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  1. #1
    mak
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    New question here. Proper Stem Length

    I own 98 Litespeed OBED. I am 510, 32 inseam, bit longer torso. I currently have a 110mm stem on my bike. It has been recommended that I move to a 130mm stem. Is this too long of a stem? Does anyone own a similar bike that can share thoughts? With the 110mm stem, I do feel a bit rear heavy and my turns seem to be on the outside (i.e., turns are not very quick). I do like the lighter back end at times to get over obstacles. I was told the 130mm will balance me out and help with climbs and turns. HELP!

  2. #2
    jcw
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    Quote Originally Posted by mak
    I own 98 Litespeed OBED. I am 510, 32 inseam, bit longer torso. I currently have a 110mm stem on my bike. It has been recommended that I move to a 130mm stem. Is this too long of a stem? Does anyone own a similar bike that can share thoughts? With the 110mm stem, I do feel a bit rear heavy and my turns seem to be on the outside (i.e., turns are not very quick). I do like the lighter back end at times to get over obstacles. I was told the 130mm will balance me out and help with climbs and turns. HELP!
    Well it's impossible to tell if a longer stem will be a good move given the lack of information. Also what you say doesn't make sense - a shorter stem should result in quicker steering and make for more weight on the "back end". What I can tell you is that if your cockpit is too short, you will have a hard time keeping your front wheel down on climbs, and the front wheel will have a tendancy to wash out on corners while descending. If you're not having either of those problems, then the stem you have is probably fine. A number of years ago, on a bike with a 23.5" effective top tube, I ran a 135mm stem and felt it was perfect. My current bike has a longer top tube (24.5") so now I'm using a bit shorter stem (120mm). So who made this recommendation anyway? If it was someone at a LBS, ask if they'll let you put it on and try it out. If not, perhaps a riding buddy has an old longer stem laying around you can try. 130mm and longer stems were quite common a few years back.

  3. #3

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    Stem Length

    I generally use the "bar over the hub method" to determine if my stem is the correct size. While riding in a straight line, check and see if the center of your handlebar is directly over the center of the hub when your looking down, try not to eat it though. If the bar is behind the hub, your stem is too short, if it's in front of the hub, it's too long. Playing with the fore and aft of the seat can help if you don't want to buy a new stem. Not the scientific approach, but it has worked for me over the last 12 years of mountain biking.

  4. #4

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    This works, but...

    Quote Originally Posted by slp999
    I generally use the "bar over the hub method" to determine if my stem is the correct size. While riding in a straight line, check and see if the center of your handlebar is directly over the center of the hub when your looking down, try not to eat it though. If the bar is behind the hub, your stem is too short, if it's in front of the hub, it's too long. Playing with the fore and aft of the seat can help if you don't want to buy a new stem. Not the scientific approach, but it has worked for me over the last 12 years of mountain biking.
    You have to start with perfect saddle position, otherwise the bar will wind up in the wrong place.

    DO NOT use saddle fore and aft to lengthen the tt length. The fore and aft is used to center your body over the cranks.

  5. #5
    jcw
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    Quote Originally Posted by slp999
    I generally use the "bar over the hub method" to determine if my stem is the correct size.
    Good advice there, just keep in mind that this is a general "rule of thumb", that may or may not hold true. My current mtn bike stem would be considered too long by that measure.

    Quote Originally Posted by slp999
    Playing with the fore and aft of the seat can help if you don't want to buy a new stem.
    Oooohhh, I cringe whenever I hear that. As a big believer in KOPS (knee over pedal spindle), I believe that saddle fore/aft position should never be used to change cockpit length, only to get the proper knee position.

  6. #6

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    So true.

    Quote Originally Posted by jcw
    Good advice there, just keep in mind that this is a general "rule of thumb", that may or may not hold true. My current mtn bike stem would be considered too long by that measure.



    Oooohhh, I cringe whenever I hear that. As a big believer in KOPS (knee over pedal spindle), I believe that saddle fore/aft position should never be used to change cockpit length, only to get the proper knee position.
    I fit bikes for a living, and I also cringe when I hear that. (or is it my knees cringing?)

  7. #7
    nab
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    The position that feels best should right, isn't it? We have different inseam, torso, reach, balance, weight etc... The technique mentioned just serves as a guideline, you should try as many different combinations and pick the best.

  8. #8
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    Hey nab

    I agree,adjust your saddle for-aft then leave it alone.
    This is not the end of all but rather what works for me,i sit on my bike leaning against the wall or something else keeping the bike as straight as possible,i then use a string with a weight on the end of it and hang it down from that small pit under your knee cap.The string should line up with your pedal spindle or slightly behind for better climbing.Remember to do this with your pedals parallel to the ground.I experience no knee pain from this method.
    Now about the stem,i have the same issues mainly because i always opt for the smaller frame when i'm caught between a med or large.For some unknown reason new bikes are coming stock with shorter stems for comfort and thats fine until the trail starts up.My last two bikes had 100mm stems and i quikly replaced them with 120mm.Its a quik and easy change so try differant sizes until you feel confortable.
    NOTE: i use 6deg rise and found anthing over 120mm in stem lenght to encourage endovers .

  9. #9

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    confusing information = bad recommendations

    Quote Originally Posted by mak
    I own 98 Litespeed OBED. I am 5?10, 32? inseam, bit longer torso. I currently have a 110mm stem on my bike. It has been recommended that I move to a 130mm stem. Is this too long of a stem? Does anyone own a similar bike that can share thoughts? With the 110mm stem, I do feel a bit rear heavy and my turns seem to be on the outside (i.e., turns are not very quick). I do like the lighter back end at times to get over obstacles. I was told the 130mm will balance me out and help with climbs and turns. HELP!
    I'll try to help but you need to answer a few Qs first.

    1) What size is the top tube on your Obed?

    2) what is your arm (sleeve) length?

    3) what type of riding do you prefer to do?

    4) what aspect of your riding do you feel is weakest -- or, said differently, do you have any particular bike handling problems?

    5) why are you considering the stem change?

    Now, as to the others' answers, I think...

    "handlebar obscuring front hub" ---> this is PURE road bike apocrypha. it may work for you on your road bike, it may not... but it DOESN"T apply to mtb riding AT ALL.

    "knee over pedal spindle" ---> this is another bit of road bike apocrypha. it's a STARTING POINT for road riding positions.

    "using saddle fore/aft to compensate for top tube differences" ---> DEAD WRONG. saddle fore/aft is purely to adjust your hips' position relative to the BB/crank. another 2 factors in this positioning are the seatpost setback and the frame's seat tube angle.

    Different riders and different riding styles make the first two notions useless even for road riding. And, the differences in MTB geometry (versus road bike geometry) cause these two notions to fall away immediately for MTB applications.

    What works best is to learn what type of muscles you use when pedaling. If you're mostly a hamstring/pulling pedaler, a more forward saddle usually best accommodates such a pedaling style. For quad-using "mashers" who pedal squares and emphasize the "push" part of pedaling, a more aftward position usually is preferable.

    As to stem length, there are no fast rules for proper length. My best lengths are short, I dislike the bad steering effects (pushy steering, tiller effects, too much front wheel weight) and endo-prone nature of stems longer than 110mm or so. Other riders prefer stems no shorter than 110mm.

    Shorter stems put your weight balance more rearward, and tend to make the front wheel "lighter" in climbs and turns. The steering feels much more neutral, and occurs more from behind the front wheel, instead of OVER the front wheel.

    Longer stems put your weight on the front wheel. This helps front wheel tracking when tackling steeper climbs. However, it also makes the bike's steering react more quickly to small rider inputs. When turning, it may feel like you are out over the front wheel and steering from a point that's somewhat ahead of the bike.

    Your turning style and climbing style will dictate what length stem you like best.

    Remember that handlebar width and rise also affect steering and weight distribution.

  10. #10
    jcw
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    Sorry Sean, gotta disagree with you on one point.

    Quote Originally Posted by gonzostrike
    "knee over pedal spindle" ---> this is another bit of road bike apocrypha. it's a STARTING POINT for road riding positions.
    Yes and no. I think it still applies to those like me who are purely xc riders and spend a majority of their riding time, especially climbing, seated and spinning. If you're a freerider (like you) riding a slacked out rig, then it may well be physically impossible to achieve KOPS even if you wanted to. But I still feel that for seated and spinning type riding, KOPS is a good thing and can reduce stress on the knee. For anything other than purely xc riding on an xc bike though, I agree completely that it's meaningless.

    Anyway, If you find yourself in Red Lodge in the near future, stop in. The shop should be up and running by the end of April.

    Cheers,
    John Wood

  11. #11

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    Hey John, how's it going?

    Quote Originally Posted by jcw
    Sorry Sean, gotta disagree with you on one point.

    Yes and no. I think it still applies to those like me who are purely xc riders and spend a majority of their riding time, especially climbing, seated and spinning.

    Anyway, If you find yourself in Red Lodge in the near future, stop in. The shop should be up and running by the end of April.

    Cheers,
    John Wood
    Good news, good to hear from ya. I agree on XC-position riding, especially for those who set up their XC bikes to mimic their road bikes... I used to have my XC racer set up as close to my roadie as I could get it and still descend safely. But my KOPS thing is anti- only because we all have different optimal leverage points. Some folks get more power with +KOPS, some with -KOPS. And, I believe that you can change KOPS differences with changes in saddle height. I think the less one rides than 90% in-saddle (i.e. like a road ride), the less relevant KOPS becomes. But I would agree completely that it's a great starting point to help a developing cyclist prevent joint strain. It would not be wise for a newly serious rider to emulate a position that's (+) or (-) from KOPS just because his/her favorite rider (pro, whatever) uses that position.

    I'll let you know if I'll be down that way. Say hey to Heidi for me.

    Sean

  12. #12
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    Upset Good info..........No rights or wrongs....

    Quote Originally Posted by gonzostrike
    I'll try to help but you need to answer a few Qs first.

    1) What size is the top tube on your Obed?

    2) what is your arm (sleeve) length?

    3) what type of riding do you prefer to do?

    4) what aspect of your riding do you feel is weakest -- or, said differently, do you have any particular bike handling problems?

    5) why are you considering the stem change?

    Now, as to the others' answers, I think...

    "handlebar obscuring front hub" ---> this is PURE road bike apocrypha. it may work for you on your road bike, it may not... but it DOESN"T apply to mtb riding AT ALL.

    "knee over pedal spindle" ---> this is another bit of road bike apocrypha. it's a STARTING POINT for road riding positions.

    "using saddle fore/aft to compensate for top tube differences" ---> DEAD WRONG. saddle fore/aft is purely to adjust your hips' position relative to the BB/crank. another 2 factors in this positioning are the seatpost setback and the frame's seat tube angle.

    Different riders and different riding styles make the first two notions useless even for road riding. And, the differences in MTB geometry (versus road bike geometry) cause these two notions to fall away immediately for MTB applications.

    What works best is to learn what type of muscles you use when pedaling. If you're mostly a hamstring/pulling pedaler, a more forward saddle usually best accommodates such a pedaling style. For quad-using "mashers" who pedal squares and emphasize the "push" part of pedaling, a more aftward position usually is preferable.

    As to stem length, there are no fast rules for proper length. My best lengths are short, I dislike the bad steering effects (pushy steering, tiller effects, too much front wheel weight) and endo-prone nature of stems longer than 110mm or so. Other riders prefer stems no shorter than 110mm.

    Shorter stems put your weight balance more rearward, and tend to make the front wheel "lighter" in climbs and turns. The steering feels much more neutral, and occurs more from behind the front wheel, instead of OVER the front wheel.

    Longer stems put your weight on the front wheel. This helps front wheel tracking when tackling steeper climbs. However, it also makes the bike's steering react more quickly to small rider inputs. When turning, it may feel like you are out over the front wheel and steering from a point that's somewhat ahead of the bike.

    Your turning style and climbing style will dictate what length stem you like best.

    Remember that handlebar width and rise also affect steering and weight distribution.

    The whole stem length is really about center of gravity. Where you put your center of gravity in relation to the rest of the bike/front wheel/rear wheel will cause your bike to "handle" certain way.

    Stem length is only one part of the equation. You've got to look at stem length, stem height (changed with spacers or a great angled stem) and TT. We'll keep other impacting factors constant (HA, body type...high-front center of gravity witha rider with a big upper body and thin legs vs. thick legs and no upper body, crown to axel length of the fork, sag of the fork...).

    Anything (shorter stem, taller stem, riser bars...) that puts your weight farther away and behind the front end or front hub will unweight the front end. This results is front end steering a bit more prone to "push through" and wash out. It's less than ideal on smooth, tight, twisty single track but will make you more endo proof on the downhills and technical stuff. On the other hand a longer or lower stem will weight your front end and make the front tire stick and give you great cornering ability but will make you endo prone.

    Don't you believe for one second that old roadie BS about determinig your proper overall length. Putting someone on a bike with short TT and a long stem just to get that "proper overall reach" is almost total nonsence. Go ahead and put a 130mm, 0 rise stem on my large Heckler with a 23.3 tt to get the proper fit...you'll set me endoing on every downhill. "Fitting" someone to a mountain bike is more about getting them on a bike with a tt and stem that will lead to the bike handling attributes that fits the rider's style.

  13. #13
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    My thoughts:

    1) KOPS does not work for everyone. I tried KOPS for years and the result was sore knees and pain. For me going about 1/2"-1" forward of KOPS was where everything felt correct (this is true for both mountain bikes and my roadbikes).

    2) Many people forget about how important the balance point on a bike really is. To give you an idea, for years I rode my Fisher (genesis geometry) with the stock setback seatpost and a 105mm 15 degree stem. I loved the bike, but always had problems with climbing and hand numbness. I recently bought a Turner and it required a rethinking of my whole position. On the turner I was farther forward on the pedals (with a straight seatpost as recomended by turner) and 110mm stem. The cockpit felt very small (the toptube on the fisher is .75" longer and it also had a 1" setback post). After riding the Turner a bit I found it felt very comfortable, which led me to the rethinking of my Fisher fit. I changed to a straight post, and ended up with a 90mm stem (effective cockpit shrunk 1.5"). I feel so much better balanced now, can climb better, decend better and no hand numbness, knees are better. I also ended up moving the seat .75" forward on my roadbike, and guess what, the squirely steering is cured.

    3) Be sure to experiment with position. KOPS can give you a starting point, but you may find that your ideal position is not near KOPS. Do not be afraid to move the seat forward or back and ride a while to see if it works better. Don't forget when you move the seat forward and back, that you may want to raise or lower it slightly also.

  14. #14
    jcw
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    Excellent post CD, couldn't have put it better myself. There are a number of "rules of thumb" for bike fitting, and are generally a good guideline for the inexperienced cyclist. Cockpit length is especially subject to rider preference. My preferred cockpit length is a whopping 3.2cm longer than what a professional fit dictated based on my body proportions and flexability. A change of 1/8th inch can have a very noticable effect on handling, so that's huge. What makes this especially suprising is that I'm not at all flexible, and I have 2 herniated disc's - which logic would tell you would necessitate a shorter cockpit. But if I shorten my cockpit, my handling goes to hell. Unfortunately there are so many variables that are impossible to measure, that bike fitting is definitely more of an art than science, and to really dial it in takes some experimentation. My one word of caution is to make changes, especially saddle position, in small increments (~1.8th inch) - especially if you've been riding for a long time. Your body (muscles and tendons) adapt to whatever position you're using, even if it's wrong. A sudden, large change can wreak havoc, even it it's technically "better".

    Quote Originally Posted by CDMC
    My thoughts:

    1) KOPS does not work for everyone. I tried KOPS for years and the result was sore knees and pain. For me going about 1/2"-1" forward of KOPS was where everything felt correct (this is true for both mountain bikes and my roadbikes).

    2) Many people forget about how important the balance point on a bike really is. To give you an idea, for years I rode my Fisher (genesis geometry) with the stock setback seatpost and a 105mm 15 degree stem. I loved the bike, but always had problems with climbing and hand numbness. I recently bought a Turner and it required a rethinking of my whole position. On the turner I was farther forward on the pedals (with a straight seatpost as recomended by turner) and 110mm stem. The cockpit felt very small (the toptube on the fisher is .75" longer and it also had a 1" setback post). After riding the Turner a bit I found it felt very comfortable, which led me to the rethinking of my Fisher fit. I changed to a straight post, and ended up with a 90mm stem (effective cockpit shrunk 1.5"). I feel so much better balanced now, can climb better, decend better and no hand numbness, knees are better. I also ended up moving the seat .75" forward on my roadbike, and guess what, the squirely steering is cured.

    3) Be sure to experiment with position. KOPS can give you a starting point, but you may find that your ideal position is not near KOPS. Do not be afraid to move the seat forward or back and ride a while to see if it works better. Don't forget when you move the seat forward and back, that you may want to raise or lower it slightly also.

  15. #15
    simply me
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    Interesting article on why KOP's is BS...

    http://www.sheldonbrown.com/kops.html

    p.s.If KOPS is it, those poor recumbant riders knee's must ache, can a knee be any further away from over the pedal!
    Last edited by bostonkiwi; 03-29-2004 at 10:53 AM.

  16. #16
    mak
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    Response to stem length.

    Thank you for the information. Here is the info that you requested, I hope this helps:
    1) What size is the top tube on your Obed? 22.75

    2) what is your arm (sleeve) length? Quick measure is 29.5 - 30 from shoulder to middle finger. I measure real quick with ruler

    3) what type of riding do you prefer to do? Heavy XC rides with roots, rocky sections, etc.

    4) what aspect of your riding do you feel is weakest -- or, said differently, do you have any particular bike handling problems? On trails tend to wash out on turns, pop front tire up on climbs.

    5) why are you considering the stem change?LBS advised on 130mm stem after fitting my bike.






    QUOTE=Miker J]The whole stem length is really about center of gravity. Where you put your center of gravity in relation to the rest of the bike/front wheel/rear wheel will cause your bike to "handle" certain way.

    Stem length is only one part of the equation. You've got to look at stem length, stem height (changed with spacers or a great angled stem) and TT. We'll keep other impacting factors constant (HA, body type...high-front center of gravity witha rider with a big upper body and thin legs vs. thick legs and no upper body, crown to axel length of the fork, sag of the fork...).

    Anything (shorter stem, taller stem, riser bars...) that puts your weight farther away and behind the front end or front hub will unweight the front end. This results is front end steering a bit more prone to "push through" and wash out. It's less than ideal on smooth, tight, twisty single track but will make you more endo proof on the downhills and technical stuff. On the other hand a longer or lower stem will weight your front end and make the front tire stick and give you great cornering ability but will make you endo prone.

    Don't you believe for one second that old roadie BS about determinig your proper overall length. Putting someone on a bike with short TT and a long stem just to get that "proper overall reach" is almost total nonsence. Go ahead and put a 130mm, 0 rise stem on my large Heckler with a 23.3 tt to get the proper fit...you'll set me endoing on every downhill. "Fitting" someone to a mountain bike is more about getting them on a bike with a tt and stem that will lead to the bike handling attributes that fits the rider's style.[/QUOTE]

  17. #17
    mak
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    Response to stem length.

    Thank you for the information. Here is the info that you requested, I hope this helps:
    1) What size is the top tube on your Obed? 22.75

    2) what is your arm (sleeve) length? Quick measure is 29.5 - 30 from shoulder to middle finger. I measure real quick with ruler

    3) what type of riding do you prefer to do? Heavy XC rides with roots, rocky sections, etc.

    4) what aspect of your riding do you feel is weakest -- or, said differently, do you have any particular bike handling problems? On trails tend to wash out on turns, pop front tire up on climbs.

    5) why are you considering the stem change?LBS advised on 130mm stem after fitting my bike.






    QUOTE=Miker J]The whole stem length is really about center of gravity. Where you put your center of gravity in relation to the rest of the bike/front wheel/rear wheel will cause your bike to "handle" certain way.

    Stem length is only one part of the equation. You've got to look at stem length, stem height (changed with spacers or a great angled stem) and TT. We'll keep other impacting factors constant (HA, body type...high-front center of gravity witha rider with a big upper body and thin legs vs. thick legs and no upper body, crown to axel length of the fork, sag of the fork...).

    Anything (shorter stem, taller stem, riser bars...) that puts your weight farther away and behind the front end or front hub will unweight the front end. This results is front end steering a bit more prone to "push through" and wash out. It's less than ideal on smooth, tight, twisty single track but will make you more endo proof on the downhills and technical stuff. On the other hand a longer or lower stem will weight your front end and make the front tire stick and give you great cornering ability but will make you endo prone.

    Don't you believe for one second that old roadie BS about determinig your proper overall length. Putting someone on a bike with short TT and a long stem just to get that "proper overall reach" is almost total nonsence. Go ahead and put a 130mm, 0 rise stem on my large Heckler with a 23.3 tt to get the proper fit...you'll set me endoing on every downhill. "Fitting" someone to a mountain bike is more about getting them on a bike with a tt and stem that will lead to the bike handling attributes that fits the rider's style.[/QUOTE]

  18. #18
    mak
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    Response to stem length.

    Thank you for the information. Here is the info that you requested, I hope this helps:
    1) What size is the top tube on your Obed? 22.75

    2) what is your arm (sleeve) length? Quick measure is 29.5 - 30 from shoulder to middle finger. I measure real quick with ruler

    3) what type of riding do you prefer to do? Heavy XC rides with roots, rocky sections, etc.

    4) what aspect of your riding do you feel is weakest -- or, said differently, do you have any particular bike handling problems? On trails tend to wash out on turns, pop front tire up on climbs.

    5) why are you considering the stem change?LBS advised on 130mm stem after fitting my bike.






    QUOTE=Miker J]The whole stem length is really about center of gravity. Where you put your center of gravity in relation to the rest of the bike/front wheel/rear wheel will cause your bike to "handle" certain way.

    Stem length is only one part of the equation. You've got to look at stem length, stem height (changed with spacers or a great angled stem) and TT. We'll keep other impacting factors constant (HA, body type...high-front center of gravity witha rider with a big upper body and thin legs vs. thick legs and no upper body, crown to axel length of the fork, sag of the fork...).

    Anything (shorter stem, taller stem, riser bars...) that puts your weight farther away and behind the front end or front hub will unweight the front end. This results is front end steering a bit more prone to "push through" and wash out. It's less than ideal on smooth, tight, twisty single track but will make you more endo proof on the downhills and technical stuff. On the other hand a longer or lower stem will weight your front end and make the front tire stick and give you great cornering ability but will make you endo prone.

    Don't you believe for one second that old roadie BS about determinig your proper overall length. Putting someone on a bike with short TT and a long stem just to get that "proper overall reach" is almost total nonsence. Go ahead and put a 130mm, 0 rise stem on my large Heckler with a 23.3 tt to get the proper fit...you'll set me endoing on every downhill. "Fitting" someone to a mountain bike is more about getting them on a bike with a tt and stem that will lead to the bike handling attributes that fits the rider's style.[/QUOTE]

  19. #19
    mak
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    Revise

    Approx. 30" - Sorry, but I am using a ruler. FYI, I am pretty standard in arm length. I cant recall sleeve length.

    Quote Originally Posted by mak
    Thank you for the information. Here is the info that you requested, I hope this helps:
    1) What size is the top tube on your Obed? 22.75

    2) what is your arm (sleeve) length? Quick measure is 30" from shoulder to middle finger. I measure real quick with ruler

    3) what type of riding do you prefer to do? Heavy XC rides with roots, rocky sections, etc.

    4) what aspect of your riding do you feel is weakest -- or, said differently, do you have any particular bike handling problems? On trails tend to wash out on turns, pop front tire up on climbs.

    5) why are you considering the stem change?LBS advised on 130mm stem after fitting my bike.






    QUOTE=Miker J]The whole stem length is really about center of gravity. Where you put your center of gravity in relation to the rest of the bike/front wheel/rear wheel will cause your bike to "handle" certain way.

    Stem length is only one part of the equation. You've got to look at stem length, stem height (changed with spacers or a great angled stem) and TT. We'll keep other impacting factors constant (HA, body type...high-front center of gravity witha rider with a big upper body and thin legs vs. thick legs and no upper body, crown to axel length of the fork, sag of the fork...).

    Anything (shorter stem, taller stem, riser bars...) that puts your weight farther away and behind the front end or front hub will unweight the front end. This results is front end steering a bit more prone to "push through" and wash out. It's less than ideal on smooth, tight, twisty single track but will make you more endo proof on the downhills and technical stuff. On the other hand a longer or lower stem will weight your front end and make the front tire stick and give you great cornering ability but will make you endo prone.

    Don't you believe for one second that old roadie BS about determinig your proper overall length. Putting someone on a bike with short TT and a long stem just to get that "proper overall reach" is almost total nonsence. Go ahead and put a 130mm, 0 rise stem on my large Heckler with a 23.3 tt to get the proper fit...you'll set me endoing on every downhill. "Fitting" someone to a mountain bike is more about getting them on a bike with a tt and stem that will lead to the bike handling attributes that fits the rider's style.
    [/QUOTE]

  20. #20

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    my Obed

    I'm a "medium" and got an 18.5" Obed, a real early one, when they were still pop riveting on the cable stops. Got a 135mm x0 degree Ringle stem on mine with a low riser bar. Couldn't fit better. Back when the bike was new, a 110mm stem was considered freakishly short, something for petite chicks. 120mm was about the shortest you'd normally see, with 135mm being the defacto standard, and 150mm available for pituitary cases.
    I dunno about freeride and dh bikes, but normal hardtail xc bikes steer better with longish stems. with a 135 the bike "steers from the hips" as they say, but with a short stem it requires a more deliberate steering input at the handlebar which I don't like at all.

  21. #21
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    Quote Originally Posted by bulC
    I'm a "medium" and got an 18.5" Obed, a real early one, when they were still pop riveting on the cable stops. Got a 135mm x0 degree Ringle stem on mine with a low riser bar. Couldn't fit better. Back when the bike was new, a 110mm stem was considered freakishly short, something for petite chicks. 120mm was about the shortest you'd normally see, with 135mm being the defacto standard, and 150mm available for pituitary cases.
    I dunno about freeride and dh bikes, but normal hardtail xc bikes steer better with longish stems. with a 135 the bike "steers from the hips" as they say, but with a short stem it requires a more deliberate steering input at the handlebar which I don't like at all.

    Not necessarly true, I think it is an old wives tail. I run a 90mm stem on my Fisher Hardtail which has a long top tube and it is very stable and easy to ride. I would focus more on balance and how the fit feels than worrying if it is a 90mm or 140mm stem that gives you the proper feel.

  22. #22
    mak
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    thanks for info.

    I agree. I think the frame has a shorter tube length which requires longer stem. I have the seat tube and saddle adjust for 30 degree bend and knees slightly behind spindle.

  23. #23
    Bike to the Bone...
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    Quote Originally Posted by slp999
    I generally use the "bar over the hub method" to determine if my stem is the correct size. While riding in a straight line, check and see if the center of your handlebar is directly over the center of the hub when your looking down, try not to eat it though. If the bar is behind the hub, your stem is too short, if it's in front of the hub, it's too long. Playing with the fore and aft of the seat can help if you don't want to buy a new stem. Not the scientific approach, but it has worked for me over the last 12 years of mountain biking.
    the "bar over the hub method" may not be too acurate, IMHO, because of the different head angles. So, let's say you have the right 'cockpit size', but on different bikes, most probably, both will have a different wheelbase length. But I think it's a good starting point.

  24. #24
    Rollin' a fatty
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    I have a Specialed 130mm stem that you can have for $10 and the cost of shipping, PM me if interested.

  25. #25
    Nouveau Retrogrouch SuperModerator
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    Quote Originally Posted by slp999
    I generally use the "bar over the hub method" to determine if my stem is the correct size. While riding in a straight line, check and see if the center of your handlebar is directly over the center of the hub when your looking down, try not to eat it though. If the bar is behind the hub, your stem is too short, if it's in front of the hub, it's too long. Playing with the fore and aft of the seat can help if you don't want to buy a new stem. Not the scientific approach, but it has worked for me over the last 12 years of mountain biking.
    Totally useless method.

    Depending on how I arch or do not arch my back, or bend my elbows I can "move" the bar several inches in front of or behind the hub.
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