can someone explain to me...

[poy]

what would be effects of shortening the stem on my bike? besides the ride are there also safety issues to be considered? any tips? thanks!!!

[BFloFoxRider.]

you would feel more in control with the front wheel... the feeling would be different since your riding position will be more upright, but steering should be tooo much different.

[RacinJason]

When shortening the stem you will get a little more stability.
I use a 50 mm stem on my DH bikes.
On XC bikes I like 70 mm stems.

[Rockinthecasbah]

you will get your weight shifted farther rearward and you should feel more in the bike then stretched over it, you will loose some sit down room which may bother you climbing but you will gain control of the bike

[poy]

any bad sides to it... like do i get a bigger change of going over the bars? you know things like that...

[BFloFoxRider.]

Originally Posted by poy

any bad sides to it... like do i get a bigger change of going over the bars? you know things like that...

Nope, the wheelbase is the same.. you may get the sensation of feeling too far over the bars at first but i wouldnt say it'd make you more likely to endo

[poy]

does it improve more for the up hills or the dh? i noticed that dh bikes have 50mm and i was trying to think of why it would be better. i noticed xc bikes uses 90-100mm but if xc goes 50mm will it do anything?

[BFloFoxRider.]

Originally Posted by poy

does it improve more for the up hills or the dh? i noticed that dh bikes have 50mm and i was trying to think of why it would be better. i noticed xc bikes uses 90-100mm but if xc goes 50mm will it do anything?

The shorter stem usually makes the bike feel shorter, and easier to flick side to side, while XC and the longer stem the racers like to be spread out more, and i found it makes it easier and more stable on the climbs

[bighit8]

I went from a 110 to a 80mm on my mongoose because I felt to stretched out on the bike.The front is much more stable since I went to a shorter stem.It is dependent on the rider and what feels right.I imagine if you go to short the cockpit will feel confined.

[poy]

ok... now what if... an xc/trailbike switches to 50mm stems and put longer handlebars. does it zero out then?

[BFloFoxRider.]

Originally Posted by poy

ok... now what if... an xc/trailbike switches to 50mm stems and put longer handlebars. does it zero out then?

what was the original size stem?
and longer handlebars?
maybe wider, but that would just be personal, and i think bikes with wider handlebars are easier to control, but for a trailbike i wouldnt reccomend them too wide.
IF you bars have a backsweep, if you switched to a shorter stem but lost some backsweep it may "zero" out, but it wont feel exactly the same

[poy]

hahaha! its incredible how much a few mm changes ride/comfort/safety/looks... with all these "small"adjustments my mtb might end up like a beach cruiser!!!

[jeffj]

Originally Posted by poy

any bad sides to it... like do i get a bigger change of going over the bars? you know things like that...

You don't automatically adjust because you use a shorter stem. Your feet are still connected to your pedals in the same place. You have to make a conscious effort to adjust, especially when clamping on the binders (braking). I had some close calls the first few rides with a shorter stem during hard braking at higher speeds in spots that were not steep descents.

It will be easier to sit more upright and have less pressure on your bars (hands) which could affect climbing steep hills. You may have to apply more pressure on the bars. I would even say it generally will have a negative affect on climbing if your bike fit properly in the first place, but you may find the tradeoff well worth it.

Like all bike fit issues, the key is finding the best balance for your style of riding on your bike.

[Marshall Willanholly]

Here are some good discussions on stem length from LeeLikesBikes. He's the author of Mastering Mountain Bike Skills, and was just out here teaching clinics. I had the opportunity to take a 3 hour clinic with him on Monday and it was incredible. The guy really knows what he is talking about.

http://www.leelikesbikes.com/stem-le...rail-bike.html

http://www.leelikesbikes.com/stems-a...-and-high.html

http://www.leelikesbikes.com/stems-h...too-short.html

http://www.leelikesbikes.com/again-t...ght-thing.html

http://www.leelikesbikes.com/cockpit...aapablity.html

http://www.leelikesbikes.com/corneri...hort-stem.html

[pastamon]

Poy,

to me at least, a better question is why you would want to know. If you want to know because you plan to make a stem change, the best way is to simply make the change and see what you find out for yourself.

The answer to your question is something that cannot be described, because the shorter stem changes things subjectively. I have read people saying it makes the steering "faster" and others saying it makes the steering "slower." Some say it becomes "more responsive" and some say it becomes "more muted."

Personally I find that a shorter stem gives me better feel for where the front wheel is, and the longer the stem becomes the more I feel like I'm out in front of the front wheel, rather than behind it and steering it.

At the same time you need to have your body positioned properly on the bike and if you make the stem too short for your fit on the bike, a lot of other things get screwed up. Shorter stems make you sit more upright. The more upright you go, the less you can use the big muscles (glutes, hamstrings, lower back) when you are putting down the pedal power.

The best way to know is to simply try a shorter stem. What size stem does your bike have now? Why do you want to change it?

If your bike has a really long XC-style stem of 110-120 mm then you'd probably find moving down 20mm or so would be a significant change.

If your bike has a 70mm stem, then you're not going to find a lot of difference in moving to a 60mm or 50mm stem.

Originally Posted by Marshall Willanholly

Here are some good discussions on stem length from LeeLikesBikes. He's the author of Mastering Mountain Bike Skills, and was just out here teaching clinics. I had the opportunity to take a 3 hour clinic with him on Monday and it was incredible. The guy really knows what he is talking about.

Lee does know his stuff and he is a great instructor. At the same time, he tends to make suggestions for primarily gravity-assisted riding.

Lee tends to suggest 50-70mm stems for everyone for everything. Now here's the important thing -- he's still learning, he'll admit this. Recently he had to change his views on elbow positioning, and he'd been adamant about the prior position that he advocated, despite the fact that now he finds it was wrong or less efficient.

A 50mm stem is STUPID for someone who lives for XC riding and racing, and lives to climb. STUPID. Not everyone is Lee, not everyone races 4x and DH. Too short a stem and you can't keep the front wheel tracking on a climb, unless you spend a lot of (wasted) energy fighting the wheel's flopping side-to-side. There are techniques to counter this but they sap your energy and if you like to do long rides, the wasted energy adds up and becomes frustrating -- to me at least.

I went from 110mm stems on my XC bike in 1999, to 50mm stems on big FR bikes in 2003, and I'm back at 80-90mm as best for all-around. What works best for any person depends on the person's trails, riding style, preferred bike position, and what the rider likes best about riding.

[Marshall Willanholly]

Originally Posted by pastamon

A 50mm stem is STUPID for someone who lives for XC riding and racing, and lives to climb. STUPID. Not everyone is Lee, not everyone races 4x and DH. Too short a stem and you can't keep the front wheel tracking on a climb, unless you spend a lot of (wasted) energy fighting the wheel's flopping side-to-side. There are techniques to counter this but they sap your energy and if you like to do long rides, the wasted energy adds up and becomes frustrating -- to me at least.

I went back and read through the linked articles again. I must have missed where Lee suggested a 50mm stem for "someone who lives for XC riding and racing." The questions and Lee's answers seemed mostly to refer to trailbikes, such as the one from the first link I posted:

Hey Lee,
I love the book — every time I ride, I pick out something to work on and try to nail it. But I’m curious…
I want to try a shorter/higher stem to improve my descending and (small) drops.

From another link discussing cockpit length:

Originally Posted by LeeLikesBikes

- Longer cockpits (within reason) tend to aid seated pedaling because they 1) open up your upper body and 2) encourage you to rotate your torso and hips forward. These things tend to improve efficiency. You can learn to climb with a short cockpit, but most riders climb more powerfully with a longer one.

- Given the same wheelbase and/or cockpit length, shorter stems handle better (are more braaapable) than longer stems. 1) As you turn the bars, shorter stems have less side-to-side sway. 2) Shorter stems place the bars farther behind the front hub, which makes bikes feel better on fun terrain. It’s no accident that the more terrain-oriented a bike is, the farther its bars are behind the front hub.

I'm just not seeing a blanket endorsement of 50mm stems. Maybe I missed it?

I posted the links so the OP could get an idea of how a shorter stem might affect the handling of his bike. As the original post said:

Originally Posted by poy

what would be effects of shortening the stem on my bike?

I think Lee presents good information on that topic. Sorry it got you so worked up this morning.

[strobelite]

think putting a smaller dia. steering wheel in your sports car.

[Pho'dUp]

Fitting is a complex and totally depends on the individual. I think everyone's comments are great. Great general info, but you can't talk specifics without knowing a ton of info. about Poy. Like what bike? What size is it? Riding style? Poy's body type. etc. it goes on forever. Then I think it's just trial and error. You can get a professional fit too which may help. But I, like most others, have a whole box of stems/handlebars/seatposts at home that are different lengths and rises.

Another general idea would be just to go to more rise with your handlebars and keep the same stem. That effectively shortens the cockpit too.

[roguemoog]

I am about to go through the same thing. My first bike, which I'm still on after 3 summers of riding, was a small Hardrock. The guy at the shop put a longer stem on it for me because he watched me ride around and thought it would help my posture. That bike has felt great and I've gotten super comfortable with it.

I just picked up a medium Kona. It's 1" larger (my small Specialized I believe was a 15") and has a much higher standover, but the biggest difference I've noticed is with a "normal" stock stem, I'm MUCH farther back.

I do feel like I have more control turning, it really does feel pretty good. But not h