Comparing Geometries
 

Hi,

I ride a CAADX 54cm. It's an okay ride, but I've never really loved it since I got it. This past week, I had a chance to ride several miles on a Salsa Vaya 54cm, and it rode like an absolute dream. I don't know how much of the difference I felt is due to geometry and how much is due to the steel vs aluminum.

The CAADX geometry has:
Effective top tube of 53.7cm
Standover 79.1cm
Stack 55.5cm
Reach 37.8cm


The Salsa has:
Effective top tube of 54.0cm
Standover 74.2cm
Stack 59.0cm
Reach 36.5cm

Head tube and seat tube angles aren't shown on the Cannondale site. I also don't know the stem length (or saddle position) for the Salsa that I rode. I will find out though.

It seems strange that the CAADX has a 5cm higher standover but a 4cm lower stack. If that's the case, this seems like it could have a pronounced effect on how a bike would feel. Appreciate any insights.

The CAADX looks like they've done everything possible to have the top tube be as horizontal as possible, the Salsa has not tried to do that. That's where the standover difference comes from. The stack difference looks like it's due to the head tube just being higher up. It looks like it's a good bit more relaxed in terms of fit, would you say that's the case?

Yes. I have a hard time finding the words to tell the difference between these bikes, but I would describe the Salsa as a much "more relaxed" feel than the CAADX. I'm glad to understand how the geometry leads to conclusion about the more horizontal top tube. Thanks.

Does it make more sense to fit by effective top tube or by reach? Of course, ideally I'd fit by test riding a bike, but it's rare that an LBS has every size in stock for a test ride -- especially

The Some Double-Cross geometry: Double Cross Disc | SOMA Fabrications


If I compare the 52cm frame to the 54cm . . . the 54 has a longer effective top-tube, but both have the same reach. I guess this is done by relaxing the seat-tube angle and increasing the head tube length. What does this mean in terms of fitting the bike to a rider?

I'm sure I could fit into either frame . . . but if I'm guided by effective top tube, then the 52cm is close to my current bike. If I let stack/reach lead the decision, then the 54cm is closer.

A steeper seat tube angle (closer to 90 degrees, or more vertical), means that the seat will be closer to the bottom bracket, which would make effective top tube shorter without affecting reach as measured from the bottom bracket.

Likewise, a shallower angle (tilted back towards the rear of the bike more, or less vertical), means the effective top tube length longer, but still not affect the reach as measured from the bottom bracket.

I am by no means an expert, but my interpretation of what it really means for fit is how your center of gravity will be placed relative to the BB. As the seat goes back, your center of gravity goes back for two bikes of the same reach from BB, but you also increase the angle of your chest to your arms, which makes you overall lower.

From what I saw from a quick search, the Salsa has a 1,039.3-mm wheelbase; the CAADX's is 1,014 mm. Maybe the slightly slower handling of a longer-wheelbase bike feels better to you.

You rode a bike that felt better and immediately jumped to geometry/ frame material as the primary sources of difference. Is that true? Same size tires? Similar wheelsets? Cockpit accoutrements?, etc.

I missed why the Salsa was a 'dream'. More stable?, Less twitchy?, Softer ride?, Better position?

edit: More stack, less reach, longer wheelbase (per [MENTION=23624]Trakhak[/MENTION]) = more upright on a sport touring/touring geometry.

+1

For the sake of comfort you want to sit back behind the BB as this takes the weight off your hands/shoulders. The Salsa 54cm has higher stack which is generally considered more comfortable vs a lower stack which is generally considered better for aerodynamics although the truth is more complicated then that.

The 52cm Salsa is pretty much the 54cm with the seat pushed forwards which isn't comfortable for longer distances. If you like the 54cm Salsa stick with it. The differences are primarily in the geometry.

I don't mean to jump immediately into a steel/aluminum debate. We have a few Surly bikes at home, and although they're too small for me, they ride so much smoother than my CAADX that I find myself wanting a ride like that. I want a bike that feels as good or better than that Salsa. If my current bike can do that, then all the better. Add to that, the there is only one Salsa dealer anywhere near my home so I'm okay with taking my time to explore and learn about other options.


To be clear, it's a totally different ride . . . definitely felt more stable AND less twitchy. Softer? I guess. Better postion? I don't really know and need to test ride some more. Some will tell me to stop worrying and just Salsa if I love it that much, but I have some real interest in design and fit.

Direct comparison between these bikes . . . my CAADX has 35mm tires, and the Salsa was stock (which means likely 40mm). Wheelsets? They're both on stock wheels, and I don't have the specs. Cockpits are similarly -- maybe wider drop bars on the Salsa, but the brakes and shifters aren't noticeably different (I didn't spend a lot of time shifting on the Salsa).

It's pretty straightforward when you put it that way. It's just not so easy finding Salsa bikes around my home, so I want to understand what it is about the Vaya that made it feel smoother and better for me. I'm not in a hurry to get a new bike, but I want to be ready if the opportunity arises.

I looked at the 2 bikes in question and given the tire sizes (fat), I doubt the frame material has any impact on ride quality.
I will bow out of the conversation. Roadie here, with any frame that rides more than 30mm tires, i've less experience than you.
Good luck. New bikes are a blast.

Appreciate the insights, and I don't disagree with your assessment about the frame material. Thanks.

In my limited experience I've always felt Cannondale bikes to be overly rigid with an annoying buzzy feel -- the kind of harshness that can't be remedied with fatter tires.

I think what you've experienced is a combination of frame material, geometry and fit. Each contributes to the entire ride experience, and you simply enjoyed the blend.

But what do I know? I'm a steel framed, 72 degree head tube kinda guy. Twitchy handling, buzzy aluminum bikes have never appealed to me. Welcome to the comfortable side of cycling.

-Kedosto

The Salsa has fatter tires, a steel frame, longer chain stays, and taller front end. Very different bike. Less racy, more comfy, more off-road friendly.

If you don't have Salsa in your area, there are gobs of similar bikes like the Kona Rove or Sutra, Specialized Sequoia or AWOL. Raleigh has a whole fleet of them!

Yes! That's the word I was looking for to describe the Cannondale -- it's "buzzy". I've ridden it a lot the last few weeks and kept notes on it and on other test rides I've done. The steel bikes I've ridden are all much more relaxed (by design), and they don't buzz.

Interesting that one of the things that REALLY gets on my nerves with my CAADX is the incredibly loud back hub. It's only an issue when I'm slowing to a stop, which is less than 1% of my riding, but it's really surprising how much that makes a different bike more appealing to me. One of my ideas is to swap out my handlebars for Salsa Cowchppers, get a better saddle, and swap that rear hub for a quieter one . . . that might get my bike close to what I want. But I don't know that making changes like those will make my cyclocross bike comfortable on 2 hour rides.

Yes -- they are totally different bikes. For me, I like to understand what aspects of the design make a bike "less racy" etc. Obviously test-riding is important, but that works better for me if I can understand why a certain bike feels a certain way. The folks at the LBS can rarely explain that to me.


I've found a couple of bikes locally that I'll test ride in the next couple of weeks at the shops. I'll check out Soma, All-City, and Kona. And I watch Craigslist and hope that Raleigh puts up the Tamland again for $799 like they did a few months ago. Plenty of time and plenty of options . . .

Need all the tube lengths, and the joint angles , BB drop , Fork measurements , and wheel diameter, for trail.

essentially a line drawing you could built a frame from , on a big piece of paper..

then you can compare..

CAADX is also a cyclocross bike, which will have a higher bottom bracket than the Salsa, further reducing the standover. The bottom bracket height can dramatically change the handling as well. I'll wager that some of the difference is simple the bottom bracket making the CAADX more twitchy.

Yes. The CAADX has the feeling of being way up off the ground -- likely that bottom bracket height -- which, for me, makes it feel less like a cockpit.