First road bike sizing
#1
Thread Starter
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Joined: Dec 2016
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First road bike sizing
Hello, new member here. I imagine this question gets posted OFTEN, but thought I'd try nonetheless 
I'm looking to get my first road bike and I'm having a few sizing issues. I'm 184cm in height, 86cm inside leg and arm span of 182cm, which I think leaves me between a 56 and 58cm frame, depending on specific geometry(?). Certainly seems to be the case with the bikes I've tried out in shops.
I'm thinking of getting a Merlin performance PR-7, which unfortunately is pretty much the top of my budget (returned to being a student!). Their sizing gives me an option of 56cm or 59cm, which I'm a little unsure about. Unfortunately I'm too far away to test. Specific geometry is attached, but to summarise:
Frame Size option: 56 59
Seat-tube (centre - top): 560 590
Effective top tube: 550 560
Any advice, or experience with these specific bikes much appreciated!

I'm looking to get my first road bike and I'm having a few sizing issues. I'm 184cm in height, 86cm inside leg and arm span of 182cm, which I think leaves me between a 56 and 58cm frame, depending on specific geometry(?). Certainly seems to be the case with the bikes I've tried out in shops.
I'm thinking of getting a Merlin performance PR-7, which unfortunately is pretty much the top of my budget (returned to being a student!). Their sizing gives me an option of 56cm or 59cm, which I'm a little unsure about. Unfortunately I'm too far away to test. Specific geometry is attached, but to summarise:
Frame Size option: 56 59
Seat-tube (centre - top): 560 590
Effective top tube: 550 560
Any advice, or experience with these specific bikes much appreciated!
Last edited by SC_C; 01-03-17 at 02:25 AM.
#2
Senior Member
Joined: Apr 2005
Posts: 10,879
Likes: 6
From: Northern California
IMHO - top tube length is more important than seat tube length for fitting, especially in the bigger bike sizes. Some people want a longer lower riding position and others want a shorter more upright position. Your arm length and core strength also affects this decision.
#4
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Joined: Jun 2010
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From: NW,Oregon Coast
Bikes: 8
+1, go with an in Person test ride for Your first Bike , what you learn from that will guide what you want different for your 2nd.
[I own a 56, 57 & 58 (& a 54 and some folding Bikes & a MTB) fwiw]
But the Look now of the TDF riders is Not the Fit I prefer .. Horizontal Top Tube C&V type road Bike, for Me. 5'9"ish 565~ 570 top tubes 9, & shorter stems..
YMM(obviously)V
[I own a 56, 57 & 58 (& a 54 and some folding Bikes & a MTB) fwiw]
But the Look now of the TDF riders is Not the Fit I prefer .. Horizontal Top Tube C&V type road Bike, for Me. 5'9"ish 565~ 570 top tubes 9, & shorter stems..
YMM(obviously)V
Last edited by fietsbob; 12-31-16 at 04:01 PM.
#5
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Joined: Dec 2004
Posts: 15,394
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From: Seattle area
Bikes: Bikes??? Thought this was social media?!?
I am just a bit larger than you. 186 tall, 88 leg, 190 arm span.
my range of comfort is 59 - 62cm frames with a top tube nominally 58cm + 12cm stem.
Either frame could likely fit, but the tt measurement of 55cm seems a bit short. With the sloped top tube, the 59 frame certainly isn't too tall and only 1cm greater in ETT.
Sorry I do not know the bicycles in question.
+1 to earlier recommendation on 1st road bike = ride a few before deciding. This is where a decent bike shop can make you happy and save money in the long term.
my range of comfort is 59 - 62cm frames with a top tube nominally 58cm + 12cm stem.
Either frame could likely fit, but the tt measurement of 55cm seems a bit short. With the sloped top tube, the 59 frame certainly isn't too tall and only 1cm greater in ETT.
Sorry I do not know the bicycles in question.
+1 to earlier recommendation on 1st road bike = ride a few before deciding. This is where a decent bike shop can make you happy and save money in the long term.
__________________
Vintage, modern, e-road. It is a big cycling universe.
Vintage, modern, e-road. It is a big cycling universe.
Last edited by Wildwood; 12-31-16 at 03:32 PM.
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