Road bike fitting(sizing) confusion
 

First, greetings to all :D

I am 186.5cm tall and inseam = 90,5 cm . What is optimal road bike frame for me ?

I used all calculators available on the internet, and they cant agree for the right frame size.

some of them suggest down from 57cm , and maximum I got is 62 cm.

There are many frame manufacturers today and some of them produce classic frame some produce sloping frames.

If we watch effective top tube it can wary from 55 to 59 for 59cm frame size.

Ill write down some tables, so if someone can give opinions related:

one frame type :
57cm seat tube , 57.4cm effective top tube 73°
59cm seat tube 58.7cm effective top tube 73°

other frame type:

57cm top tube 55,5 cm eff top tube
59cm top tube 57cm effective top tube

The thing you're going to need to worry about most is the reach. Top tube length plus stem length (horizontal). Find one that fits you that way and the seatpost tube measurement will follow.

Go to a good bike and have them measure you from head to toe so they can determine what frame would be good for you.

There is a bike shop in my city that will do a Retul pre-fit to determine what frame fits best and then the post fitting to dial the bike in for $250 and $150 of it is discounted off the bike if you buy the bike from them of course. See if you can find any shops in your area that do this kind of fit.

You would probably be happy on a traditional frame of about 59 to 60cm seat tube c/c. In a sloped top tube bike, probably size large. It is an inexact science.

The seat tube length has no effect on the fit.

The head tube length, or better yet, the frame stack is what really defines the vertical size of a frame. Most brands now have comfort fit models that have 15-30mm more head tube length, but the frame "size" is still listed the same.

Frame reach is important, but the vertical size changes far more than the reach, as you jump from one size to another, within a given brand and model.

A 90.5cm cycling inseam should require about an 80cm saddle height. You would want an absolute minimum 190-200mm head tube length for a road bike with a common 7cm BB drop. With a 190mm head tube, a 15mm headset top section, one 10mm spacer and an 84 degree stem, you'd have a saddle to bar drop of about 9cm, which is more than most beginners can tolerate.

To compare the reach of different frames, you can compare the effective or virtual TT lengths (which really means horizontal TT length), but only if the seat tube angles are the same. If one model has a steeper STA, then add 1cm per degree to the TT length of that frame before comparing the length.

http://www.cervelo.com/en_us/bikes/2010/R3/geometry/

I would say that it should be opposite for sloped tubes ? because seat tube top is lower compared to traditional frame , or below the head tube, traditional frame has head tube in the same height as seat tube ?!

For example see this :
http://00211.12trade.de/Rennrad-Rahm...woeiu%2Bv.html

Seller suggest me 61cm, but I think maybe 59 cm is enough, what you think.
Last column is effective TT,

As you can see I am making budged bike :D just carbon fork frame is Aluminum ... equipment will be sora...

At the risk of grossly oversimplifying... the one that fits is the optimal one. You're not going to find the answer on the internet. Go to a shop and try a couple different ones out.

I am convinced that this is not about the "feeling" more about measuring, arms , torso legs.. etc. Bike that feels good an the first time sitting on it can later start to make problems(aches)