CAAD10 Frame Sizing

[mjth2004]

I have eventually decided that a Cannondale CAAD10 is the frame for me to build! I have taken on board that it’s better to ride a high-end aluminium frame over a low-end carbon fibre.

Just before I order the frame I have a question regarding frame sizing & if someone could offer feedback on my thinking before I make the purchase I would be most grateful.

I have been professionally measured up for both a tt bike & a road bike, on the road bike I was given a stack height of 59cm & a reach length of 36cm (with a 110mm stem) that will suit my body geometry.

The CAAD10 geometry is here:

http://www.cannondale.com/irl/2011/bike ... 10-ultegra

My thinking is that the 58cm frame will fit me. Reason being the stack height of 57.9cm will leave me with just one 5 or 10mm spacer below the stem & reach length of 39.9cm will require me to ride with an 80mm stem.

Am I right in thinking the above or should I size down, if I need to size down what would be the reason?

[natiedean24]

If getting proper reach requires an 80mm stem, you should consider going with a smaller size frame and longer stem with more spacers to compensate for the decrease in stack.

[mjth2004]

I've been looking at some of the pro-team set-ups & have seen most now ride with a zero spacer or just the minumum spacer! So trying to set up similar on new frame plus with a fork steerer isn't there only a certain height you can have until it becomes a structural issue!

[djconnel]

I've been looking at some of the pro-team set-ups & have seen most now ride with a zero spacer or just the minumum spacer!

I wouldn't worry about that.

[daj]

You're probably not a pro, so don't compare yourself to them. By the way there are plenty of pro riders with considerable amount of spacers and even stems pointing upward.

But anyway, let's calculate.

If you use a 110 stem (-6 degrees and 0 spacers I assume for this case) with a 360 reach 590 stack frame, you require a handlebar reach of 457 and stack of 645.

To achieve roughly the same position on a 58 cannondale that would translate into 15mm spacers, 80mm stem at -6 degrees.
On a 56: 35 mm spacers, 90mm stem at -6 degrees.

[natiedean24]

If you wanna have a pro-like setup, focus on getting a frame that is properly sized so that your weight distribution and stem length work to make the bike handle as best it can.

I'm worried that an 8cm stem is a bit short and will negatively affect the handling. If I understand, a shorter stem would make an already fast handing bike more twitchy.

I don't know what the difference in stack is between 58 and 56, but I would think that you could substitute that number of spacers and still be safe with the steerer tube.

What stem are you planning to use - a -6 degree type? You could always flip that and get a bit more than 2cm of lift that way. It doesn't look that bad.

[mjth2004]

You're probably not a pro, so don't compare yourself to them. By the way there are plenty of pro riders with considerable amount of spacers and even stems pointing upward.

Far from it - sure if I had the pro status I wouldn't need to be worrying about these things as the support team would just sort it all out & tell me to ride!

Cheers for taking the time to reply!

As for weight distribution on a frame - I haven't a clue! I am a 5' 09'' 64kg with a FTP of 245 Watts if that makes a difference on distribution!

[daj]

As you are 5'9, do you have long legs? What is your saddle height? Anyway, with your height, a 58 frame I think is definitely way too big. I'd look for a 54 or 56 depending on the length of your legs.

[lwrncc]

I'm 5'9 (176cm) and I can't imagine riding a Cannondale in 58. Who was fitting you?

I ride a 52 Tarmac with 110mm stem for reference. Good luck with your fit.

[jmilliron]

Yeah, I'm 6'1" on a 58 CAAD10. I can't imagine someone four inches shorter riding one.

[RussellS]

I am 5'11" on 58cm CAAD7 and CAAD9. With 12cm stems and setback saddles. So at 5'9", you need a 56cm frame. Probably with a 11cm stem.

[mjth2004]

I have been fitted off a Boardman Team Carbon, where my ideal road bike positioning was dialled in! The fitter is qualified under the F.I.S.T system.

Saddle height from centre of BB, parallel to the seat tube is 78cm & I ride 172.5mm cranks.

Think I sort of understand, yes the stack & reach of the 58cm would suit but between using a short stem (poorer road handling) & weight distribution (don't fully understand so still researching) at the stack height. So on that the 56cm might be a better fit, but would there be that much difference between 58cm vs 56cm?

@Jimilliron - what spacer depth / cockpit set up are you running?

[djconnel]

I think the weight distribution thing is over-rated. Small differences in seat position have a bigger effect, or for that matter body position on the seat. Same deal with the steering moment. The steering moment has far great influence from handlebar width than from stem length.... even handlebar reach has a comparable effect to stem length. So I admit I don't understand the aversion to 80 mm stems.

But oversized frames will be heavier and people will look at you funny for riding such a large frame. I think the latter is the more important to most people, frankly.

[daj]

I'm about 5'9 too and my seat height is 73 so that's a big difference in leg length! Usually with long legs you'd also have long arms so I don't really understand the short reach you require. Anyway I ride a 393 reach frame with 100mm stem, handles great!

[semaj]

I am 5'11" on 58cm CAAD7 and CAAD9. With 12cm stems and setback saddles. So at 5'9", you need a 56cm frame. Probably with a 11cm stem.

I'm really curious to see how you fit on that frame. I'm a half inch taller than you and I ride 56cm CAAD10 with a 12cm stem, 100mm drop, and saddle on a setback setup on the middle of the rails.