Geometry question, advice
 

Hi! I have a question regarding the geometry of two bikes.

I'm very comfortable with this geometry in size 52 (Cannondale). The fit is great and I can ride long distance rather comfortably.
http://i253.photobucket.com/albums/h...ps0466ef2c.jpg

I'm having issues with this geometry in size 49 (Kona). My current fit is not as good.
http://i253.photobucket.com/albums/h...ps1a5b5c9f.jpg

I would like to hear some advice in terms of what to try first in order to improve the fit of the Kona bike and hopefully get closer to the Cannondale fit.

Both bike have the same saddle. The Kona bike has a shorter stem (same angle) and I am guessing this is the first thing to try... a longer stem, likely 1cm longer. But I'm not sure.

I'm trying to better understand my body and how to modify the components accordingly. So I would rather try a few things on my own right now instead of going for a professional bike fit. Ideas are appreciated. Cheers!

Can you define "not as good"? There are so many things that can be "not as good" it's impossible to give even half-reasonable answers without knowing what "not as good" means. Too long, too short, feels cramped, neck sore, whatever, just do a stream of consciousness reply, just type whatever comes to mind as different between the two bikes.

Also what stem length/angle on each frame. How far back is the saddle (from BB or on seat post)? What type of post, set back or no set back? Saddle-BB height the same between the two? Crank length? Pictures of the two bikes from the side would help the obvious become obvious.

I have some of the measurements, but not all of them. I'll get back shortly.

The first thing you need to do is get the saddle position on your Kona to match the position on your Cannondale.

Height from BB center, and the amount of setback from BB center. Once those are the same, then you can work the bar position.

Measurements = revelation, duh!


What stem length/angle on each frame?
Cannondale = 10cm, 6 degrees
Kona = 8cm, 6 degrees

How far back is the saddle (from BB or on seat post)?
Cannondale = 4.5cm saddle nose back from BB
Kona = a bit over 1cm saddle nose back from BB

What type of post, set back or no set back?
Both set back

Saddle-BB height the same between the two?
Yes, same on both = 69cm

Crank length?
Yes, same on both = 17cm

Pictures of the two bikes from the side would help the obvious become obvious
Pics will take a bit more time


With these measurements, I am realizing that the Kona setting is too short. Is this a fair assessment? Likely matching the set back and then getting a longer stem (1cm longer might do it) is the way to go. Thanks!!!

I have two bikes with slightly different geometries (my main ride is a size 52 CAAD10). When fitting myself to a new bike I try to keep everything the same from my previous bike. My priority is the saddle-BB height and the saddle fore/aft position, next is the handlebar reach (the frame's "reach" measurement + stem length), and finally the handlebar height (combination of the frame's "stack" measurement + height of stem/spacers + stem angle).

Replicate everything on CAAD to the Kona first (saddle position, stem length - (swap them?) ) then try it out. The Kona's headtube angle is shallower than the CAAD's so the replacement stem might be longer than 100 mm.

I found this and it helps to visualize what's going on when comparing two bikes: http://gearinches.com/blog/misc/bike...try-comparator

All you have to do is compare the reach and stack to know that the two frames are nearly identical. Even the STA is the same.

As others noted, start with the saddle height and setback. The Kona should use the same stem length as the C'dale, unless you have bars with with a different reach and/or brake hoods with more reach one of the bikes.

Yes, I think this will do it. Thanks for the help!

Wow, very detailed. Thanks!