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New Bike. Right Size? Gear Issues?

jimishepjimishep Posts: 37
edited April 2016 in MTB beginners

I've finally bought my new bike after much deliberation over the past month or so opting for a Medium - 17".

I'm 5 foot 9 and a bit. For some reason I feel a little cramped on the bike albeit there's no way I would've been able to reach the floor on a 19". With the seat as far down as it can go I can just comfortably stand on the ball of my feet. I had to order by mail order. I've also got some issues changing gears. When switching between the front cogs the chain sometimes fails to catch on the required cog. You have to really push the shifters to force the move. Any ideas?



  • JBAJBA Posts: 2,842
    Why do you want to put your feet flat on the floor when you are sat on the bike? If you can do that your saddle is too low.

    You should have the saddle at the correct height for efficient pedalling. Have a look HERE. The guide is for a road bike but it's the same for an MTB.

    WRT the gear change it probably needs adjusting. Look at Parktools for some good teaching videos.
    “Life has been unfaithful
    And it all promised so so much”

    Giant Trance 2 27.5 2016 ¦ Sonder Broken Road 2021¦ Giant Revolt Advanced 2 2019 ¦ Giant Toughtroad SLR 1 2019 ¦ Giant Anthem 3 2015 ¦ Specialized Myka Comp FSR 2009
  • jimishepjimishep Posts: 37
    Thanks! I'll check out the videos regarding the gear changes or maybe pop it down to my LBS.

    Regarding the size, is it better to have a smaller frame with a higher saddle or a bigger frame with a low saddle? I'm confused as both could achieve the desired 'fit'.
  • rockmonkeyscrockmonkeysc Posts: 14,774
    The most important thing in bike sizing is the length of the bike. You don't want to be cramped or stretched out.
  • The RookieThe Rookie Posts: 27,792
    All that matters is the relationship between the three contact points, pedals, grips and saddle, where the ground is reflects how a bike rides but not whether it fits or not.

    The nominal size is the length of the frame's seat tube but that is the least relevant to whether a bike fits which is the cockpit length from saddle to grips, that is only adjustable over a small range by sliding the saddle in the clamp, rotating the bars a small amount, you can change a seatpost (between frame and saddle) from inline to setback or vice versa but that doesn't always help.

    It's normal to have about 6" of seatpost showing between frame and saddle.
    Current steed - Whyte T129, 2013 frame, mongrel Revelations, Giant dropper, Stans S1 wheelset. 12, Magura Trail Sport brakes, 1x11. 12.8Kg
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