Frame Sizing Dilemma
 

Okay, here's the background. I haven't been a roadie in 20 years... alot has changed, not the least, is my priority to get a properly sized bike this time around.

I'm 5'11" with a 31" true inseam. It would appear that I'm disproportionally long torsoed (I'm sure that's probably debateable). I assumed with my inseam that a 56cm would have been the logical choice, however the saleperson doing the floor fit recommended a 58cm because she felt I was a bit hunched over the 56cm. Now this could be because I'm not able to spread out enough, or I just have sucky road posture, not really sure at this point. Time on any road bike will probably answer that one.

This is on a 2006 Trek 1500 which I assume is a somewhat standard geometry.

One opinion I get is that the TT length is more important than the ST and the seat can be adjusted wherever, however I'm actually running my seat post only about 2" out.

The other opinion is that it's better to get a smaller frame and opt for a longer stem, if necessary.

Lacking carbon stays, I'm a little hesitant to neuter the carbon seat post's effectiveness by running it at such a short length, not to mention I'm a little hesitant to ride a frame that's going to be a nut buster.

I really like the bike and really don't want to switch over to something else if I can avoid it. :D

The simple answer is: take your chances. The better answer is: spend a little cash on getting a fitting. It seems that you might be a bit long in the torso and yes the top tube length is important. In addition, stem length changes affect the handling of the bike. You should be able to be professionally fit (eveyone claims to do this, but ask around and find someone who REALLY does this) for about 100-200 and most shops will knock this price off of a bike if you buy it from them after the fitting. Since you are in the pacific NW, take the trip in to seattle and go to speedy reedy (they are just great). Gregg's has one or two people who know how to fit you, but I have found them not as willing to work with the customers due to high volume. Most shops claim to be able to get you fit correctly, but ask cyclist in the area. They will be able to guide you well.

Also, if you like measurements, check out http://www.competitivecyclist.com/za...LCULATOR_INTRO

this is nice because they give you three different fits depending on your likely riding style. Best of luck.

ALSO TRY: http://www.wrenchscience.com/WS1/Secure/Fitting/Height.asp

Ditto! it may all seem foreign initially, but having some idea of your fit before you buy helps to make a more informed decision. If you know your overall reach combined with say 100mm stem, it allows you to weed out frames that may be ill fitting. Effective Length (not actual) of Top-Tube should be your primary concern if you're looking at compact geometry. I ride a 55cm Lemond with an effective T-T Length of 56.5cm, after some shoulder pain and fit calculators, I've come to find that this frame is "appox" 2cm too long. I'm currently using a 90mm stem and the fit is still a bit long. See if an extended test ride is possible, a few miles at the very least.

I think TT is more important and more difficult to adjust if you get the wrong length. The seat tube height can vary a lot without affecting handling a great deal, also you don't have to replace the seat tube. But if you get the wrong TT length, you'll be forced to:

1) Change the stem length. Can be expensive because the stems have to be replaced instead of shortened or lengthened. Also, shortening makes the handling jittery while lengthing can make response feel slower.

Or

2) Change the seat's forward / backward setback which will change your knee placement above the cranks which can hurt or hinder performance, extension, muscles used ...

I rode like 10 bikes total averaging 5-10 miles each before selecting one. In the end I took a 50cm Cannondale with a 51.5cm TT as the most comfortable. This is also, factory fit, seat in the center position and 100mm stem, the bike shop is giving me a fitting as well, but I wanted the best "starting" point.

Hey pcwace,
I saw your bike picture and judging by the setback on your seat post and the long stem the 58cm was probably the right choice. How does it feel when you ride? BTW, I think that carbon seatposts are over-rated for taking the road buzz off your butt. A decent saddle would help alot there.

Well... I remeasured everything and plugged those figures in :

Competive Fit ST = 53.5-54.0
Eddy Fit ST = 54.7-55.2
French Fit ST = 56.4-56.9

Competive Fit TT = 55.2-55.6
Eddy Fit TT = 55.2-55.6
French Fit TT = 56.4-56.8

The 56cm Trek frame's ST=56 (duh), TT=55.8
The 58cm Trek frame's ST=58(again, duh), TT=56.9

To answer Mariner Fan's question, I feel a bit stretched out on that 58.. that's what started my doubts. I FEEL better on the 56

.....Get a fitting at your LBS....

I think that goes without saying, but to going into an LBS blind, "trusting" everything the sales people say, "trusting" the fit will be done properly is a recipe for frustration. There's absolutely nothing wrong with being an informed shopper.

I'd say that's progress! calculators have closer to the 56cm than the 58cm and you think the 56cm felt better so I would start riding as many 56's as possible. I would prolly still ride some 58cm's just to be sure, but at least you have "some idea" of where you should be which more than I knew when I bought my first roadie :( .

Post your bike picture on this thread to show what you have. You are a bit stretched out on the 58 but it looks like your stem is a 120. Most bike shops will change that out for free when you buy a bike from them. If not PM me I have a ton of them....

I have a feeling your going to be happier with a 58 with your long torso as long as you can straddle the Top tube o.k.

I have the opposite problem than you. I have a Lemond and they are known for long top tubes. My body type is long legs and short torso so in retrospect I probably picked the wrong bike. You can make this work with changes to the stem. You stated that you have a long torso and if you choose to go to a smaller frame you may feel cramped. The new trend is to put a rider on a small frame and adjust for the body type. I’m still trying to dial my fit in with progressively shorter stems to get to the point where I don’t feel stretched out. The bike came with a 120 stem and I just ordered a 100. Hopefully that will work for me.

Mariner Fan--I recently got a Lemond as well. I moved the seat forward a little because the stock post has a lot of offset. Before going to extreme with the stem you may try shifting the seat a little (especially because it is free).

Sorry to highjack this thread. I actually had to move the saddle back to try to get close to a KOPS fit. Like I said, I’m still trying to dial it in (hope the weather breaks soon). Some bikes have inherent properties that work for certain body types.
pcwace would probably fit on a Lemond perfectly!

The calculator is suggesting a average of 110mm on the stem for me. I have no idea what the stem length, since Trek's site says it's a 38.2mm (I'm assuming they are referring to the bar length it's mated to?).

Here is the pic of the 58cm after my floor fit.

http://www.nitrorc.com/matt/images/trek1500-1.jpg

(try to ignore the upswing in the bar... I had just flipped the stem and hadn't had a chance to properly align the handle bar)

Same boat with my 55 Lemond, down a 90mm stem right now...a new frameset is next.

Sorry for the thread jack, but I am in the same boat as the OP. My LBS is not very helpful at all,it seems like they don't want my sale. Anyways I did the online calculator and came up with

The Competitive Fit (cm)
-------------------------------------------
Seat tube range c-c: 52.6 - 53.1
Seat tube range c-t: 54.3 - 54.8
Top tube length: 57.0 - 57.4
Stem Length: 11.6 - 12.2
BB-Saddle Position: 76.0 - 78.0
Saddle-Handlebar: 54.8 - 55.4
Saddle Setback: 3.2 - 3.6
Seatpost Type: NON-SETBACK

Does this mean that I should be in the 54 range (Seat tube range c-t:54.3 - 54.8) or the 57 range (Top tube length:57.0 - 57.4). I am confused as which #'s I should go by.

The Trek site says it's a 31.8 mm stem with a 17 degree rise. Your stem is flipped down and the 31.8 refers to the size of the handlebar (or oversize). If the stem is a bontrager you can look at the part that connects to the steerer tube and the length will be stamped. If not you can measure the stem center to center.

To be honest I did this fit test and it had me on a 64cm bike! The best way to fit a bike is to ride it for awhile. You have to patient and realistically evaluate how you want to ride. Use this guide as a ballpark figure then go ride bikes.

Okay.. I see it now. It's stamped with 100mm, so I'm 1cm shorter than the calculator suggests.

i'd go with the 56. if thats where your seat ends up the frame looks too small to me.

I don't know if this bike fits you . . . but, it certainly looks like it's ready to go: it looks a lot like the setup that I prefer, e.g., the tops of the bars are about level with the saddle so you still have the use of the drops if you need to take a more aggressive positon, such as against a headwind: otherwise, it looks comfortable. Plus, I like triples. :)

Here's your problem - don't use your inseam. Use the distance from your crotch to the floor, i.e., the bottom of your feet.

If your pants reach to the floor, I would suggest you have a discussion with your tailor.

I assume you are not going to be pedaling with your ankles, which is why inseams can be deceiving. For a true distance, you need to measure all the way down.

Treks are mostly mid-stream fitting bikes, not too long and not too short. Prolly will fit 99% of the riders that walk thru the door.
If you're deciding on 'size', the smaller frame size will have a shorter headtube and for traditional horizontal TTs, a lower 'standover'.
Consequences? if your nutz are draggin the TT, go smaller. A shorter headtube did have consequences (way back) on handlebar height (with oldstyle quill stems), but now with stems of varying angles, that's less of an issue.

Maybe consider a model with 'compact' construction (sloping TT)? They give plenty room for the 'equipment' and still has much of the setup of a traditional frame. Unless you don;t like the looks of 'compact'.

If its a choice of a frame that seems 'just a hair small' V one that is "just a hair tall' - go smaller. Easily adjusted with seatpost and stem; and a longer stem has the added advantage of gettting more weight over the front wheel and thats all good for handling.
Caveat - some frames have very upright seattube angles, beware and stay clear - they will be a bear to position well, unless you spend 90% of your time riding in a Time Trial position and with TT bars.
But I'd be surprised if Trek did that on any mainstream bike not noted specifically as "Tri" or "Time Trial" machine.
The real key is to 'position' the seat properly - and that hasn't changed over the years. Everything else gets 'adjusted' after that.
Even if you 'decide' on a bike before a fit session, its still worth doing a fit session on a real 'fit' machine to get some 'Standard Benchmark' around which changes/variations can be gauged. The Serotta system seems to be one of the better ones; there are others...

It looks like you may need to go smaller. You said that you feel streched out with the 58 and your stem length isn't long. Will the bike shop allow you to trade for a 56?

FWIW Lance is 5'10" and rides a 58cm Trek. I would say 58 for you if you can handle the reach without having to use too short of a stem, I like to stay above 100mm stem length. If you go with a 56 you may have a problem with drop from seat height to handlebar. Too bad Trek doesn't build their bikes in 1 cm increments.

Al