Bike fitting - riding a 52cm frame

A light bike doesn't replace good fitness.

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octav
Posts: 145
Joined: Thu Aug 27, 2009 12:40 pm
Location: Bucharest/Romania

by octav

Hi,

I'm 1.76cm and 64 kg. I'm currently riding a 52,5 cm top tube frame with 50 cm seattube and 13.5 cm headtube lenght.
I'm running a 3 cm setback seatpost.

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What do you think of my bike fitting? I feel pretty good with the bike but I think maybe I should get a 54 cm frame(the last frame was a 54 with a 12 cm stem and 2 cm setback seatpost).

The bike fitting is:
Tip of Saddle to center of Bars : 55.5 cm
C of front hub to top of bars : 57cm
Saddle height: 74.5 cm
Top tube: 52,5cm
Stem : 13 cm

by Weenie


audiojan
Posts: 785
Joined: Fri Jan 27, 2006 1:38 pm
Location: New Hampshire

by audiojan

From that angle it's almost impossible to tell how your fit is. You need to have two angles (and preferably a video), side perpendicular to bike and front view. Side view should include bottom of pedal stroke.

A few things I suspect though... your seat might be too low and you are pretty cramped up on the bike (too short reach).
"Suddenly the thought struck me; my floor is someone elses ceiling" - Nils Ferlin

octav
Posts: 145
Joined: Thu Aug 27, 2009 12:40 pm
Location: Bucharest/Romania

by octav

Another 2 pictures

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hope they help a little

Krull
Posts: 775
Joined: Thu Dec 18, 2003 1:16 pm
Location: muc

by Krull

octav wrote:Hi,

What do you think of my bike fitting? I feel pretty good with the bike but I think maybe I should get a 54 cm frame(the last frame was a 54 with a 12 cm stem and 2 cm setback seatpost).

The bike fitting is:
Tip of Saddle to center of Bars : 55.5 cm
C of front hub to top of bars : 57cm
Saddle height: 74.5 cm
Top tube: 52,5cm
Stem : 13 cm


i think the bike fits-of course, you could get a 54 with a shorter stem, but i think, it wouldnt make a significant difference. maybe, it would be a little more harmonious, because a 130 stem seems to be quite long for a 525 top-tube. furthermore you could leave out one or to spacers.

my height is 172 cm, but i am extremly "leggy", my inside-leg is 85 cm!

my bike fitting is:
Tip of saddle to center of bars: 54 cm
c of front hub to top of bars: 55 cm
saddle height: 74,8 cm (very flat shoe/pedal-system:look keo carbon with adidas adistar ultra)
top tube: 52,8 cm
Stem 110 (10°)
sorry vor mai bed englisch!

octav
Posts: 145
Joined: Thu Aug 27, 2009 12:40 pm
Location: Bucharest/Romania

by octav

Thanks Krull. I feel pretty good on the bike but I think I have a little birdy in my head that says to me I need a 54cm frame and lighter wheels :)) Probably it's fine like this.

denzity
Posts: 96
Joined: Sun Mar 27, 2011 10:01 pm

by denzity

You look okay, though it's hard to tell from pics. For me the most important thing is stem length.

I'm 173cm and have 52cm, 54cm and 56cm bikes (great bargains!) and ride all three regularly without noticing that the frame is a different size. However, it took me about 6 or 7 stem changes before I got the reach right so that it's exactly the same on each one.

So, like you said, it's probably just in your head that you need a new frame. Then again..... it feels good to buy new bike parts :D

octav
Posts: 145
Joined: Thu Aug 27, 2009 12:40 pm
Location: Bucharest/Romania

by octav

For the moment I think I'll buy another handler ( with less reach) to see what's the difference. And i'll borrow a 140 mm stem from a friend :D

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euan
Posts: 1499
Joined: Sat Sep 05, 2009 11:20 am

by euan

I think certainly your seat height is too low. You are almost hanging your butt off the back of the bike and that is usually a sign of the body looking for length to stretch your hamstring.
"Step forward the climber and all those who worship at the altar of lightness" - R. Millar

ghisallo2003
Posts: 600
Joined: Mon Jan 02, 2006 7:10 pm

by ghisallo2003

My first question - do you ride with a club or team? If you do, then the old heads there should be able to give you some pretty good advice. I would turn to these guys rather than pay for fitting.

This said, I think your frame is too small, based on both your measurements and your photos, as has been observed. It is not a disaster, but I would definitely start the process of trying to find one that fits and working out how to do this within your budget. Whilst young it is worth getting your body into good position habits, rather than having to do this later on.

I know this invites plenty of people to give their measurements and tell how successful they are, but a 52cm frame with 140mm stem sounds plain wrong. For both aesthetics and handling frame sizing and stem length should go up hand-in-hand. Stem length is a way to make small changes rather than address a wrong sized frame. Your 3cm setback sounds small for your height, and this is reflected in your body seeking to sit far back on the saddle.

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Roobay
Posts: 1958
Joined: Fri Mar 23, 2007 12:19 pm
Location: On Pave

by Roobay

euan wrote:I think certainly your seat height is too low. You are almost hanging your butt off the back of the bike and that is usually a sign of the body looking for length to stretch your hamstring.


+1 leg not fully extended at the bottom of the pedal turn, maybe be a offset seatpost, with extra height :thumbup:
i like people... i just can't stand assholes

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euan
Posts: 1499
Joined: Sat Sep 05, 2009 11:20 am

by euan

When you said its a 3cm set back seat post do you mean the seat post has 3cm of set back or your saddle nose is 3cm behind the bb?

If its the later then that sounds a bit small too.
"Step forward the climber and all those who worship at the altar of lightness" - R. Millar

octav
Posts: 145
Joined: Thu Aug 27, 2009 12:40 pm
Location: Bucharest/Romania

by octav

The seatpost has a 3cm offset. I didn't measure the setback yet. I will measure it and post it. I'll do a longer ride tomorrow with a higher saddle to see what it's happening.
I don't belong to a club but ride with some guys that do this for a living. I asked them and they said that I should do it like I feel best. But this isn't the best advice :lol:

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euan
Posts: 1499
Joined: Sat Sep 05, 2009 11:20 am

by euan

don't increase it too much. 1cm to begin with.
"Step forward the climber and all those who worship at the altar of lightness" - R. Millar

octav
Posts: 145
Joined: Thu Aug 27, 2009 12:40 pm
Location: Bucharest/Romania

by octav

I increased it exactly 1 cm today and it's much better. I did 150 km and legs are not hurting so I think it's ok. I feel a little bit the need to get back on the saddle but not that much anymore. Should I get it a little bit higher. I'll measure the setback today and post it.

Krull
Posts: 775
Joined: Thu Dec 18, 2003 1:16 pm
Location: muc

by Krull

ghisallo2003 wrote:
I know this invites plenty of people to give their measurements ......


...which would be very desirable, i really find it very interesting, to compare my position with those of other riders.
sorry vor mai bed englisch!

by Weenie


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