Road frame sizing

[rider]

Hello!

Please don't beat me (it must been posted thousand times before)!
If I have 18" MTB frame (46cm from center of bottom bracket to top of seat tube) that fits to me, Is there any rough ruling what size of road frame will fit?

Thank You!

 

[Tel]

Old rule was your inside leg minus 10". It's about right for me.

 

[NeilM]

Old rule was your inside leg minus 10". It's about right for me.

That would have me riding a 63.5 frame, where as I actually ride a 56 :shock:

 

[Tel]

Blimey! I ride a 56cm and have "regular" size inside leg! Do you have long legs short arms?

 

[NeilM]

I don't think so. I'm just over 6' 1" with a 35" inside leg.

My son is pretty much the same height and build (only younger, slimmer and fitter damn him) and is the real roadie around here, I took my cue from him, as he's been to Bike Science with his Boardman for a pro-fit.

I could ride a 58 or even a 60, but I would need a short stem or short top tube on either.

I also ride smaller mtbs, 17.5" to 18" as opposed to 19 or 20" which is what convention says I should be riding.

Let's face it, I'm just odd :roll:

 

[Old Ned]

I don't think so. I'm just over 6' 1" with a 35" inside leg.

My son is pretty much the same height and build (only younger, slimmer and fitter damn him) and is the real roadie around here, I took my cue from him, as he's been to Bike Science with his Boardman for a pro-fit.

I could ride a 58 or even a 60, but I would need a short stem or short top tube on either.

I also ride smaller mtbs, 17.5" to 18" as opposed to 19 or 20" which is what convention says I should be riding.

Let's face it, I'm just odd :roll:

Is it a 'compact' (sloping top tube) or 'conventional' (flat TT)? This can make a massive difference in frame size.

 

[gregs656]

I used this guide;

http://www.competitivecyclist.com/za/CC ... ATOR_INTRO

Which I found useful. Gives you different options depending on how hardcore you want your riding position to be.

I hadn't heard the inseam - 10" thing, but that is consistent with this guide, and my bike.

 

[NeilM]

Is it a 'compact' (sloping top tube) or 'conventional' (flat TT)? This can make a massive difference in frame size.

His is a full carbon thing, with sloping top tube.

My Raleigh is a 1999 model RSP in Reynolds 853 with a slightly sloping top tube. My other bike (which I've not ridden yet) is a 1980's Concorde with a straight top tube.

Neither have any more than a fistfull of seatpost showing, where as the boys Boardman has a seatpost like an mtb.

EDIT:

That's a cool link.

Using some quick body measurements, I am very close to my ideal competitive fit. My frames are a little short in the top tube, but saddle height and several other of the bike measurements are within a few mm of their recommended dimensions.

As for the French or Eddy fit, my bikes are way too small, but then I'm not French and I am most definitely not Eddy.

 

[rider]

Thanks to all of You! Now it will be easier to decide which road frame size for mine training.

 

[Iwasgoodonce]

Remember, the important dimension for road bike fit is length. Use the excellent advice above and when sat on the potential purchase with your hands on the hoods, look down.

Can you see the front hub? If the answer is no, the bars are in the way, the length is about right!