What size bike do I need?

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Kamil1308

New Member
I am trying to buy my first road bike but have no idea about sizing. Everyone I ask has a different opinion. The people in my bike store seem to have no clue or instrest. All the bike fitting companies only do a fitting for bike you already own so that's no help if I don't have one.

I am 5'10 and my leg in seam 32".

TIA
 
Traditionally, bikes were sized by standover clearance. Modern bikes generally have more than enough of this clearance and are sized by reach from saddle to bars. There us some adjustment in saddle (fore-aft) position so reach is a bit of a movable feast, but still one of the most critical dimensions for comfortable riding.

Correct reach for you depends on your body dimensions and your riding stance. As a beginner you might expect to start more upright and gradually ease into a lower/longer riding position over months, if this is what you prefer.

A bike can be fitted to a rider if it is close enough in length by switching the seatpost to one with different lay-back and switching the handlebar stem to one with a different length or height.

As you can see there is no precise formula guaranteed to work.

If your first bike is going to be expensive, try and get hold of a cheaper one of roughly correct size so you can establish a baseline of (dis) comfort.

If you want to read lots of words on the topic you can include this.

https://www.peterwhitecycles.com/fitting.php
 
OP
OP
K

Kamil1308

New Member
Traditionally, bikes were sized by standover clearance. Modern bikes generally have more than enough of this clearance and are sized by reach from saddle to bars. There us some adjustment in saddle (fore-aft) position so reach is a bit of a movable feast, but still one of the most critical dimensions for comfortable riding.

Correct reach for you depends on your body dimensions and your riding stance. As a beginner you might expect to start more upright and gradually ease into a lower/longer riding position over months, if this is what you prefer.

A bike can be fitted to a rider if it is close enough in length by switching the seatpost to one with different lay-back and switching the handlebar stem to one with a different length or height.

As you can see there is no precise formula guaranteed to work.

If your first bike is going to be expensive, try and get hold of a cheaper one of roughly correct size so you can establish a baseline of (dis) comfort.

If you want to read lots of words on the topic you can include this.

https://www.peterwhitecycles.com/fitting.php

Thank you very much for all the info you have.
 

Nebulous

Guru
Location
Aberdeen
Sizing differs a bit from manufacturer to manufacturer, so you can't rely on one size from one company transferring to another. There are also some oddities in the way some companies measure, again making direct comparisons difficult.

I think you would be close to the border between 54 and 56 in most makes. I'm just short of 5' 10 with a 30.5" inseam and ride a 54. General advice is it is easier to make a too small bike fit than a too big one.

As said above I'd get a cheap bike, use it, adapt it (or to it) and use that to inform your decision on the next one.
 
OP
OP
K

Kamil1308

New Member
Sizing differs a bit from manufacturer to manufacturer, so you can't rely on one size from one company transferring to another. There are also some oddities in the way some companies measure, again making direct comparisons difficult.

I think you would be close to the border between 54 and 56 in most makes. I'm just short of 5' 10 with a 30.5" inseam and ride a 54. General advice is it is easier to make a too small bike fit than a too big one.

As said above I'd get a cheap bike, use it, adapt it (or to it) and use that to inform your decision on the next one.

Thanks for the reply. Atm I am using freinds bike I have done 2 40km cycles with no problems. Will go for 70km one over this weekend. Should I keep riding his for a while and then if I am okay on it get something similar dimensions. I am looking into getting giant advanced tcr 1 but am stuck between m or m/l. Would I be better off getting m rather then m/l.
 

Nebulous

Guru
Location
Aberdeen
Thanks for the reply. Atm I am using freinds bike I have done 2 40km cycles with no problems. Will go for 70km one over this weekend. Should I keep riding his for a while and then if I am okay on it get something similar dimensions. I am looking into getting giant advanced tcr 1 but am stuck between m or m/l. Would I be better off getting m rather then m/l.

I've never had a Giant bike, but going by this you would be a medium. (Click on the what is my size link.) What kind of bike have you borrowed from your friend, and what size is it? Is there a Giant dealer nearby where you can try one?
 
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