Best AM Stem Size

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  • 11-22-2012
    guitarjohn21
    Best AM Stem Size
    I'm thinking of going shorter. Running a 70mm now and don't like the transition from my DH (which is 50mm) back to AM every time I switch bikes. Feels kinda squirrely for a while until I get used to it again, like the old 110mm. Anyone running shorter stems on AM?
  • 11-22-2012
    mlouro
    Plenty of people do, I use a 50mm one and everyone I know who switched to 50mm has been happy with it.
  • 11-22-2012
    gurp
    50-70mm is normal. I've ridden with a 50mm for years now. My lower back feels it a bit on the climbs, but it's worth it on the descents.
  • 11-22-2012
    Hoban
    I'm not sure the extra 20 mm will make a huge difference, it may just be the steeper head angle.
  • 11-22-2012
    guitarjohn21
    Good point, Its probably a combo of both...
  • 11-22-2012
    dump
    Give it a go. Whatever feels best frankly. 50mm feels great on my current bikes.
  • 11-22-2012
    006_007
    It cant hurt to try it at least. If possible "borrow" the 50mm stem from your DH bike before laying out the cash on the AM bike. Maybe try the DH bikes wider bars (if applicable)
  • 11-22-2012
    beebee5
    How do you guys like the 50mm climb? Is it more difficult compared to a longer stem?
  • 11-23-2012
    dropadrop
    Quote:

    Originally Posted by beebee5 View Post
    How do you guys like the 50mm climb? Is it more difficult compared to a longer stem?

    A longer stem will put your weight forward, but it's just one small piece of the equation that also includes the rise of the stem, bar width and rise, spacers below the stem and for A2C.
  • 11-23-2012
    mlouro
    Quote:

    Originally Posted by beebee5 View Post
    How do you guys like the 50mm climb? Is it more difficult compared to a longer stem?

    I still do some steep climbs with the 50mm stem and don't have any problems keeping the front wheel down. I do have 730mm bars and a coil lyrik up-front thou :D
  • 11-23-2012
    DAVID J
    I'm a recent convert to the short and wide set-up. Went from 660/90 to 720/60. Started with a 40mm stem,wasn't bad but a bit tight. Climbing is still good,just a slight adjustment in body position. My fingers and shoulders are taking some licks with the wider bars.
  • 11-23-2012
    Zen Cyclery
    Quote:

    Originally Posted by beebee5 View Post
    How do you guys like the 50mm climb? Is it more difficult compared to a longer stem?

    Well stem length is only one out of a multitude of factors that will effect handling.
    But a shorter stem will take a bit more weight off the bars. For inexperienced riders, this can cause the front wheel to slip out a bit more often than what would be considered ideal.

    Overall though, I like the feel of a shorter stem (I run 70mm). I think it quickens up the handling a bit, and it makes me feel a bit more confident when descending particularly on the steep stuff.
  • 11-24-2012
    Jwind
    I'm a fan of a bigger frame for stability in the chunk and short wide bars. 750mm/45mm I'd go wider if I didn't start to wack stuff.
  • 11-25-2012
    retrofred
    Well I go between a 50mm and a 60mm stem depending on the bars I run. Currently I am happy with a 60mm stem and a 745mm bar combo.

    Sent from my SGH-T889 using Tapatalk 2
  • 11-25-2012
    beebee5
    Just ordered a 40mm stem with answer pro taper 720 am for my mountain cycle ht
  • 11-29-2012
    Oscar Hinde
    I put a 50mm Thomson two weeks ago. I used to have an 80mm stem. I'm LOVING the 50mm.
  • 11-29-2012
    MTBerNick
    Im about to order some 760mm bars, I already have a 70mm stem with some 620mm bars.
  • 11-29-2012
    ATX_fix
    got a 50mm stem and 760mm bars on my rig.
  • 11-29-2012
    Crash-VR
    First ride on my Nomad with 750mm bars and 60mm stem on my Nomad. I love it. I sit up straighter and the width slows things down. It's funny how the world of bikes is a balancing act of mm's and oz.'s...
  • 11-30-2012
    Hollyw00d
    Quote:

    Originally Posted by Hoban View Post
    I'm not sure the extra 20 mm will make a huge difference, it may just be the steeper head angle.

    huge difference. very noticeable. when I went from 45mm to 35mm stem I could tell quite a bit.
  • 11-30-2012
    Hollyw00d
    I went from a 90mm stem and 680mm bars to a 35mm stem and 780 bars. I absolutely love it.

    On fast flowy singletrack it can get so sensitive that it's almost twitchy, but I love it.

    I can climb steep without issue I just gotta remember to keep my weight forward on the steep parts.
  • 11-30-2012
    ATX_fix
    I love my wide bars, but there's been a few times where the tree squeeze has got me!
  • 11-30-2012
    Hollyw00d
    Quote:

    Originally Posted by ATX_fix View Post
    I love my wide bars, but there's been a few times where the tree squeeze has got me!

    There are tight spots, but I have yet to find one that I can't get thru.... just gotta be vigilant about your line (which ideally you should be anyway..)

    :thumbsup:
  • 12-01-2012
    beebee5
    Jus took a spin for the first time on the trails with the 720 AM protapers with the new short stem. It does make a very big difference. The confidence on descending has went up. As for going up it lifts the wheel off the ground a bit.
  • 12-01-2012
    miniwisejosh
    I used to have a 50mm stem. Now it's 35mm, and I'm pretty happy with it.
  • 12-01-2012
    Scott@GO-RIDE.com
    For me there are three things that come into play when deciding on stem length.
    1. Length is obivously based on rider size and how closely the ETT length of your bike matches your body.
    2. The style of riding you prefer. In this case it is All Mountain. For DH/FR I'd go shorter and for XC I'd go longer.
    3. The width of your bars. Generally, wider bars add ot the reach of a bike and require a shorter stem.

    For me 70mm is common for my AM bikes, but I'll go as short as 50 when the TT is unusually long such as with the Yeti SB66 that is 1" longer than many other bikes of the same size. For my DH bikes I've alwasy used 50mm. For my XC bikes I still like it a bit shorter and won't go longer than a 90mm.
  • 12-01-2012
    IAmHolland
    Quote:

    Originally Posted by Scott@GO-RIDE.com View Post
    For me there are three things that come into play when deciding on stem length.
    1. Length is obivously based on rider size and how closely the ETT length of your bike matches your body.
    2. The style of riding you prefer. In this case it is All Mountain. For DH/FR I'd go shorter and for XC I'd go longer.
    3. The width of your bars. Generally, wider bars add ot the reach of a bike and require a shorter stem.

    For me 70mm is common for my AM bikes, but I'll go as short as 50 when the TT is unusually long such as with the Yeti SB66 that is 1" longer than many other bikes of the same size. For my DH bikes I've alwasy used 50mm. For my XC bikes I still like it a bit shorter and won't go longer than a 90mm.

    What he said, except I tend to buy my frames now to run around 50, so I would go larger on the frame if I could.

    So, on my 6" AM bike I run a 65mm stem with a 23in ETT and 71 SA. My 5" Trail bike, I run a 40mm stem with a 24in ETT and 72 SA. My AM HT, I run a 50mm stem with a 23.5in ETT with a 72 SA. All have 780mm bars. My trail bike is my latest addition, I like the fit so far with a bit more reach. It depends on the reach measurement, which is affected by the seat angle and the ETT.
  • 12-06-2012
    LaXCarp
    My AM bike is currently running 75mm x 690mm but I've wanted to change it all summer ( I need to get a new fork to run a shorter stem, maverick duc). I am planning on going 45-50x715. I have been riding my gf's downhill bike (knolly delirium) as a trail bike the last couple weeks and I have loved the attitude of the short front end.

    I think the word "twitchy" has a negative conotation to it and isn't accurate. First of all, I dont steer by turning the handle bars, I turn by leaning the bike over and that is much easier with wider bars. I have found that the quickness of the short stem allows for split second manuevers to avoid obstacles while maintaining my overall desired path of direction. These types of manuevers simply aren't feasible with a longer stem. If you have fast reflexes, this will definitely benefit your ride.

    I havent had any problem keeping the front end down on climbs...I normally climb standing up so I just keep my shoulders over the stem and it is plenty well weighted. A benefit of the light front end is that it's easy to keep the bike in a nearly lofted position while riding making it much easier to place the front end where you want it over rocks/roots etc. A little pedal jab is all it takes to get the front end up and over and put it down where i want it.
  • 12-13-2012
    beebee5
    double post
  • 12-13-2012
    beebee5

  • 12-13-2012
    MTBerNick
    I just slapped on a 50mm stem and some 760mm bars. They are WIDE, im going to chop them down to 700.
  • 12-14-2012
    trmn8er
    Good thread. Replaced my 110 with an 80. I have a long reach, and the 30 mm difference makes the bike feel WAY better. Probably could have gone with a 60 or 70...
  • 12-15-2012
    guitarjohn21
    So I'm running 685mm with a 70 mm stem now. Going to try 730mm and 50mm and see if I like it. Going with something similar on my DH rig, maybe 750. I've seen the 820mm's as think, Way to drastic of a change in one leap for me.

    Are their limits for bar width in Enduro racing? It was 29 7/8" when I was racing BMX as a kid. (or, under 30" if I remember correctly)
  • 12-18-2012
    LaXCarp
    Hey Nick,

    Don't chop them down to 700 right away. I would do it in increments. Maybe go 740 then 720 etc to see what you like. For my size (5'7") i am finding the sweet spot to be at 715 or so
  • 12-20-2012
    D3NN15M
    Planning to go with either a 750 or 711 mm bar, with a 50-65mm stem. Coming from a 620/90, is this too much or will I get used to it eventually?
  • 12-20-2012
    gurp
    When changing bar size and you don't know what you're going to like yet

    - Get something wider then you think you need
    - Use lock on grips. Start with the grips/controls at the ends of the bars and get at least a few hours of riding in on that setup, making sure to tackle a mix of terrain: wide open high speed, narrow and technical, and super chunder.
    - If it feels too wide, bring the grips in 5mm in on each side and retest.
    - Repeat as necessary.
    - Once you find the right width, cut the bars down.
  • 12-20-2012
    D3NN15M
    Good tip gurp, thanks. Already have a lock on grip so that takes care of one thing. Just need to find out if cutting a havoc carbon bar will void its warranty.
  • 12-21-2012
    mlouro
    mtngt, it won't, the havoc carbon actually has cut marks up to 710mm.
  • 12-29-2012
    pastajet
    Quote:

    Originally Posted by Scott@GO-RIDE.com View Post
    For me there are three things that come into play when deciding on stem length.
    1. Length is obivously based on rider size and how closely the ETT length of your bike matches your body.
    2. The style of riding you prefer. In this case it is All Mountain. For DH/FR I'd go shorter and for XC I'd go longer.
    3. The width of your bars. Generally, wider bars add ot the reach of a bike and require a shorter stem.

    For me 70mm is common for my AM bikes, but I'll go as short as 50 when the TT is unusually long such as with the Yeti SB66 that is 1" longer than many other bikes of the same size. For my DH bikes I've alwasy used 50mm. For my XC bikes I still like it a bit shorter and won't go longer than a 90mm.

    Wow, brilliant stuff, getting tired of the 'you have to go with 50 for a modern bike' attitude. I like 80 on my med Mojo HD, I am 5'9" and like the slight reach. Yes, I have played with stem, bars, headset stack, forks, shocks, angleset, etc., and always come back to my comfortable 80 (for me), and I ride everything, from sick steep XC trails on the HD.
  • 12-29-2012
    ATXZJ
    I have a long torso and arms and have been running a longer stem which sucks on an AM rig. I yanked the 120x680 stem and bars and added a 60x765 and couldn't be happier.

  • 12-30-2012
    saturnine
    i alternate between 50/711 and 70/711. i'm not sure which i prefer.
  • 12-31-2012
    Tulok
    I had a 24" x 110 setup on my xc bike, it felt awful! then I switched to a 26x90, it felt awful! (a little better).
    So I went back to my AM bike with the 70mm stem and 670mm bars, and it feels good, but my weight is too far back and it washes out on flatter turns.
    So I ordered a new 70mm stem and 740mm bars and I'm gonna throw the 670/70 combo on my DJ bike.

    Wider feels better! but the biggest factor is still bike-fit IMO.

    oh yeah, and the XC bike is put away for good. lol
  • 01-03-2013
    moshelove
    I'm 6'1" on a medium reign. A little short for me. I've been running 680mm bars and a 60mm stem forever. 70mm have up too much on the DH control.

    I recently got a pair of 745mm bars and moved down 10mm to a 50mm stem. The difference in control was astounding.

    I achieved basically the same reach forward, but have moved the weight distribution farther behind the front axle. The improvement in control is so much better, that I was able to drop tire size and still have the same if not better steering control. All while having a much faster rolling bike.

    Wider bar and shorter stem has been by far the biggest improvement since a KSi900 remote and a fox 36.

    Going into corners now with so much more confidence. Just setting the line and letting the bike do all the work. Huge leverage advantage. I will never go back to narrower bars and or compromise descending confidence and control with a longer stem. A must try for everyone with a longer stem.


    If you need anything I'm Fabian, if not, I'm Dale
    .
  • 01-09-2013
    max1131
    Quote:

    Originally Posted by Stripes View Post
    Yes, but run wider bars too.
    Shorter stem = twitchier handling
    Longer stem = slower handling

    Wide bar = slower handling
    Narrow bar = twitchier handling

    So make sure it balances out. For me, 29" bars and 50mm stems seem to be the magic number on all my bikes.

    I agree, the trick on this is finding the combination of these 2 lengths. Another important factor is the sizing of the bike and how it feels. If its a bit too long, you def have to go with a shorter stem, if too short, maybe a longer stem. Either or, the majority (me included) are running 50-60mm stems with 720-750mm bars. Seems to fit most of us out there.
  • 04-01-2013
    guitarjohn21
    So I wound up with a 45mm stem and 800mm Enve carbon bars on my AM and it is absolutely the best improvement I've made. The steering is more precise and the stability on DH is just awesome. The extra leverage you gain helps with bunny-hopping over obstacles and jumping, it feels like a big BMX bike now! With bars that wide and a short stem, it still climbs the steep stuff just as well, to my surprise.
    They also have a 9 degree backsweep so your wrists are in a better position for that width. Now, I've seen a few sections of trail that I have to slow down a bit to avoid hitting branches, but the trade off is worth it. The fun-factor gained from this improvement is priceless.

    I put this same set up on my AM and DH bikes and couldn't be more pleased.
  • 10-02-2013
    OMNICELLL
    My idea is to switch to XC riding using my reign xs...

    Im using 50mm atlas with 30inch race face am bar! works with the seat up, However, not what Im looking for in general when XC'ing.

    Ive decided to go with a flat bar and a Salsa promoto 2 110 -25 degree. This brings about a great expansion for xc riding. However, you always have to switch out the bar/stem combo whenever going to the riding area! not a problem I think!
  • 10-02-2013
    Scott_PA
    740mm wide riser var with a 70mm zero rise stem. Feels good to me so far.
  • 10-02-2013
    tiltedworld
    I just made this transition as well going from stock 690mm/70mm combo to an Answer Carbon Protaper 720mm/ Answer DJ 50mm stem combo.

    I read this article in prior to purchase that helped me decide on a ratio Mountain Bike Handlebars: The Width Issue - BikeRadar

    I am loving the combo so far - more control on the downhills and no ill-effects on the climbs. If anything I think the slightly shorter cockpit is helping my climbing because I seem to keep my arms bent more and gets my upper body in a better climbing position.

    I liked the combo so much I swapped my old 690mm/70mm combo onto my wifes bike (who is a rank beginner) which had a 620mm/90mm combo and she immediately felt better and more confident / in control in all situations.
  • 10-03-2013
    Jwind
    Quote:

    Originally Posted by Jwind View Post
    I'm a fan of a bigger frame for stability in the chunk and short wide bars. 750mm/45mm I'd go wider if I didn't start to wack stuff.

    Update! 820 bars! Even better!
  • 10-17-2013
    hentaiboy
    Quote:

    Originally Posted by Jwind View Post
    Update! 820 bars! Even better!

    This is getting ridiculous. Next everyone will be running 1 metre wide bars with 10 mm stems :eekster: