Forum home Mountain biking forum MTB general

Sizing Stem Choice....

SignumSignum Posts: 8
edited June 2015 in MTB general
Hi

New to the forum, and looking for a bit of help if possible, no doubt this question has been asked many times, so sorry to repeat.
Have been riding for a few years, just casual mind you on some local trails and I really should ride more.
Anyhow, I have a 2012 Specialized Rockhopper, one thing I have always found is it feels too low on the front, I tried to look at solving this last year, went to a bike shop who had a Specialized Geometry stem to help my set up, this didn't work out too good and was pretty much told there wasn't much options.

In my head I see bringing the angle of the stem up the ideal solution, but I couldn't find a lot when I last looked, other than adjustable stems.
Picking this up again I see the Easton EA70 stem which they do a 17 degree rise in, against the 7 degree rise of my current stem, this sounds ideal.

So my question is what length do I go for, I have a 19" frame, I am 6ft and the bike feels good, quite nimble, I do seem to have slightly shorter arms for 6ft, with my seat centre on the rails, elbow on the nose, my fingers just touch the steerer :oops:
So I'm floating between 70mm or 90mm in a 17 degree rise, any help, tips or hints would be appreciated,

Mark

Posts

  • BloggingFitBloggingFit Posts: 919
    I would go shorter but not necessarily higher. Shorted stem will bring you more upright and less stretched out while going higher will lift your weight more off the front end which can make the front end lighter and cause front tyre grip issues.

    I would go with a 50mm zero degree rise stem if it were me but another option is to buy a couple of different cheap £10 options on eBay and then buy a more quality stem once you are happy with a size.
    Bird Aeris : Trek Remedy 9.9 29er : Trek Procaliber 9.8 SL
  • SignumSignum Posts: 8
    ...... another option is to buy a couple of different cheap £10 options on eBay and then buy a more quality stem once you are happy with a size.

    Not a bad idea I guess....would a really short stem not make the front end feel a bit twitchy? I can't remember what is on there, I did measure it once, 90mm maybe....will need to get the tape out.

    I get a couple of discomforts after about 8 miles plus, but the main one is my wrist's , tried rolling the bars, adjusting the controls slightly but hence the feeling I want to come up a touch, almost as though I am putting too much weight on my wrists..

    A friend I ride with has a Hardrock, from the same year, and that came with a much higher rise stem (20 degrees I think) and when I have had a blast on that, although a 21" it does sit a bit better. Unfortunately they only have 25.4 clamp so I can't try on my bike :(
  • kajjalkajjal Posts: 3,380
    You can by adjustable stems to move around until you get it right and then buy the correct fixed stem if you like.

    What size is the drop from the saddle to the bars ?
  • SignumSignum Posts: 8
    Kajjal wrote:
    What size is the drop from the saddle to the bars ?

    Do you mean the height from the ground to the seat, and the height from the ground to the bars and what this difference is?
  • kajjalkajjal Posts: 3,380
    Signum wrote:
    Kajjal wrote:
    What size is the drop from the saddle to the bars ?

    Do you mean the height from the ground to the seat, and the height from the ground to the bars and what this difference is?

    Just measure the vertical distance between the top of the saddle and the top of your bars.
  • RockmonkeySCRockmonkeySC Posts: 15,247
    Go shorter rather than higher. Raising the bars will have a negative effect on handling, grip and your feel for the front end.
    Drop from saddle to bars is meaningless.
  • kajjalkajjal Posts: 3,380
    Go shorter rather than higher. Raising the bars will have a negative effect on handling, grip and your feel for the front end.
    Drop from saddle to bars is meaningless.

    Strange you say drop is meaningless after first saying raising the bars will have a negative effect on handling , grip and feel. It depends how low or high the bars are to begin with relative to the saddle unless you purely ride downhill.
  • RockmonkeySCRockmonkeySC Posts: 15,247
    You shouldn't be in the saddle when cornering with any real aggression anyway so your seated position is irrelevant to cornering grip or handling during technical riding.
  • SignumSignum Posts: 8
    Thanks for the replies gent's all good info so appreciate it.

    I had a measure, from the ground to the top of me seat is about 102cm, the same measurement to the top of the bars (hand position as they are a riser bar) 110cm, so looking about 80mm difference. (the stem is about 102cm, but the riser bar pushes it up slightly)

    I do agree that when cornering, or on small technical sections, you are right I am out of the saddle, but some of my local trails have some fire tracks in, which I don't mind, it's at this point I am in the saddle and the weight on my wrists (or angle) is where I start to feel it.

    I also checked and stem is 90mm with 7 degree rise.....so based on the good info I have had so far;

    - is 80mm difference between seat and bars not enough, for the times when I am in the saddle

    - will going from 90mm to 70mm make much difference, I can see it bringing me up slightly on my back, but will I still have more weight over the front and in turn, more weight on my lower arms, hands etc, which is where I am having the issue?

    Thanks again for all the help.
  • The RookieThe Rookie Posts: 27,748
    Those bars are pretty high, for that sort of riding most people will have the grips at close to or even below the saddle height, it's possible the reach is too long, alternatively the alignment of the grip section is such that it is twisting your wrists in or out, have a look at that, you can try rolling the riser bars forward or back in the stem clamp.

    A side on photo of you on the bike would help.
  • vanameesvanamees Posts: 74
    Your bars are 80 - 100 mm too high.
  • RockmonkeySCRockmonkeySC Posts: 15,247
    vanamees wrote:
    Your bars are 80 - 100 mm too high.

    Couldn't his saddle be too low? It's going to be difficult to adjust bar height by 80mm
  • Clockworkmark31Clockworkmark31 Posts: 1,053
    evening all,

    don't want to hijack the op's thread, but having read some of the comments on seat and bar height I have heard of this before but not understood it.

    From the ground to the top of my seat is 102cm and from the ground to the top of my grips is 110cm, is there an ideal range they should be in or is my setup to whack?
  • cooldadcooldad Posts: 32,601
    If it feels right it's OK.
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

    London Calling on Facebook

    Parktools
  • RockmonkeySCRockmonkeySC Posts: 15,247
    There is no ideal set up. There is no correct relationship between saddle and bar height.
    If you are short and ride a bike with 160mm forks then your bars will probably be higher than your saddle even if you have flat bars and no stem spacers.
  • SignumSignum Posts: 8
    The Rookie wrote:
    A side on photo of you on the bike would help.

    Thanks for the input, I will get a picture now we are home.

    vanamees wrote:
    Your bars are 80 - 100 mm too high.
    Couldn't his saddle be too low? It's going to be difficult to adjust bar height by 80mm

    ...again thanks for the post's, it all helps. Surely they cant be 100mm to high? I am 6ft (ish), I have about a 33" inside leg, and I am on a 19" bike. a 17" would have been way too small, I can't take 4" off the front and if I raise the seat 4" higher I won't be able to reach the pedal, let alone turn it lol :D

    I will see if I can get a pic to see where we are.
  • Clockworkmark31Clockworkmark31 Posts: 1,053
    cooldad wrote:
    If it feels right it's OK.

    Doesn't quite feel right, saddle height feels good but steering feels vague. Asked in buying advice as want to change this and MBR did a review of my bike and mentioned the same faults that I am complaining about. The advice given in the buying section was to check saddle and bar height etc.

    Hadn't heard of it before and still don't understand it. Was just wanting some more info as the op has been given similar advice.

    Wanting to purchase some renthal fatbar carbon lite and the apex stem. The cost of these means no experimenting. So just want more of an explanation so I can make an informed decision rather than just buying a 50mm stem with a 10 or 20 degree riser without understanding why. Must be some black magic to it all rather than get what feels right.
  • Antm81Antm81 Posts: 1,406
    cooldad wrote:
    If it feels right it's OK.

    Doesn't quite feel right, saddle height feels good but steering feels vague. Asked in buying advice as want to change this and MBR did a review of my bike and mentioned the same faults that I am complaining about. The advice given in the buying section was to check saddle and bar height etc.

    Hadn't heard of it before and still don't understand it. Was just wanting some more info as the op has been given similar advice.

    Wanting to purchase some renthal fatbar carbon lite and the apex stem. The cost of these means no experimenting. So just want more of an explanation so I can make an informed decision rather than just buying a 50mm stem with a 10 or 20 degree riser without understanding why. Must be some black magic to it all rather than get what feels right.

    Pick up some cheap bars and stems from the classifieds or eBay to experiment with, you'll likely be able to sell them again for the price you paid and then you can get a decent one that gives you what you want without the risk.
  • Clockworkmark31Clockworkmark31 Posts: 1,053
    Bars I need to go wider mine are currently 690mm and it is too narrow. Current stem is 100mm +-8 I have a spare stem 70mm +7 and the apex I am thinking of buying is the 50mm that is +-6. How my head hurts, if this was electronics you have formulas to work out the variables.

    Why is this not the case with bikes haha
  • Clockworkmark31Clockworkmark31 Posts: 1,053
    Bars I need to go wider mine are currently 690mm and it is too narrow. Current stem is 100mm +-8 I have a spare stem 70mm +7 and the apex I am thinking of buying is the 50mm that is +-6. How my head hurts, if this was electronics you have formulas to work out the variables.

    Why is this not the case with bikes haha

    Now understand why my college tutor used to call me tangent.......oh well
  • SignumSignum Posts: 8
    From the ground to the top of my seat is 102cm and from the ground to the top of my grips is 110cm, is there an ideal range they should be in or is my setup to whack?

    ....pretty much the same as mine.

    So I have got a picture up, I have added some coloured lines to my wrist, the purple line is the current angle, and where I get discomfort after a while riding.
    In my head, and as per my original question, I thought if I took the bars a touch higher, I would relax the angle to the blue line and take some strain off my wrist slightly..however looking at some of the replies, I don't want to be taking the front any higher, so unsure now?!

    Does this help at all? Thanks

  • kajjalkajjal Posts: 3,380
    Simple change is to move the spacers above the stem and see how it feels on a quick test ride. This will drop the bar and can easily be put back the way it was.

    A very simple way to measure drop assuming your saddle is level is just rest a broom handle or similar on the saddle and see the difference to the bars. Most mountain bikes tend to be about level with xc riders being a little more below. Its what feels best for you that matters. Some road bikers have the bars much lower but for mountain biking this tends to upset the bikes handling too much and shift the riders weight too far.
  • Clockworkmark31Clockworkmark31 Posts: 1,053
    Going to have a word with the senior and test engineers tomorrow, and see if they can do an XYZ drawing of me on the current setup and then have parameters changed to see how my posture would change before I shed any money out.

    Maybe what I think is a good setup is whack. But I will have a 3d drawing to play around with. Lots of buying coffee for me tomorrow
  • SignumSignum Posts: 8
    Kajjal wrote:
    Simple change is to move the spacers above the stem and see how it feels on a quick test ride. This will drop the bar and can easily be put back the way it was.

    Not a bad idea, I think a tweak of the breaks and shifters may help too - so having looked at the picture, do people think a shorter stem will help?

    Cheers
  • cooldadcooldad Posts: 32,601
    If anything I would say a longer one.
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

    London Calling on Facebook

    Parktools
  • Clockworkmark31Clockworkmark31 Posts: 1,053
    As an experiment I flipped my stem over so it is now -8 degrees steering felt a lot better but after a short ride was getting pain in my hands more notably minimi muscle had to google it. Guessing from having looked at how my bars are now I can see why. See picture.

    DSC_0171_zpsd2icnmo7.jpg

    Do I need to roll the bars toward me or away from me? Also if my stem is now -8 degrees rather than plus 8, and if I need to bring the bars toward me (i think I do) how would that help me determine what stem and bar rise to get?

    Thanks and sorry to the OP for jumping on your thread but two birds one stone.
Sign In or Register to comment.