bouncing bike

skijohnsonr
skijohnsonr Posts: 4
edited December 2012 in Road general
Hi,can someone help.I had a problem with my bike(trek madone 3.1 2011)bouncing when i was following a friend up a long hill,i am 85kg and am quite powerfull.i am not sure if the crank(sram apex)is a bit budget and was flexing or it was the frame or a combo of the two.my friend has a high end superbike and he did not have the problem?

Comments

  • Gizmodo
    Gizmodo Posts: 1,928
    The only time I've felt like I'm "bouncing" on my Trek Madone 3.5 is when I had a slow puncture and the rear pressure was down to like 50psi. Each time I pushed on the pedal it felt like the bike was almost leaving the ground. Check your tire pressures.

    To work out your tire pressures http://www.bikequarterly.com/images/TireDrop.pdf
  • navrig
    navrig Posts: 1,352
    Although unlikely to be the cause, check your frame for cracks.
  • Bulge in the tyre ? makes you bob up and down :)
  • Bozman
    Bozman Posts: 2,518
    Poor fitting tyre? Spin the wheel and check that it spins true or.... pedaling technique, when you're spinning at a high cadence you could be bouncing.
  • cougie
    cougie Posts: 22,512
    I doubt you're flexing anything. My guess is a soft tyre or your technique is wrong ? Too low a gear ?
  • thefd
    thefd Posts: 1,021
    Unlikely but....What was your cadence like? Sometimes if it is too high you can feel like you are bouncing.
    2017 - Caadx
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  • Monty Dog
    Monty Dog Posts: 20,614
    Lean over the back of the bike and press down firmly on the saddle looking down to see if anything's moving that shouldn't
    Make mine an Italian, with Campagnolo on the side..
  • jameses
    jameses Posts: 653
    Gizmodo wrote:
    The only time I've felt like I'm "bouncing" on my Trek Madone 3.5 is when I had a slow puncture and the rear pressure was down to like 50psi. Each time I pushed on the pedal it felt like the bike was almost leaving the ground. Check your tire pressures.

    To work out your tire pressures http://www.bikequarterly.com/images/TireDrop.pdf

    +1
    Went out a few weeks back after changing to my winter wheels and was really struggling up a climb with a feeling of bouncing about an hour into the ride. Stopped and checked my tyre at the top and found it to be nigh on flat.
  • declan1
    declan1 Posts: 2,470
    When sprinting I unintentionally lift up my front wheel every pedal stroke. That is riding a very heavy steel bike. I could imagine it's quite easy to do on a light carbon frame.

    Road - Dolan Preffisio
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    I have no idea what's going on here.
  • jameses
    jameses Posts: 653
    declan1 wrote:
    When sprinting I unintentionally lift up my front wheel every pedal stroke. That is riding a very heavy steel bike. I could imagine it's quite easy to do on a light carbon frame.

    Lean forward and put more weight over the front? The bouncing I felt was from the rear of the bike (where the puncture was) not the front, and less obvious than when a wheel is lifting.
  • Ok I am begining to think my cadence was to high as I always check tyre pressure.I was in my lowest gear trying to not get dropped.my cadence was well over 100 when it started and it really sapped all my remaining energy
  • May well have been cadence. I tried some high cadence drills on the rollers a while ago. once I got above about 125 the bike was all over the place! I obviously have some work to do on my high speed pedalling technique!
  • thanks guys,i think the problem is solved,though i think i will upgrade the crank as it seems a budget item to me,any ideas i was thinking of a rotor ring
  • dennisn
    dennisn Posts: 10,601
    thanks guys,i think the problem is solved,though i think i will upgrade the crank as it seems a budget item to me,any ideas i was thinking of a rotor ring

    I'm thinking that you won't solve this problem by buying new stuff. I can buy into the cadence thing causing a bit of bouncing and the low tire idea, but a crankset causing this? No. I suppose that IF(big if) the bottom bracket is loose that it might feel somewhat strange. I would say that you shouldn't buy anything until you've proven to yourself that what you're buying IS the cause of your problems(whatever they may be).
  • Herbsman
    Herbsman Posts: 2,029
    Have you tried pedaling less hard?
    CAPTAIN BUCKFAST'S CYCLING TIPS - GUARANTEED TO WORK! 1 OUT OF 10 RACING CYCLISTS AGREE!
  • mouth
    mouth Posts: 1,195
    I experienced something similar recently and it turned out that the qr skewer was about half a turn too loose in the front wheel. Bloody glad it didn't let go.
    The only disability in life is a poor attitude.
  • cougie
    cougie Posts: 22,512
    It's not the crank. All you're doing there is lightening your wallet. It won't solve the problem.