# Calling on all LOOK experts - help with 585 sizing



## guerciottiman (Feb 25, 2005)

Hi All,

I've been a lurker on this fine forum for a while and have now decided to write my first post. I have finally given into temptation and decided I will spoil myself with a LOOK 585 in Pro Team guise.  This will be my first foray into the LOOK experience. 

I thought that I had my sizing figured out based on what I am riding now and the rough estimate I got from the Wrenchscience fit calculator. My body numbers are roughly:

Measurements
-------------------------------------------
Inseam: 87
Trunk: 63.5
Forearm: 35
Arm: 72
Thigh: 62
Lower Leg: 56
Sternal Notch: 148

I currently ride a classical geometry 55 TT with 12cm stem and a BB-top of seat approx 75.5cm. Wrenchscience recommends 55.5-56 TT with a 11-12cm stem and approx 77cm BB-top of saddle.

Based on these numbers I had made up my mind that a size L (56 TT) would be a great fit for me. But as I researched more I am no longer sure. I have read that some people with similar dimensions to me are on size M (54.5 TT) frames. 
So what gives am I being paranoid or should I go for the L size? Given my measurements do you think that I could fit either M or L?
I'd appreciate any advice.

Unfortunatley, I do not know of any Look dealers here in Canberra, Australia to get a proper fit.

Sorry for the long post and thanks in advance.

Cheers!


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## Roy - DK (Nov 3, 2006)

guerciottiman said:


> I thought that I had my sizing figured out based on what I am riding now and the rough estimate I got from the Wrenchscience fit calculator. My body numbers are roughly:
> 
> Measurements
> -------------------------------------------
> ...


Hi, I can't tell you what to choose.
But I can tell what I did here in Denmark.

I went down to one of my local LBS's and bought a complete professional messuring - a system caled; Body Scanning - that cost appox. 65,- us$.= - 400,-Dkr. and I got the messurement scheme with me back home for further investigations of different frames.

The system also gives you the messures of these parts :
Stem lengthe, position and height of the saddle, Crank lenght and so on.
But ofcause they are not definite, but the tollerances are ther too.
And after assemblying the bike the LBS include a check up for the bikes adjustment.

After that I asked arround and was told to choose from the length of the TT need, While the rest can be adjusted in the length of the different parts.

That worked out for me, I'm now the happy owner of a 585 Ultra size XL, and looking forward to the Spring season.

Roy


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## C-40 (Feb 4, 2004)

*need more info...*

I would NEVER rely on the recommendations of any online fit calculator. None are accurate enough to be of much value.

That said, your saddle height does seem on the low side (for an 87cm inseam), but to a large extent it depends on the "natural" angle of your foot while pedaling. A rule of thumb is that your foot should be about horizontal with the leg locked out at the bottom of the stroke. Then a 2-3cm rise of the heel while pedaling will result in the optimum 30 degree angle between the upper and lower leg at the bottom of the stroke.

As for selecting the size of 585 that will best duplicate the fit of your current bike, that's easy if you post more info. You need to post the seat tube angle, because the TT length alone does not define the frame's reach, which affects stem length. Then you need to post your desired handelbar height, measured vertically from the floor to the top of the bars. So far, you've only concerned yourself with the TT length and haven't consider the head tube length.

Based solely on your inseam, the 55cm would be the correct size, but based on your saddle height, the 53cm might be useable. What you want to avoid is an odd stem and spacer setup. Before buying one, I'd want to know exactly what stem length and angle were required and how much steering tube spacer was needed to get the desired handlebar height.


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## guerciottiman (Feb 25, 2005)

*Here is the extra info*



C-40 said:


> I would NEVER rely on the recommendations of any online fit calculator. None are accurate enough to be of much value.
> 
> That said, your saddle height does seem on the low side (for an 87cm inseam), but to a large extent it depends on the "natural" angle of your foot while pedaling. A rule of thumb is that your foot should be about horizontal with the leg locked out at the bottom of the stroke. Then a 2-3cm rise of the heel while pedaling will result in the optimum 30 degree angle between the upper and lower leg at the bottom of the stroke.
> 
> ...


Thanks for the feedback C40 - much appreciated. I agree with you that online fit calculators are not to be taken as gospel. They can be useful to point you in the right direction though. The fine tuning should be done on the bike!
Also, a correction on my inseam measurement: 86cm - my misprint.
The additional info for my current bike is: Seat tube angle:73.45; Head tube angle: 73.3 and top of handlebar to floor is about 91.5cm (which includes a head tube length of about 17.5cm with H/set).
Thanks again, I'd be intrigued to get your thoughts on whether I should go for the M or L or either and can fine tune either once I get the frame.

Cheers!


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## C-40 (Feb 4, 2004)

*more advice..*

The large (55cm) is the size to get. It will require one size shorter stem. To get a handlebar height of 91.5cm, you'll need a total head tube length of about 190, with the headset and spacers, using an 84 degree stem. On the large size frame the head tube is 156mm and the top section of the headset is 15mm, so you'll need 20mm of spacer to get a length of 191mm. The head tube would be much too short on the smaller 53cm frame.


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