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Discussion Starter · #1 ·
I currently ride a 08' Fuji Roubaix 56cm and it fits fine in the legs but I am way too stretched out to the point now that my back is hurting pretty bad. I bought it just to commute and stay in shape for mtb season. But I caught the roadie bug and am riding it a ton. So, I need to find a new frame but I am not sure what size to look at. I have done competitive cyclist and the wrench science fit calculators and they come up with this size frame for my body.

Top Tube: 50.7 - 51.1
Seat Tube C to C: 52.4 - 52.9
Seat Tube C to T: 54.1 - 54.6
Stem Length: 10.2-10.8

I am 5'9" with just under a 32" inseam. So my question is this. Is the top tube or the seat tube measurement more important. Because there really inst a frame out there with a 51cm top tube and a 54cm seat tube. Is there a general rule when it comes to this sort of thing? Thanks.
 

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on-site calculators aren't accurate. go to a bike shop and ride demos. the top tube dimension is important. What makes you think you need a 51 top tube? all you need is a lightly smaller bike with a shorter top tube. try riding a 53cm bike with a longer seat post. always use a least a 10cm long stem. How much dimension between top of saddle and top of handle bars do you currently ride with? Cannondale road bikes size 48 have a 51.5 top tube, but you'll need a 400mm long seat post.
 

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that tt rec is pretty short, in general and in relation to the st... I doubt you'll find a stock bike with geo like that, unless you look at wsd/womens models

why "always use a least a 10cm long stem"??? can't always just go to a smaller bike w/ longer sp without having problems w/ too much saddle to bar drop, e.g., bars will be too low
 

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rydog9991 said:
Top Tube: 50.7 - 51.1
Seat Tube C to C: 52.4 - 52.9
Seat Tube C to T: 54.1 - 54.6
Stem Length: 10.2-10.8

I am 5'9" with just under a 32" inseam. ...
are you sure your inseam is 32"?

this site shows you are around avg.

http://www.prodigalchild.net/Bicycle6.htm#FrameChart

a traditional geometry bike is better than compact geometry if you are truly that short on the torso.
 

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Discussion Starter · #6 ·
cmg said:
on-site calculators aren't accurate. go to a bike shop and ride demos. the top tube dimension is important. What makes you think you need a 51 top tube? all you need is a lightly smaller bike with a shorter top tube. try riding a 53cm bike with a longer seat post. always use a least a 10cm long stem. How much dimension between top of saddle and top of handle bars do you currently ride with? Cannondale road bikes size 48 have a 51.5 top tube, but you'll need a 400mm long seat post.

I figured they were not too accurate but, I thought they would at least give me somewhat of an idea of what to look for. My current set up I ride with the saddle a couple inches higher than the handle bars. My girlfriend did the measuring for me so who knows how correct it is but it should be close.
 

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FatTireFred said:
that tt rec is pretty short, in general and in relation to the st... I doubt you'll find a stock bike with geo like that, unless you look at wsd/womens models

why "always use a least a 10cm long stem"??? can't always just go to a smaller bike w/ longer sp without having problems w/ too much saddle to bar drop, e.g., bars will be too low

my experience with short top tube bikes gets me to the 10cm stem. good starting point you can go down to a 9cm without effecting steering too much or go up. when get down to an 8cm they do get squirrely when you hit the brakes. most short top tube bikes have steep seat tube angles so the center of weight is forward. except some cervelos, konas, titus, BH, lemond frames......
 

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Discussion Starter · #8 ·
Here is a pic of my current set up. Stem is 90mm. I hate the feel of the short stem but I had to do it to make long rides bearable.

 

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Agree with the above posters - your inseam is not out of line for your height.

That being said a 56 frame may be too big for you - go test ride some 54's. Sounds like bike frame size may be your issue.
 

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bq_or_bust said:
a traditional geometry bike is better than compact geometry if you are truly that short on the torso.
Hold on, what does it matter if a frame has a sloping top tube or a horizontal top tube in regards to fit??

The sloping top tube bike can't be measured the same way as a horizontal top tube bike but so what? The "compact" geometry changes where the top tube attaches to the seat tube. So you put a longer seat tube in and all is the same again.

If you where to buy a compact framed bike that had the seat, crank, and handlebars in the same place as the traditional bike, the only difference compared to the traditional bike is the longer seat post of the compact bike.

The only time it matters is if the manufacture makes less frame sizes and one of the frame sizes you fit best is one that is not made.

S-
 

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Other than effective top tube (ETT) length, you have to look at head and seat tube angles (HTA & STA) as, the more steep each or both of them are, the greater your effective reach with a given ETT.

For example, visualize this:
Bike #1 has a ETT of 58, a STA of 74 deg and a HTA of 74 deg.
Bike #2 has a ETT of 58, a STA of 72 deg and a HTA of 72 deg.

Bike #1's vertical STA "pushes" the top tube forward and the HTA "rotates" the bars farther forward and downward.

Many crit racing bikes has geometry like this. The HTA and STA are "steep".

Bike #2's STA "pulls back" the top tube and its HTA "rotates" the bars higher and farther back. The HTA and STA are "lax".

Many entry level road bikes, "comfort" road bikes, touring bikes etc. have this geometry.

The seat tube length is relevant to standover height but not much else. Don't obsess over that.

Last to consider is the head tube length, obviously the longer it is, the easier it is to get the bars higher while still using a 8 deg stem. Relevant for long legs/short torso riders.

So I'm telling you what you don't want to be told, your bike probably has a HTA and STA that are too steep for your physique and you should get a different frame with more "lax" geometry.

Bikes like the Specialized Roubaix and the Giant Defy have such geometry.
 

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If you feel like the reach is too long, change your bars. You can shorten up things quite a bit without much of a penalty with short reach bars like the Easton EC90 SLX3. It would move you back quite a bit. I use them and love them.
And if you shop for a smaller frame then beware that you may end up with the bars too low and then you have new problem to deal with. This is a long process of testing riding bikes while taking the time to set them up properly and seeing if you fit properly.
 

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Try a bike with WSD geometry. There are plenty of man-friendly colors out there, but they're specifically made for proportionally long legs & short torso.

It's pretty dumb that they call it "women's specific" when there are a lot of women (myself included) who aren't built like that, and plenty of men that can benefit from it.
 

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If you really don't want to use a short stem, look for a frame with the seat tube longer than the top tubes. (Certain builders generally do this, such as Colnago)... Also look for a frame with a longer head tube, or the type of headset that extends some from the head tube. That way when you get a small frame in order to have the right TT length, you don't have to use a crazy amount of spacers.
 

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winders said:
Hold on, what does it matter if a frame has a sloping top tube or a horizontal top tube in regards to fit??


S-
Because if he is an individual with longer legs than the average person with his torso size, buying a compact frame bike with the appropriate top tube length will yeild too much seatpost being exposed. Compact frames already have a lot of seatpost showing. Other than that, you are correct, it doesn't matter.
 

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+1 on bar change

gh1 said:
If you feel like the reach is too long, change your bars. You can shorten up things quite a bit without much of a penalty with short reach bars like the Easton EC90 SLX3. It would move you back quite a bit. I use them and love them.QUOTE]

You might also try something a little less pricey, like the Salsa Poco or Ritchey BioMax II Pro bars. Both have a combination of short reach and short drop that will shorten your reach considerably, both to the tops and the drops.

The stock bars look huge, out of proportion, on that Fuji.
 

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NOT long legs...

I would put no value at all in the information from that fit calculator. It's totally wrong.

If your cycling inseam is 32 inches or 81cm, you don't have long legs. Your saddle height should be in the 70-72cm range. I'm 6cm shorter and have 2cm longer legs - that is long legs and short torso.

The biggest problem with your current bike is that you have long reach bars and Shimano shifters that also have a long reach. It's also at least one size too large, but going down to a 54cm would only reduce the reach by 10mm or one stem size. A 52cm would decrease the reach by another 10mm, but the head tube length would probably require a higher rise stem.

Just switching to some short reach bars would help a lot.
 

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As for bars, Specialized makes bars with a 78mm reach/13?mm drop; the drop is less than 140mm which makes it shallower than deeper.

I believe they are the "Comp" bars, I do know they cost $45-50. For a 31.8 bar, that's comparatively cheap.

The Biomax's have something like a 75mm reach/130mm drop, though. And that's really short. As well, they are swept back, like a mountain bike handlebar, which further shortens the reach. In a 31.8 clamp they retail for like $80 but they might be worth the extra money. My Divano came with these, they're pretty nice.
 
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