# Change stem length to fit a MTB that's one size too large?



## quickmammoth (Jun 18, 2014)

I recently purchased a 2013 Cannondale Trail SL3 in their Large size. After my first ride, I'm suspecting that it may be one size too big. 

Even with the seat positioned as far forward as allowable, I can easily achieve full extension of my arms when sitting on the rear 1/3 of the seat with body leaning forward. In order to get some bend in my arms, I have to lean more forward than I would unconsciously position myself. More often than not, I find myself, instead, shuffling up to the front 1/3 of the seat. I went for my first ride yesterday and this morning, there's some soreness in my neck and lower back. 

To add to my suspicion, everywhere I've looked online (plus talking with bike shops) tells me that I should be riding a Medium (I am 5' 8''). 

I test rode a Medium today (not the exact same model, but the geo numbers are similar to my model's Medium size) and, to get full arm extension with the same forward lean, I had to sit just past the rear end of the saddle. Sitting at the rear 1/3 of the saddle with the same forward lean gave me slight bend in the arms (that's the desired, right?).

I think the reach is a tad too much. For me, there's no issue with the standover.

I don't want to be hurting my body unnecessarily because of a non-ideal fit on my bike.

Since standover isn't an issue, would simply reducing the stem length do the trick of achieving the same kind of fit I'd expect on a Medium in terms of reach? Or are there other frame geo factors between the Medium and Large that play a role in rider fit as well?

What it ultimately comes down to is whether I need a new stem or a new bike altogether.


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## joel787 (Nov 21, 2011)

can u return it? how long is ur stem now? check a zero set back seat post if u need one, around 20mm u would be fine, anything above that u start changing the characteristics of the bike.. i think the handling gets affected when the bike is too big, u have to exaggerate some body movements to get certain responsiveness out of the bike


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## eb1888 (Jan 27, 2012)

5'8" you should not be on a large.


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## TenSpeed (Feb 14, 2012)

OP - can you post a side shot of you sitting on the bike in the current state? Your height is a bit off to be on a large, but that doesn't rule it out that it might fit you. Depends on your body, arm length, torso length, leg length, etc. What size stem is on there currently?


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## BushwackerinPA (Aug 10, 2006)

its better to be a long top tube with short stem then a short top tube with longer stem.


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## AndrwSwitch (Nov 8, 2007)

eb1888 said:


> 5'8" you should not be on a large.


At 5'8", I feel borderline.

Between a medium and a small.

Can you return it?

While you can make a bike fit your body by messing with the stem length, it'll really mess up the handling.

I held onto a too-big road bike for years because I got a good deal on it and then didn't have that kind of extra money for a while. Nice bike, but I could never set it up so it was easy to climb in a straight line and didn't hurt me. Handling is even more important off-road. You really need to be able to move both forward and back over the bike without running out of range of motion.


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## Ronnieron12 (Mar 4, 2014)

If this bike is new from a shop def. return it. You never know how a bike fits till you get on it. I have two large bikes and two mediums all fit great. Im 6ft and if I went by every manufacturer's recommendations I would only ride a large. It you can't return you can adjust the stem length, seat position, and bar width. I just feel at 5'8 its going to be a stretch.


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## DiRt DeViL (Dec 24, 2003)

I'm 5'8" and ride a large (19") with a 90mm stem and 0 setback post.

Can you share your bike, stem and post dimensions?


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## quickmammoth (Jun 18, 2014)

Thanks guys for the replies.

Here's a pic of me on the bike:









The stem is 90 mm center-to-center. The saddle is at zero set-back. The handlebar is 680 mm.

In this pic, I have a slight bend in the arms. But I can easily lock out just by leaning back a bit. Since I'm relatively new to MTB, I'm not entirely sure what to expect in terms of the 'proper' riding position... maybe that's normal?

Complete bike dimensions can be found here. It's the Large.

Seat tube length: 18.7 / 47.5
Top tube (horizontal): 24.2 / 61.4
Top tube (actual): 24.5 / 62.2

The shop is transferring in a 60 mm stem to swap. They say that it's all that is needed to correct the fit since standover isn't an issue.

The shop guys are pretty cool and knowledgeable, but I'd like to get a second opinion from people who didn't sell me the bike.

I'm really hoping I can keep it since I got a good deal on it. I won't be able to find anything comparable in quality at the price with 2014 models.

Ultimately, though, I don't want to be hurting my body because of a bad fit on the bike. That, and/or a compromised handling because of the resulting adjustments are reasons enough for me to overlook the 'good deal' and return the bike.


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## someoldfart (Mar 14, 2013)

That fit looks great to me. A shorter stem will make bike handling better I think.


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## TenSpeed (Feb 14, 2012)

That looks like about a perfect fit if I have ever seen one. Was expecting something completely different. Let us know how the new stem is.


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## perttime (Aug 26, 2005)

It doesn't look too bad. My preference would be a little smaller, to get a more nimble bike.
Leaning forward a little is quite normal. It puts the rider's center of gravity lower which makes me feel more in control.

Can you move your weight back on the bike? When rolling on the bike, cranks level, can you get your backside behind the seat for riding down the steep spots? Or do you run out of arm length there? 30mm in stem length can make a world of difference there.


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## AndrwSwitch (Nov 8, 2007)

I hate when people post pictures of themselves sitting on bikes, leaning against a wall. I could pick apart your position, but I don't know if it's your position - what matters is how you fit on it and how it handles when you're riding.

I like a 585-590 mm top tube and 90 mm stem. So sticking a 60 mm stem on your bike gives you and me about the same reach, but a different weight distribution.

So the real question is how does it ride? I don't like stems that short, but some people on the site swear by them. I think a lot of it has to do with how you feel about flat to climbing singletrack. I love getting to the tops of things, so probably most of my time spent mountain biking is spent climbing. Of course I get a kick out of descending. For me, a medium has nicely balanced handling. I could see having a different attitude if I did all my climbing on logging roads.

Here are some things to try. When you're coasting, put your pedals at 9 o'clock and 3 o'clock and lift your butt off the saddle. Try not to have any weight on your hands - really balance over your feet. Do you have to correct toward the front or back of the bike?

When you're riding, do you have much weight on your hands?

If you take your hands off the bars, does your bike become super twitchy? Do this without changing your position.

How long do you need to keep this bike to feel like you got your money's worth?


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