The seat stays on my brand new Cannondale CAAD12 frame are slightly warped (not straight and slightly different on both sides), especially around the welding spots for the rear brake mount. I could imagine this could be because of the heat treatment, but just want to make sure, is this normal?

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Full res picture: https://drive.google.com/open?id=0B9y6l6S7soQvLWtZVFg2RXdOMUk Thank you!

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    Are you sure it isn't part of the design of the bike? You should give a picture to describe what you're looking at. – Batman Jun 14 '16 at 20:47
  • Thank you for your quick reply. I assume it isn't part of the design since both sides are slightly different. Just off by let's say a millimeter or so. But when looking along the length of the tubes (so from the top kinda) you can see there is some little warping going on, which like said before is slightly different for the left and the right seat stay. Can't take a picture right now unfortunately. – user26457 Jun 14 '16 at 21:10
  • I made pictures: drive.google.com/open?id=0B9y6l6S7soQvLWtZVFg2RXdOMUk – user26457 Jun 14 '16 at 21:54
  • For a second there I thought that was a mirror :) – BSO rider Jun 15 '16 at 0:19
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    Can you look at another CAAD12 in a shop or something? I can't make anything out of the pictures. – Batman Jun 15 '16 at 0:29

You are concerned that something is wrong with the frame. You can check the alignment by getting the Park FAG-2 alignment tool or, and it comes to the same thing, measuring to see if the distance to the seat tube is the same on both sides using a string - a string test. If you feel uncomfortable running a string from the rear dropouts around the head tube and measuring the distance from the string to the seat tube on both sides, then get the Park tool. Otherwise, run a string and measure. string test If the measurements are identical, then the seat stay "warping" is purely cosmetic - the frame is properly aligned. If the frame is off, then you are warned not to try cold setting thin aluminum tubes. I have to admit here that, if I got a really good deal on the frame and it was only off a little, I would be tempted to correct it. See the Park FAG-2 link for other ways of dealing with it in case you find that the frame is off a little.

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    Could you possibly edit this to answer the question? The Sheldon link is to re-spacing dropouts, not straightening chainstays so you really need to explain how it's relevant. – Móż Jun 16 '16 at 1:42
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    OK, Móż, I edited it. You scroll down to symmetry at the Sheldon link to find string testing. Doing that checks alignment. If it's off, then decide. – user26530 Jun 16 '16 at 12:03

Are you referring to the way the seat stays bow inwards asymmetrically when looking at the bike from the back? If so, it's intentional and part of how Cannondale implements shock absorption on their road bikes. The seat stays flex to absorb shocks and are not symmetrical because of the space taken up by the cassette on the drive side.

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