19 inch - is that 19 inches from bb to top of seat tube?

Aud Reekie MTB

Hey,

As above really - is that the common way to size a mountain bike?

ta

Andy

nicklouse

it depends on who has made the frame.

some measure BB center to top of seat tube. some measure BB center to where the center of the top tube crosses the seat tube. and there are also many other ways that they are measured.

All it is is a means to show that the version of this frame is bigger or smaller than another one.

And does not mean that one brands 19's are the same through the frame range.

Aud Reekie MTB

Cheers Nick

(apologies about the double post earlier! :oops: ).

Am looking at at Scott Scale 35, which is 18.9 inches from bb to top of seat tube, with 30.5 inch standover height, as per their website.

That would leave me 2 inches standover height (baw gap ). Does that sound about right?

dave_hill

Inside leg measurement minus 14" should give you an idea of frame size, BB to top of seat tube.

nicklouse

dave_hill wrote:

Inside leg measurement minus 14" should give you an idea of frame size, BB to top of seat tube.

interesting measurement, but would not work for me would make my bikes way too big, Yes the XC ones.

supersonic

dave_hill wrote:

Inside leg measurement minus 14" should give you an idea of frame size, BB to top of seat tube.

Is a pretty poor way of doing it.

The Spiderman

Top tube lenght has much more efect on how big a bike feels.
The only way to know is to try them,for size.

dave_hill

supersonic wrote:

dave_hill wrote:

Inside leg measurement minus 14" should give you an idea of frame size, BB to top of seat tube.

Is a pretty poor way of doing it.

For what reason? Explain please, you accused me of making sweeping statements in another post.

It always worked for me. I have an 33" inside leg, so les 14" is 19". Which oddly is just about the best size for me. Weird eh?

In any case, I didn't claim that it's a hard and fast rule. I actually prefer a smaller frame as I like to sit more upright, but this method never failed for me in over 20 years.

supersonic

You have not taken into account any other measurements! Given a certain model of bike lets say:

I am 6ft with a 34 inside leg. So I need a 20" frame by your reckoning. However I may have a short upper body length because of my long legs and prefer a shorter reach. The frame is far too big.

My mate is 6ft with a 30 inch inside leg. So he needs a 16"? But he has very long arms! The frame is too small.

Have a read of the What Size sticky thread. Far too many variables for this method, but of course it may just happen to work for some people.

Of my three current bikes: the Zaskar LE is 20.5inches, the Team 18.5 inches and the Ruckus 17 inches.

dave_hill

supersonic wrote:

You have not taken into account any other measurements! Given a certain model of bike lets say:

I am 6ft with a 34 inside leg. So I need a 20" frame by your reckoning. However I may have a short upper body length because of my long legs and prefer a shorter reach. The frame is far too big.

My mate is 6ft with a 30 inch inside leg. So he needs a 16"? But he has very long arms! The frame is too small.

Have a read of the What Size sticky thread. Far too many variables for this method, but of course it may just happen to work for some people.

Of my three current bikes: the Zaskar LE is 20.5inches, the Team 18.5 inches and the Ruckus 17 inches.

Yes, I understand that it doesn't take into account other measurements.

But at what point did I say, "Using my method will work perfectly and give you the exact frame size you need?"

I didn't, did I? Because it won't. Read my post again...

dave_hill wrote:

Inside leg measurement minus 14" should give you an idea of frame size.

The crucial bit is that it will give you an idea. Yes perhaps I should have added a caveat that it's only a staring point and may not work for everyone.

supersonic

But at what point did I say, "Using my method will work perfectly and give you the exact frame size you need?"

You didn't, nor did I accuse of that. I just think it can throw up some very strange measurements given the vast array of geometries, bike types, brands, measuring standards, people and riding styles. In the past 15 years I have ridden bikes from 14 to 22 inches in 'size'.

Aud Reekie MTB

Andy lit the blue touch paper then retired!