?
    "how do you know you can't swim until you have drowned?"

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