Sizing The Frame Question: What's The Right Size For Me ?

Discussion in 'Beginners Forum' started by Robert11, Apr 16, 2011.

  1. Robert11

    Robert11 New Member


    Sr. Citizen contemplating taking up lite biking again.
    Considering a Marin Redwood, or one of the Specialized Bike brands
    Hybrids. About an even split between riding on asphalt and light dirt/gravel.

    I realize that ultimately it's how the bike feels and rides for you, but a 10 minute test drive really doesn't do it for a good evaluation.

    Also, that I'm not smart enough to really judge the right size for me very accurately. Have ridden 17" thru 20" sizes that "seem" comfortable.

    Also, the Specialized brand, they tell me, only comes in small, medium, large, and X-Large. I tried a Large, and it seemed pretty good.

    The impression I get from the Salesmen in the stores is that they really want to get rid of the size(s) they happen to have in stock.
    Also, none of them really seem all that knowledgeable re sizing.

    So, a very basic, generic, question, please:

    I'm 5'11" and weigh 170.

    What would be the right frame size for me, "most likely" ?
    (should I also be asking about tire size ?)

    BTW: All the seats seemed horrible, probably to a large extent, that I'm not used to them. Is there any agreement on which brand/model seat is the most comfortable for a true recreational rider.
    Maybe I could get them to swap it out.

  2. retromike3

    retromike3 retromike3

    a question of fit

    There is a formula that used to work for sizing people to bikes, but it has been a while since its been effect. Generally If you stand over a bike and pull up on the handle bar it used to be that you should have about two inches of space between you and the top tube. Now bikes have a much lower top tube so I guess it would be more like four inches on a modern mountain bike.

    Something you might not have thought of is the with of your handle bars and the length of your frame and stem. Generally when your on the bike the handle bar should cover the axle of the front hub when you look down. The only way I could get a frame that would fit me was to build my own. I have short legs and a long torso so it makes a funny looking bike.

    As for saddles it may be said that the only true hard asses in sports are cyclists. I think that you need to get a firm saddle because a big soft one will get in the way and rub you wrong.Classic position is absolutely flat, parallel to the ground. Its gong to hurt to start with but it will get better the more you ride because you will be using mussels that have not been used in that way and they will be upset about it for awhile. If you local bike shop has a Fit Kit its worth getting set up or just find some old shop guy to set you up.


  3. chibibike

    chibibike Banned

    you'd prolly need a 20 or 21 inch. if you have more than a 32in inseam then deffinately bigger than a 19in.
  4. SprocketGirl

    SprocketGirl spin... spin.. spin

    toptube in my opinion is the key to fit. while seatpost matters i have found a toptube length is the most important aspect.

    check out competitive cyclist they have a cool fit calculator but it only gets you so close.
  5. flyingdog

    flyingdog Member

    Pretty straight forward explanation of why you do what you do.

    How to fit a bicycle

    The best advice is in their conclusion:

    Ultimately, no one else can fit you to your bike. You must first listen to the feedback your body is sending and become familiar with its language.
  6. wild

    wild Yesterday tired old man, Today retired old man

    I must say I think the top tube is the key to a good fit. If the top tube is to long you will be stretched out to short and you will be scrunched up, neather will be comfy on a long ride. Yes you can change the stem, but you can only do so much with it befor it changes the steering geom. Of corse you must have some stand over clerance, but that can be from all most tutching to plenty. allso if the top tube is not right it may be hard too get that knee over pedal where it is neaded. I would think a 17 or 19 would be in the ball park, but diferent style frames fit different, I have a 17 over hear that is biger than one of my 19s .
    Good read flyingdog
    My .02
    Last edited: Apr 19, 2011