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  1. #1
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    Motobecane 29 size

    When I ride a 26" bike, a 17" frame is too small for me, specifically, for my legs. I'm not able to extend as far as I'd like when the pedal is at the bottom, as a result knee stress.

    I assume I'd have the same problem with the moto 29 ?
    From
    http://motobecane.com/29geometry.html
    It seems that the length from the pedal to the seat for a 17" would be the same as that for a 26 inch bike.

    I'm 5'11" with an inseam of 33.5"

  2. #2
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    You are correct. You will need a larger frame. 29ers sit higher, especially in the front so standover is a lot less than a 26er. If you want more standover, and the top tube length of the 17" is good for you then you can use a longer seatpost (400mm) so that you can get the seatheight right.
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  3. #3
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    I'm 6'1" with a standover of 33". I went with the 17" and the TT just brushes, which is fine with me. The stock seat post *was* too short though. I switched to a Thudbuster that has a 400mm post, and it's now perfect. I'm at the 1 1/2 line on the Thud.

    P

  4. #4
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    I'm 5'9"and I have a 700DS with a 19" frame and it fits perfect but I just bought an 09 specialized rockhopper expert 29er and the 17" frame standover height fits me just right. I went to the specialized dealer and tried it out before I bought it.

  5. #5
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    I'm 6'0 with a 31 inch standover. I got a 17" Moto Outcast with a long, 400mm seatpost. Since I have a long torso, I also got a longer stem than the stock stem which was a POS anyway. Works well for me.

    bf

  6. #6
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    Hmmm. That sucks, they should have redesigned the frames so that longer seatposts should not be necessary. Is there a technical reason why the pedals need to be higher on the 29er's ?

    I'm considering getting the 19" fantom pro. The risk being I wont be able to have children, but at this point I dont think progeny will be forthcoming anyway

  7. #7
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    As a former bicycle mechanic and a long time rider, I firmly believe that ETT (effective top tube) is the correct way to size a frame. Sure, standover can be important but lets be honest, 99% time your actually riding the bike, not standing over it. I am 6' with shorter 32" legs and I would ride a 19" Motobecane 29er (I ride the Large Windsor which has a similar ETT as the 19" ). Yes, the standover is tight (but after riding 5" and 6" travel 26ers, I'm used to it now) but when riding, it feels right with a 110mm stem and 12* sweep bars (100mm with 9* sweep bars). A 17" has a 2.2cm shorter top tube than my Windsor which would necessitate at least a 130mm stem, too long for my taste. With you being a inch shorter and having 1.5" longer legs...its hard to say if the 17" would be an issue. I recommend measuring your ETT on your current 26er and compare it to the Moto 29er 17" and 19"...that should determine what size to get.

  8. #8
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    Quote Originally Posted by mtnbiker72
    As a former bicycle mechanic and a long time rider, I firmly believe that ETT (effective top tube) is the correct way to size a frame. Sure, standover can be important but lets be honest, 99% time your actually riding the bike, not standing over it. I am 6' with shorter 32" legs and I would ride a 19" Motobecane 29er (I ride the Large Windsor which has a similar ETT as the 19" ). Yes, the standover is tight (but after riding 5" and 6" travel 26ers, I'm used to it now) but when riding, it feels right with a 110mm stem and 12* sweep bars (100mm with 9* sweep bars). A 17" has a 2.2cm shorter top tube than my Windsor which would necessitate at least a 130mm stem, too long for my taste. With you being a inch shorter and having 1.5" longer legs...its hard to say if the 17" would be an issue. I recommend measuring your ETT on your current 26er and compare it to the Moto 29er 17" and 19"...that should determine what size to get.

    Thanks.
    According to http://motobecane.com/29geometry.html
    the top tube lenght difference between the 17" and 19" is just 0.4"; will that be noticeable ?

  9. #9
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    Maybe, maybe not. Your looking at 1 cm which could be made up in the stem (say a 100mm vs 110mm). Back when 19" frames had 22"-23" ETT's (90's) I regularly ran 135mm stems with 5* sweep bars. But ever since the late 90's when manufacturers started putting longer ETT's on their bikes, I've managed to use shorter stems, even as I've gone to greater sweep bars.

    The only other issue you might run into on a 17" is saddle to handlebar height. If your needing to use a long (400mm or more) seatpost, your likely going to have some drop from your saddle to handlebars. The racer boy types like this, but most recreational and trail riders prefer more of an even height. This may necessitate a higher rise stem as well.

  10. #10
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    Spot on...I love learning. As I was reading MB72's posts I realized that some of it applied to my 17" 29er Pro. My Bar/Seat height is about the same with the Thudbuster LT, but I don't know how it differs from a normal 400mm post. The stem length is where I see some room for improvement - I get front end lift going up moderately steep hills. I have to really concentrate to keep the front down (what's the right technique?) I dropped my bar on the stem by the 2 short spacers, to try and get some weight moved forward. Now I see that a 110mm stem may be better (assuming the 29er Pro comes with 1000mm?) But I'm still glad I got the 17" cuz when I'm riding with my 7 year old or in town (mailbox, stoplights) I'm always coming off the seat, over the TT...it feels like the right size. But yeah, a longer post and stem may need to be purchased. Or get the 19" and report back for future buyers

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