Mk3 Audax sizing

[touringcyclist853]

Hello,

I am in the market for a Mk3 audax frameset (one of the last few left!) or possibly a full bike build from SJS and have been recommended the 525 frame with the 46mm rake forks by SJS.

I currently ride a fairly basic commuter bike (2018 Trek FX2 20'' frame) and my saddle height is 86cm with my current ETT being just shy of 57mmm with a 100mm stem fitted and the standard Trek flat bar (all be it with a slight rise in the bar).

The 525 audax frameset has an ETT of 55cm which sounds about right to me given my experience over recent years trying out off the peg drop bar audax style bikes, all of which felt slightly too large to me (an example being a size Medium Genesis Equilibrium of 3 years ago).

I'm 5'10'' in height too. 

Given that I will not have the opportunity to go and try before I buy any time soon, can anyone give me some pointers, advice or information about they're own bike fit?

Many thanks,

Mark

[leftpoole]

You need 550
John

[touringcyclist853]

Many thanks for your reply. Much appreciated.

[PH]

My advice - Go with Thorn's recommendation, their experience will be based on thousands of bikes rather than the handful anyone on here will have experienced.  Then ride it a thousand miles before changing anything, test riding unfamiliar bike types is not a good way of deciding - the familiar will feel right, even if it isn't. 
Perfect fit is important, but with many bike models that can be achieved over more than one size frame.  The critical measurements are between the pedals and the saddle, both height and fore/aft. If you find the sweet spot here, then the bars just become somewhere to rest your hands, easily adjusted for personal preference with stem and bar choices.
My own bikes vary from 57 to 61, set up to ride comfortable audaxes on any of them.

[JohnR]

Have you read through the frame sizing section (page 25 onwards) in the Thorn bible http://www.sjscycles.com/thornpdf/thorn_mega_brochure.pdf ? I'm 5' 7" and have a 55L Mercury with straight bars but did have to replace the provided 110mm ahead stem to 80mm as I've got the saddle well back to try to comply with the KOPS rule. I'm surprised by your saddle height as mine is about 96cm from ground level. This affects the reach to the handlebars as a higher saddle is further back. You might want to check if raising the saddle on your current bike makes your legs feel more efficient although, if the handlebars are too low then the position might not be comfortable.

[energyman]

I was "bike fitted" years ago by SJS for my RST.  They got it absolutely dead right, never had to change anything on the bike 'cos it fits like a glove.
All my other bikes are modeled on the RST dimensions as far as possible.
I am under the impression they know exactly what they are doing !

[leftpoole]

I am 5ft 7ins. I have had and own 550M which is a perfect size.
No way would someone of the height/size opening poster be able to use a 525. In this case someone is talking rubbish!
I am trying to help. I always get shot down. What is the point?
Get on with it, buy the wrong size bike-who cares?
To those pointing out the size of Rohloff type bikes, it is totally different. No way would an Audax be fitted with the stupid high rise bars suited (?) to those bikes.
Try deleting this-if you dare!
John

[leftpoole]

My advice - Go with Thorn's recommendation, their experience will be based on thousands of bikes rather than the handful anyone on here will have experienced. }




Nonsense!