# How to determine best stem length?



## pmg5727 (May 10, 2009)

Still have the stock stem on my new bike which may be a tad too long. I think the stem is 110mm, but I am not sure which landmarks I measure from to determine this. I would like to try a shorter stem to improve steering control and jumping ability but I am not sure how much smaller I should go. The bike is an all-mountain variety bike sometimes used for light downhill riding. Any ideas would be greatly appreciated.


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## AZ (Apr 14, 2009)

Take your bike to LBS , try a few out . :thumbsup:


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## PrincipalRider (Jun 24, 2005)

AZ.MTNS said:


> Take your bike to LBS , try a few out . :thumbsup:


 That is actually not bad advice. Everyone has different preferences. For XC stuff, feeling a little spread out feels good to me. But for my AM bike, I ride with a 65 mm stem given that I want the thing to turn sharper and I also find it is easier to get the front end up with a shorter stem. Try a few out and see how the effect your seat position, where your shoulders sit, how far your back goes, that kind of suff.

Shorter stem means a little more comfort and a more upright riding position as well, but it is at the expense of some bio-mechanical efficiency. It all depends on what is important to you and what feels good.


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## NeverFree (Nov 8, 2009)

pmg5727 said:


> Still have the stock stem on my new bike which may be a tad too long. I think the stem is 110mm, but I am not sure which landmarks I measure from to determine this. I would like to try a shorter stem to improve steering control and jumping ability but I am not sure how much smaller I should go. The bike is an all-mountain variety bike sometimes used for light downhill riding. Any ideas would be greatly appreciated.


how can you expect useful information when you give so little yourself....

take it to lbs is the best.

you want advice on sizing and the only thing you give is the size the stem is.

stem length is measured from centre of steerer tube to centre of bar clamp.

how about we get some more info...

your height
bike model/year
bike size
actual stem length

you can add your arm length as well if you want. how do you feel on the bike too stretched out?


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## pmg5727 (May 10, 2009)

The bike is a Giant Reign X1 (2009) Medium. I am 5-7 in height. The bike is supposed to fit anyone who is 5-6 to 5-11 range so I am guessing the stock stem is too short.

What landmarks should I use to measure my arm length and should my arms be fully extended when I do so? 

I don't particularly feel like I am too stretched out especially when compared to my XC bike, i feel more upright & comfortable relative to that bike. 

Unfortunately the LBS that I bought the bike from never fitted me properly on the bike, I think they were trying to make a quick sell. One of the kids working there was about my same height and he set up the bike to his specifications. 

When I use the landmarks you provided for the stem it appears to be 70mm, but I'm still not sure if I'm measuring it properly.


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## Bigrocks (May 14, 2004)

I would try a 90mm which is good midway point.


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## vikingboy (Nov 5, 2008)

i just bought a bunch of stems and tried them all over a few weeks. I sold the ones I didnt want for close to what I paid for them as they were as new. I dont have a good LBS, YMMV.

good luck


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## Ken in KC (Jan 12, 2004)

*My thoughts...*



pmg5727 said:


> The bike is a Giant Reign X1 (2009) Medium. I am 5-7 in height. The bike is supposed to fit anyone who is 5-6 to 5-11 range so I am guessing the stock stem is too short.
> 
> What landmarks should I use to measure my arm length and should my arms be fully extended when I do so?
> 
> ...


If you ride with others or belong to a club, people will have extra stems. Ask to borrow several different lengths and ride with them on the trails. Once you've deteremined the correct length and rise for you, buy a stem.


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## AndrwSwitch (Nov 8, 2007)

Ken in KC said:


> If you ride with others or belong to a club, people will have extra stems. Ask to borrow several different lengths and ride with them on the trails. Once you've deteremined the correct length and rise for you, buy a stem.


+1. It's really something you have to figure out by feel. On a mountain bike, I wouldn't trust a pro fit to get me the right stem length, since you can't tell how it will handle until you're on trails.

70mm is much more likely the length of stem you have. 110mm would be a very long stem for a stock mountain bike lately, especially on all but the largest sizes of bike.

It might be hard for you to get a shorter stem, unless it's BMX-style. Road/MTB style stems have a minimum length in order to be shaped the way they are and clamp both the bars and the steer tube securely, and a lot of brands go no shorter than 65mm.

If you do go shorter, you're likely to have a more upright posture and an easier time wheelie-ing your bike. You may also start having problems keeping the front wheel down and tracking well on climbs, and depending on the style of handlebars you prefer, it may be harder for you to keep a good line in general.


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## NeverFree (Nov 8, 2009)

pmg5727 said:


> The bike is a Giant Reign X1 (2009) Medium. I am 5-7 in height. The bike is supposed to fit anyone who is 5-6 to 5-11 range so I am guessing the stock stem is too short.
> 
> What landmarks should I use to measure my arm length and should my arms be fully extended when I do so?
> 
> ...


You don't need some smoke and mirrors bike fit. the other main thing is if its a new bike and a new style of bike to you whats to fit? the main goal once the sizing up has been done, which for 5'7" the medium is good, is now to ride the bike and get a feel for it and how comfortable you are.

if while riding it you find you are uncomfortable then its time to start changing things, don't change things before you ride the bike.

if you feel stretched on descents or if you are having a feeling of too much weight over your front end you can switch to a shorter stem 50, 60, 65, but your climbing will suffer.

Ignore what andrwswitch mentioned about stem length availability..

it all depends on your riding style and how much climbing vs descending. a shorter stem will also speed up your steering.

At the end of the day though, you should be going to your LBS, talk to them, if you are having any issues or concerns bring it up to them and see what they say.

It could be an issue of just raising or lowering your stem even...

But don't blame your LBS for not doing a huge fit on you... at the moment you bought the bike you didn't have enough information or feedback to make going through the routine of a "full fit" worthwhile.

It sounds to me like the kid who set it up similar to how he has his bike did the best thing for you.. Since he has knowledge and experience of that bike and well you have little to none until you actually get on the trail with it.


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