Cannondale Aficionados / Owners

It's shorter. By 3mm. Which is to say it's not really shorter. It's the same :)

I guess there might be some pragmastism going on there involving the re-use of existing designs and molds, along with a recognition that not many people are shaped to warrant a reach much longer than that of the 60cm.

(and if they are they might do well looking at custom)

That said, the CAAD12 doesn't have that feature in the larger sizes.

not many people are shaped to warrant a reach much bigger than that of the 60cm.

It's just poor frame design wrt to fit.

It just seemed counter-intuitive that moving up from 60 to 63 would result in a shorter reach, but when looking closer at the chart there is a difference in seat tube angle too.
The -1 degree seat tube angle (between 58 and 63) cancels out the +2.5 cm in effective top tube length and results in the same reach.

The cervelo article explains it quite well.

Though they were more commenting at the small side of frame building it also applies to larger frames too.

It is why TT length is a poor measure of fit.

This is interesting and I'm trying to understand this, so don't blast me just yet.

But even though (for example) the 58cm and 63cm SuperSix Evo have the same reach, if you were to put the saddle at the same position in the seatpost and run the same length stem, there would still be a 2.5cm distance difference between de tip of the saddle and the middle of the handlebars, right? So you'd still need be taller for the 63cm than for the 58cm, even though they have the same reach?

And doesn't the slacker seattube angle of the 63cm frame increase the distance between the saddle and handlebars even further, between the 58 and 63cm frames? Come to think of it, because the seattube is under an angle, raising the seatpost will increase the distance as well, no?

Isn't the thing with reach is that... it's measured from the BB center.

Which means that two frames with the same reach will have different 'virtual tts', or 'actual real world reach' if their seat tube angle is different.

Is this what you are referring to as poor frame design?

Also I notice that the chainstay length on the larger frames is slightly longer, so is it possible that the BB is pushed forward to further increase the 'real world reach'?

good point, hadn't noticed the seat tube angle change

though given the set back for a saddle is measured in relation to the bottom bracket simply setting the saddle further back by having a slacker seat tube does not actually resolve the fit issue.

Interesting chart +dancing james, it rules out the SuperSix for me then :-(

+Howard Had a Retül bikefit resulting in frame stack/reach 646/409 with a 150mm/-17 stem and 20mm spacers (handlebar stack/reach 689/546).
So, I would really need the reach of the 60cm - but also the stack of the 63 ;-)

What did you parents feed you!??

Kidding. I used to think Stack and Reach was a great way of sizing frames...but when you dig in to it I think it falls down when the angles change across sizes. Maybe.

I think particularly large or small riders, or riders with 'shapes' that aren't typical of their gender need to sling themselves over possible contenders as the numbers don't really work for them.

I'm not super tall, just 189cm - but with kinda long legs and arms.

Of course the fit also includes saddle positioning (for me height/setback = 816/-77mm), and achieving the setback depends on the seat tube angle. So with this in mind, I believe the stack and reach measurements still make sense

But yeah, might be looking at custom then ;-)

130/140mm stem might do it for you

love that!

The Stack and Reach to me revolutionised bike fitting, however you're right about this; the seat angle will need to be taken in account as the massive frames tend to be slacker that the majority of customers end up with their saddle set far forward even with an on-line post.

Ditto to small frame with steep seat tube, massive set back needed.

Yes it's correct, they're designed old skool, meaning frame sizing is a little off.

Fortunately the 2016 hi mod/CAAD12 is designed with Stack and Reach in mind (guy from Cervelo is involved), so they're a better fit.

I wrote it all down here;

https://www.lfgss.com/conversations/248406/

The Stack and Reach to my revolutionised bike fitting

Yes I'm a bit clearer on that now - as long as you have the saddle position relative to the BB it's super useful.

But not so useful if you are just comparing two frames.

Yes, that would probably be the case for me on the Supersix. The bikefit also supplied an effective seat tube angle of 74 degrees, so the 72 degree seat tube would definitely call for a saddle set far forward.

Umm. I just won this on eBay for 20 quid. I don't need or want it and wasn't expecting to win. Anybody want it for that price? I know the colour is a bit... Personal taste but still

1 Attachment

@Dammit need this.

Lulz

Compact?
```

53/39

Doh!

I now have two (2) sets of 53/39 rings (mounted to spiders). I need neither of them.

anodised? painted over? what's the story? could be interested..