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  1. #1
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    who run with 30mm stem?

    hey

    Im curious if any of you have experience running 30mm and 50mm stems and compare differences? What brands do sell such short stems?

    Im 5"10 (177cm) and planing a bit larger frames than normally suited for me. With 30mm stems reach will be good but I get curious what kind of challenges one gets with such short stem? Especially climbing, cornering. I assume that on downhill it makes more stable due longer TT/WB.

    I also have DH rig and may switch to larger frame and short stem as well.

    If there is no large difference, then I may switch to short stem.

  2. #2
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    I have a cromag ranger stem in 40mm. I'm the same height as you with a 32" inseam so when I rode the medium the reach is great, but the seat post wasn't long enough. I ended up getting a large frame on my bike and putting the shorter stem. Feels great.

  3. #3
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    Quote Originally Posted by tomasis View Post
    hey

    Im curious if any of you have experience running 30mm and 50mm stems and compare differences? What brands do sell such short stems?

    Im 5"10 (177cm) and planing a bit larger frames than normally suited for me. With 30mm stems reach will be good but I get curious what kind of challenges one gets with such short stem? Especially climbing, cornering. I assume that on downhill it makes more stable due longer TT/WB.

    I also have DH rig and may switch to larger frame and short stem as well.

    If there is no large difference, then I may switch to short stem.
    Syntace 30mm Megaforce2 stem as that seems to be the stem guys are running on their large V2 Rune's for guys in the 5'10"-5'11" range, and the stem I would be running if I went large as my 50mm stem would be too long with the long reach of the V2. I am 5'9" no shoes, closer to 5'10" w/bike shoes on and looking like I am going medium V2 w/50 stem as medium V2 has same wheelbase and reach of the AM bike that I am on now despite and inch shorter ST and TT. I don't think you will have any issue with climbing at all with 30mm stem due to longer reach on that bike. I never ran shorter than 45mm stem in the past on bikes, but never felt a loss of climbing when going shorter in stem and gained control and better steering with shorter stem, especially when accompanied with wider bars which adds much stability, but slows steering down.

    Another stem to consider is Straightline 35mm as it looks much nicer than the Syntace and comes in different colors. But, the 30mm would be nice and looks like the Syntace is designed well with being one of the lightest short stems out there. Go Syntace Megaforce2 30mm if you don't mind the bland color and appearance, Straightline if wanting a tit longer with better colors and anodizing.
    Ride On!

  4. #4
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    Quote Originally Posted by tomasis View Post
    hey

    Im curious if any of you have experience running 30mm and 50mm stems and compare differences? What brands do sell such short stems?

    Im 5"10 (177cm) and planing a bit larger frames than normally suited for me. With 30mm stems reach will be good but I get curious what kind of challenges one gets with such short stem? Especially climbing, cornering. I assume that on downhill it makes more stable due longer TT/WB.

    I also have DH rig and may switch to larger frame and short stem as well.

    If there is no large difference, then I may switch to short stem.
    My current trail bike (Turner 5 spot) has the same reach to the bars as my previous AM bikes, but has a longer tt and shorter stem. Last bike had a 60mm stem, this one is 45mm to get the same reach.

    It does seem little more stable on DH runs, and it's nice in the really steep stuff. Not much different climbing, it's really just technique to keep the front end down.

    However, all-around, I'm not sure I really like it. It takes a more concerted effort to plant the front end in turns, and on some slower rough stuff, I feel like the front end is too unweighted. The bike just feels like the front wheel is too far out in front of me for my all around needs. The slighter slacker head angle in addition to the longer tt explains this.

    I have stuck a 45mm stem on my previous (shorter top tube) bikes for special occasions, like visiting a lift served park, and that felt fine. Super fun, actually, though it was a little cramped for all round riding.

    That's my experience, anyway.
    15mm is a second-best solution to a problem that was already solved.

  5. #5
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    Quote Originally Posted by jgusta View Post
    a tit longer
    i wish my stem was a tit longer

  6. #6
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    Quote Originally Posted by b-kul View Post
    i wish my stem was a tit longer
    I don't know, afraid it would be a major distraction..the tit that is
    Ride On!

  7. #7
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    interesting to hear that it doesnt affect climbing. Good point about wider handlebar balancing up twitchier handling caused by shorter stem.

  8. #8
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    Quote Originally Posted by tomasis View Post
    interesting to hear that it doesnt affect climbing. Good point about wider handlebar balancing up twitchier handling caused by shorter stem.
    Wide bars, short stems are a match made in heaven on all bikes in my opinion from trail to DH. If you have enough reach on bike, stem length shouldn't make that much difference in climbing, especially with the large V2 at 17.4" reach, unless maybe you have a really long torso and arms for your height. For the large V2, typically a <50mm stem will be a necessity at <6 ft height. A local buddy on mine has a large V2 with 50mm stem at states perfect fit and he is exactly 6' with longer torso than legs.

    BTW, I just ordered my V2 from Trident today! Went medium even though I am closer to 5'10" w/shoes w/long legs for my height. Plan to run 50mm stem, if went large I would definitely have to run 30-35mm tops. Could of went either way with sizing, but chose the medium for shorter wheelbase as I primarily ride where not much open terrain.
    Ride On!

  9. #9
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    Quote Originally Posted by tomasis View Post
    interesting to hear that it doesnt affect climbing. Good point about wider handlebar balancing up twitchier handling caused by shorter stem.
    Remember, if you go with a shorter stem for cockpit sizing, but then get wider bars too, that will effectively relengthen the cockpit to some extent. I run a 30 mm megaforce 2 stem on my blindside, I was stuck between a small and a medium and decided to go for a medium and the shortest possible (non-mondraker) stem. I think it feels great; I dont notice it being "too" twitchy and the longer front-center feels so stable in almost all situations. Even in turns; no problems weighting the front wheel. Just takes a little adjusting. In my humble opinion, stem length choice should be mostly for the cockpit length (and handlebar width, which affects stem length choice) that works best for you, with the shortest stem/longest bike possible;...not for a certain "steering feel"
    On my med Butcher which is a shorter bike i run a 50 mm stem and both bikes have almost the same cockpit length and the same bar width.. When I switch from one to the other seems like I istantly adjsut and cant really feel too much difference between them steering-wise except of course that the blindside is slacker and longer travel and i usually ride steeper trails on it. That being said, Im talking about handling differences among a small range of shortish stems (30-55 mm) being not a big deal...of course between a 30mm and a 90 mm will steer very different, but IMO on modern aggressive bikes if youre running anything over 60 mm to feel right you're on too small of a frame, or your bars are too narrow.
    Last edited by dwyooaj; 12-20-2012 at 11:13 PM.
    '14 rocky mountain altitude, rally edition
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  10. #10
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    Quote Originally Posted by tomasis View Post
    hey

    Im curious if any of you have experience running 30mm and 50mm stems and compare differences? What brands do sell such short stems?

    Im 5"10 (177cm) and planing a bit larger frames than normally suited for me. With 30mm stems reach will be good but I get curious what kind of challenges one gets with such short stem? Especially climbing, cornering. I assume that on downhill it makes more stable due longer TT/WB.

    I also have DH rig and may switch to larger frame and short stem as well.

    If there is no large difference, then I may switch to short stem.

    I have liked the 30mm syntace, compared to a 45mm. I noticed the 30mm was a bit better going around really slow switchbacks- the longer stem got pushed around more mid corner when hitting a bump. I think this is more noticeable with a slacker head angle.

    Downside to the 30mm is going to be if you can't get it low enough on the larger frame and the front end doesn't have enough weight on it. Then it won't corner well. I think that is a problem for short riders like me.

  11. #11
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    Also, its a good idea to figure out from a previous bike what overall cockpit length works well for you: reach( not top tube length!) plus stem length; then if you know the reach of a frame you want to get you can at least approximate what stem length would work with what frame size; helps with frame size selection. Other factors play into the overall reach calculation as well, such a stem rise bar rise, stem stack height, spacers under stem, bar rise, head tube length, bottom bracket height, and head tube angle, but usually frame reach plus stem length gets you in the ball park between frames that are about the same travel, fork length, head angle, intended use, etc. Besides, noone will notice a difference of a few millimeters. i actually have come up with a complicated formula that takes it all into account all of the above. Maybe ill post it up when im less lazy.
    '14 rocky mountain altitude, rally edition
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  12. #12
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    OK heres the full formula for cockpit length, which I call "full reach". A few definitions first:

    reach: horizontal distance from center of BB to top center of HT. Make sure you know this (and your HA) accurately with your fork length.
    Stack: Vertical distance from BB to top cntr of HT
    "Steerer stack": Height of top headset cup + spacers + 1/2 of stem stack height.
    HA= head angle.

    Full reach= Reach - (cos HA x steerer stack)+ (sin HA x stemLength)- (cosHA x bar rise)

    Notice I left out bar width and backsweep. I did this for simplicitys sake, as I always use the same bars. Most bar's backsweeps are close enough not to matter, and most riders will use similar bar width on whatever bike. Besides, you can fine-tune reach by rotating bars backwards and forwards.

    Next up, the formula for "full stack" (verical distance between BB amd bars) which one will usually also want to keep the same between bikes (perhaps)

    full stack = stack + (sin ha x steerer stack) + (cos {HA-stem angle} x stem length)+ (sin HA x bar height)

    Nerdy enough?
    '14 rocky mountain altitude, rally edition
    '11 transition blindside

  13. #13
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    Quote Originally Posted by jgusta View Post
    I don't know, afraid it would be a major distraction..the tit that is
    certainly wouldnt mind the otb crashes anymore though.

  14. #14
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    I recently purchased a 35mm Spank Spike Race stem that I installed on my 5in travel AM / trailbike. The stem placed my handlebar slightly behind the dropouts on my fork causing the front end to push when the suspension should have been working while hitting turns. In fact, the fork performed like it needed to be rebuilt due to a lack of weight on the front end.

    The stock 85mm stem was little bit too long for my purposes. I ended up with a 50mm Kore B 52 that placed the bars just in front of the dropouts while still giving me the snappy handling I was after.

    Many mailorder companies will take a stem back if it turns out to not suit your needs without too much of a hassle.

  15. #15
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    Quote Originally Posted by Nandus View Post
    I recently purchased a 35mm Spank Spike Race stem that I installed on my 5in travel AM / trailbike. The stem placed my handlebar slightly behind the dropouts on my fork causing the front end to push when the suspension should have been working while hitting turns. In fact, the fork performed like it needed to be rebuilt due to a lack of weight on the front end.

    The stock 85mm stem was little bit too long for my purposes. I ended up with a 50mm Kore B 52 that placed the bars just in front of the dropouts while still giving me the snappy handling I was after.

    Many mailorder companies will take a stem back if it turns out to not suit your needs without too much of a hassle.
    hmmm, thats a very interesting observation. did you try to adjust your fork differently?

  16. #16
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    I have a 30mm (kind of generic thing, manufacturer escapes me) on my medium SX trail. I also have 30 inch chromag bars. I'm 5'11" and I use this bike for lift access, shuttles and pedal ups. I think it works fine for climbing but really shines for descending. I should add I usually don't pedal up super steep trails/roads, rather save energy for the descent.....anyhow Specialized specced 30mm stems on a few of their gravity bikes a few years ago, not sure if they still do but obviously it worked for them. I'm currently putting together a 2011 enduro and will use same cockpit set-up as the SX for it. Its comfortable and lets me get rowdy on the downhills.

  17. #17
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    I ended up getting a large frame on my bike and putting the shorter stem. Feels great.

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