1. The most important thing about buying a new bike is to make sure it fits. The only way you'll know if the bike is right for you is to size up the bike and make sure that the bike's geometry matches your body's geometry. Ask questions and do some research.
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2. If possible, try to find a shop that will let you demo the bike on real dirt. Five minutes in a parking lot won't cut it. You wouldn't buy a car without a real world test drive, and a bike should be no different.
3. Don't belive the hype. Just because your favorite rider or best friend rides a certain bike, that doesn't mean that's the best one for you. Have an open mind and be realistic about your needs and ability.
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Thread: Stem length.

  1. #1
    {Believeland}
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    Stem length.

    My bike came with a 120mm stem with a 5 degree rise. It feels like i am leaning over the front end of the bike too much when i ride, as if the only thing that makes my bike (a medium size frame) fit me, is its longer stem. I almost feel awkward when i am riding it at times I know that the length of a stem affects how twitchy the steering is and how stable your front end is at high speeds. My question is, does the length of my stem affect my ability to manual and bunnyhop? I am able to get about 4 inches off the ground, but no higher. And no matter how much i practice and work on form it feels like there is something stopping me from getting more height Is it me or the stem?
    ride fast.... live slow

  2. #2
    namagomi
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    Longer stems make it harder to manual and bunnyhop(sure blame the stem!), it makes the steering inputs "slower"(think of a boat tiller), it makes it harder to descend and corner but easier to ascend.

  3. #3
    {Believeland}
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    thanks electrik, thats what i figured... now i don't feel so bad about myself
    ride fast.... live slow

  4. #4
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    electrik is spot on. You'll typically find longer stems on XC and race bikes. The longer stem positions the rider to pedal efficiently, takes the rider a bit out of the wind and helps to weigh the front wheel on climbs.

    But it sucks for all technical riding. Doesn't matter if you are looking into tricks or rough trail riding, FR or DH. For technical applications you want a shorter stem.

    Now: changing the stem is a pretty easy project and stems can be purchased cheap. So it makes total sense to have more than one. For learning tricks such as bunny hops I'd recommend either a very short stem (50mm) or something with a steep angle that brings the bar up. Essentially you want to have the bar close to the head tube and high up. This makes lifting the front for a bunny hop or a manual so much easier.

    Once you mastered the move - you'll find it all works with the long stem, too. But learning the move is so much easier with a short/high stem.
    "Lorem ipsum dolor sit amet, consectetuer adipiscing elit." - And I agree.

  5. #5
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    keep in mind...if you get a stem thats too short you might have a hard time keeping the front wheel on the ground when climbing

  6. #6
    Fat-tired Roadie
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    If you're too far forward with that stem but you think you need all 120mm to get a good fit, you're on too small a frame. Total bummer. What other lengths have you tried?

    As far as length effecting your ability to manual, bunnyhop, climb, etc, the above posters are right. The good news is that I think for most of us, there's a stem length that's long enough to climb and short enough to get that front wheel off the ground. If you have a local shop with a used stem bin, check it out. Otherwise, order a shorter one, or a couple if you have the budget, from someplace cheap. You can go back to bling when you find your One True Stem length.
    "Don't buy upgrades; ride up grades." -Eddy Merckx

  7. #7
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    Do a search on stem length and you will find pages and pages of awakened testimonials to the effect of "I went from 120-110-100 to 80-70-60-50mm and now I am a descending god".

    Personally I went from 100mm to 70mm and the difference is phenomenal. The fork doesn't blow through travel on descents or braking any more, the steering is quicker, I don't get that constant about-to-endo feeling when the bike points downward, wheelies are easier (manuals too, but I still can't do one). The kicker is, I'm riding a small size frame (Sette Flite 17") when I am 5'11" and should rightfully be on a medium, but even with the short stem I don't feel like I am cramped in the saddle, I just sit a bit more upright. The downside is front wheel wandering on steep climbs, but a fork with travel adjust fixes that.

    EDIT: Here's a nice diagram of stem and bar height.
    http://www.leelikesbikes.com/shorter...html#more-1237

  8. #8
    {Believeland}
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    yeah, its weird. cause im 5'11'' and on a medium frame. but i feel like if my stem were any shorter it would almost be unridable. It already seems pretty small on me as is And i was comparing my current frame dimensions to those of the potential bike i may be getting (size large), and the measurements are very similar, often times less than an inch. Now i know the geometry between all bikes are completely different, but i am concerned i will have this problem on my next bike too.
    ride fast.... live slow

  9. #9
    Fat-tired Roadie
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    I'm 5'8" and ride a medium as well. I find it to be a pretty comfortable size.

    But bear in mind that the proportions of bikes are based on the proportions of an idealized rider of a certain height. Someone with longer legs and a shorter torso would have a hard time finding a bike that had both a short enough top tube and a long enough head tube; someone with a long torso might find that bikes that put the bars in the right place didn't have enough standover clearance or put the bars far enough from the saddle but wouldn't let them be low enough.

    My point being that you really need to test-ride some bikes to figure it out. A lot of people, me included, believe in a "magic number" that's more important than any other measurement on the bike - effective top tube length. It shows up in almost all geometry charts, so if your ride a bunch of bikes and find one with a fit you like, you can look up the effective top tube length and be pretty confident that another bike with the same top tube length (assuming a similar cockpit setup) will give you a good fit as well.

    Stem length increments are pretty small, and the range of conventional MTB stems is about 65-120mm (last time I said this, someone jumped down my throat. Yes there are longer and shorter. They're just a little harder to find.) So if the bike companies are going to make bikes that let people choose a stem length and handlebar style based on desired handling characteristics, not just making the fit acceptable, they really shouldn't have more than about a 30mm increment on length. So yeah - that 1" or so increment is about right. But you might find an XL is a good fit for you.
    "Don't buy upgrades; ride up grades." -Eddy Merckx

  10. #10
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    Quote Originally Posted by AndrwSwitch
    I'm 5'8" and ride a medium as well. I find it to be a pretty comfortable size.
    ...
    My point being that you really need to test-ride some bikes to figure it out. A lot of people, me included, believe in a "magic number" that's more important than any other measurement on the bike - effective top tube length. It shows up in almost all geometry charts, so if your ride a bunch of bikes and find one with a fit you like, you can look up the effective top tube length and be pretty confident that another bike with the same top tube length (assuming a similar cockpit setup) will give you a good fit as well.
    Hmm, maybe that explains why I feel fine riding a size "small" (with a stem between 70-90mm) when the geometry charts for the Flite AM say I should be between medium and large: the effective top tube is 56.5cm. I am 5'11" and ride a 56cm/22" TT road bike (with 100mm stem). The medium Flite has a length of 58.5cm/23" which seems a bit much for me. Also, my inseam is 32" and the medium has a standover height of 31.75", which is quite below the recommended 2" for mountain bikes. The small has 30.25", much more reasonable. So, despite the geometry charts, a size small seems to fit me OK, even if I have a bit more seatpost showing to make up for the 1" shorter seat tube. Mountain bike fits are kinda weird it seems, there are more variables than with road bike fitting.

  11. #11
    {Believeland}
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    I think i am just gonna have to go with a test ride to determine the size i will need But because of the technical riding i do, I have a feeling i will end up going with a large, since a shorter stem is preferable for the type of riding i do.
    ride fast.... live slow

  12. #12
    Fat-tired Roadie
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    Quote Originally Posted by derailin_palin
    Hmm, maybe that explains why I feel fine riding a size "small" (with a stem between 70-90mm) when the geometry charts for the Flite AM say I should be between medium and large: the effective top tube is 56.5cm. I am 5'11" and ride a 56cm/22" TT road bike (with 100mm stem). The medium Flite has a length of 58.5cm/23" which seems a bit much for me. Also, my inseam is 32" and the medium has a standover height of 31.75", which is quite below the recommended 2" for mountain bikes. The small has 30.25", much more reasonable. So, despite the geometry charts, a size small seems to fit me OK, even if I have a bit more seatpost showing to make up for the 1" shorter seat tube. Mountain bike fits are kinda weird it seems, there are more variables than with road bike fitting.
    You need to be a little careful about comparing top tube lengths across bicycle types. A typical road bike configuration might be a 100mm stem, drop bars, and aero brakes. The current fashion is to ride with one's hands on the brake hoods. The drop bars and aero brakes add a few inches to the reach.

    An old-school flat bar with no bend would not change the reach at all, but most of us have at least a little sweep on our mountain bikes. Depending on the amount of sweep, the bars will subtract a fraction of an inch from the reach.

    Of course, most people who ride both types of bikes also have different riding positions. I'm enough of a geek to record the reaches on my "fun" bikes. Seat post to bar clamp on my 'cross bike is 24", on my road bike is 26" and on my mountain bike is 27". So including hoods, the longest reach is on my road bike and my mountain and cross bikes are probably about the same. However, my top tube lengths are pretty different from bike to bike.

    OP, you're right - riding a lot of bikes is the only way to figure it out. Off-road if at all possible.
    "Don't buy upgrades; ride up grades." -Eddy Merckx

  13. #13
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    Quote Originally Posted by XCkiller
    yeah, its weird. cause im 5'11'' and on a medium frame. but i feel like if my stem were any shorter it would almost be unridable. It already seems pretty small on me as is And i was comparing my current frame dimensions to those of the potential bike i may be getting (size large), and the measurements are very similar, often times less than an inch. Now i know the geometry between all bikes are completely different, but i am concerned i will have this problem on my next bike too.
    At 5'11 your what I like to call a tweener. A medium feels just a little small and a large feels just a little big, but that's just the 100mm XC stem that comes on most bikes that exaggerates the cock pit during the fitting at the LBS, so when you change the stem (like we all do) the bike all of a sudden doesn't fit as well.. Get a frame with a 24" TT length and then you could ride shorter stems and still have a comfortable cock pit for all day epics. As a tweener you will not be able to throw the LG bike around as easily as your M. It will feel a little slow, sluggish and clumsy in turn (especially switch backs) at first. but that will change with seat time and a little tweek-n.
    Last edited by Drth Vadr; 01-22-2010 at 09:41 AM.

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