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I just bought a Madone and I need some help w/ the proper stem length. I bought a size 52 bike that comes w/ a 90cm stem. I came from a bike that was too small for me so this set up feels much better. When I am on the hoods of the brake levers, the front hub is hidden for the most part. When I am in the drops, the front hub is in front of the handlebars about 3/4 of an inch. Do I have the right stem length, or should I go longer? Keep in mind that I did the bike fit program on Wrenchscience.com and it recommended a 64cm top tube/stem combo length. Thanks in advance for your help!
 

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This is mho. First set the height of the seat. This is from the center of the bottom bracket to the top of the seat. This measurement should have been calculated for you by Wrenchscience. Then adjust the seat forward or backward depending on your style of riding, agressive, or comfy.. Once that is set, the key measurement is from the front of the saddle to the center of the handlebars. Again, this measurement should have been calculated from your torso length and your arm length. This makes sense if you think about it. Top tube + stem length leaves quite a variable when you are moving the seat up and down and back and forth. I am 6'2" and can ride a 61 cm frame, and I can ride a 57 cm frame but the two common features, the seat to handlebars is always 59cm. Just my own experience. Stamp
 

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You certainly have the right stem length according the conventional wisdom/general rule of thumb regarding obscuring the hub while on the hoods.

Of course, general rules of thumb can be meaningless because personal preferences, strength, and flexibility (or lack thereof) can give folks different preferences.

Also, the recommendation of TT/stem combo length is kind of meaningless, too. Reach is influenced by other factors including seat tube angle, stem angle, stack height, and saddle-to-bar drop. Just having a horizontal number from a computer doesn't say much.

You're clearly in the ball park (assuming you've properly set both seat HEIGHT and seat fore-aft positions) and should log a few hundred miles before making any changes. Your body will tell you if you are too stretched or too cramped.
 

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Thanks for the info guys. The bike shop I bought it from is willing to swap out the stem and bars to fit me. I already got the bars swapped to the right size. I just wanted to make a decision on the stem while the offer to swap it out is still good.
 

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when on the hoods with your elbows bent you shiuld be able to drop a plum line from the front of your shoulder and have it just touch the back of your elbow. So look in a mirror. From the side when on the hoods does your elbow appear to be in front of the shoulder. Not really then your good to go. If behind then ya need a longer stem.
 

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rounder said:
when on the hoods with your elbows bent you shiuld be able to drop a plum line from the front of your shoulder and have it just touch the back of your elbow. So look in a mirror. From the side when on the hoods does your elbow appear to be in front of the shoulder. Not really then your good to go. If behind then ya need a longer stem.

In all my years of riding, buying, and helping others I've never heard that one before. I'm not saying it isn't a good guide (still thinking about that one) but I'm just so surprised never to have heard it. My gut sense is that "plumb line from shoulder to elbow" would leave many folks too cramped, but I'll have to think about it more.
 

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jtolleson said:
In all my years of riding, buying, and helping others I've never heard that one before. I'm not saying it isn't a good guide (still thinking about that one) but I'm just so surprised never to have heard it. My gut sense is that "plumb line from shoulder to elbow" would leave many folks too cramped, but I'll have to think about it more.
watch the pros while on the hoods you'll see what I mean. Also notice how their upper arms are directly below the shoulders when in the drops. Most don't know their hips should be parallel to the ground and not tilted foward as well.
 

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I don't think the average rider could tolerate a setup like the pros ride... flexibility, core strength, and need to be super-aero just aren't typically there.
 

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Good guide for how much to bend your arms.

I'm experimenting in my chair and find that wherever my hands are, it is possible to get my upper arms in the position you describe by changing how much I bend at the hips.

My approach to this is to first get my seat so I pedal comfortably. Next I get my body so I feel balanced and centered on the bike and pedaling effeciently. Then I put my brake hoods where my hands want to go. This usually puts my upper body in a position that is difficult, but not impossible to maintain without picking up my cadence if I ride with my hands behind my back. Rotating the bars in the stem, and sliding the brake hoods in or out usually work as well as buying new stems for me.
 

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jtolleson said:
I don't think the average rider could tolerate a setup like the pros ride... flexibility, core strength, and need to be super-aero just aren't typically there.
I'm discussing reach not back angle. And pros are really not in that extreme of a position. I see 250 lb guys in more extreme position. They are in the proper position for long fast riding. If your elbows extend farther than I just stated YOU actually are in a more extreme position cause your reach is out too far. I believe the terminology that a serotta fitter uses is supporting on your bones.As a result of that your elbows will be where I described them before.
 

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rusa1586 said:
I'm experimenting in my chair and find that wherever my hands are, it is possible to get my upper arms in the position you describe by changing how much I bend at the hips.

My approach to this is to first get my seat so I pedal comfortably. Next I get my body so I feel balanced and centered on the bike and pedaling effeciently. Then I put my brake hoods where my hands want to go. This usually puts my upper body in a position that is difficult, but not impossible to maintain without picking up my cadence if I ride with my hands behind my back. Rotating the bars in the stem, and sliding the brake hoods in or out usually work as well as buying new stems for me.
exactally! you got it. There is three points to proper position. Nail em and your gold.
 

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But aren't reach and back angle, hamstring flexibility, pelvis position, etc. all related? The first part of your equation involves shoulder location (fore-aft) (ie., the top of your plumb line). And whether a rider is more upright or more aero can make a huge difference in that...
 

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You are both right in a way. The "shoulder over elbow" fit guide is sort of the gospel for a TRIATHLON set up. See for example http://www.slowtwitch.com/mainheadings/techctr/bikefit.html and http://www.triathletemag.com/story.cfm?story_id=12224&pageID=1732 as just a couple of articles about tri set up that way.

For a triathlete, you often have your saddle farther forward, saving hamstrings for the run and getting more aero. But for road riding, this is really not a rule of thumb for fit in non-racing settings. I think that MOST recreational roadies would find that attempting to follow the "shoulder over elbow" plumbline rule will have them uncomfortable.

(or they will wind up post pics of themselves on a cramped ride and be maligned forever, a la Aarontoy!)

EDIT: Ooops, I meant to attach this to the exchange about whether your shoulder should be over your elbow...
 

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jtolleson said:
But aren't reach and back angle, hamstring flexibility, pelvis position, etc. all related? The first part of your equation involves shoulder location (fore-aft) (ie., the top of your plumb line). And whether a rider is more upright or more aero can make a huge difference in that...

your reach is your reach regardless of flexibility. Your drop from saddle to bars will take into account flexibility. Your arms and torso are a certain length and won't change. I see what your saying because taken to the extreme of a totally upright position my plumb line reference wlill not work.On a road bike you don't ride any more upright than 45 degrees in the hoods. 45 degrees is very upright in the hoods by the way. Usually someone is set up to ride at a 35-25 degree angle on the hoods with 35 being more prevalent. Anyway, at those angles the plum line reference works. When a rider goes more aero their handlebars go down and not foward. To go foward puts excess pressure on the shoulders and traps to support the upper structure. Arms form a 90 degree outer angle from the support point of your hands. Your elbow will touch a plum line dropped from the front of your shoulder. This also solves what to do with a person with long arms in relation to torso. They go down and not out like superman.
 

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baylor said:
You are both right in a way. The "shoulder over elbow" fit guide is sort of the gospel for a TRIATHLON set up.

Who's both?

In a static set up position to determine if the stem length is right you can look to drop a plum bob from the front most point of the shoulder and the rearward most portion of the elbow will touch the plumline while ON THE HOODS. That is what we are discussing here.
The rider position above has correct reach but he lacks flexibility so he is bending too far with his upper back and having a difficult time raising his head up. Hips look good and so does seat height.
 

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Flite500 said:
Great pics for us newbies...I really appricate seeing this stuff!!

Thanks!!
No problem glad to help. Mirror the 2nd pix and not the 1st as the 1st pix is not a good example of proper fit because he is actually pulling himself into that position due to a lack of good basic flexibility. The reach on his pix is fine but the handlebars are too low for him even though he has little drop.
 

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If by the "first pics" you mean the photo of Aarontoy, I think that was posted as a joke. That photo has floated around the board as an example of a too-cramped rider (and other inside joke for a long time). I don't think it was posted to show proper fit. The reach for Mr. Aarontoy is not remotely fine.
 
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