# A New (To Me) CAAD5



## SRV (Dec 26, 2006)

I just bought my first Cannondale with the idea of racing a few crits this year. I got the bike for a good price, but there are some things I want to change and need some help in determining sizes.

The bike currently has a 9 speed triple 105 Octalink crank and bottom bracket. I want to change to a double and possibly upgrade while I'm at it. My problem - I don't know what size BB or derailleur clamp size to look for. Any problem using a newer 10 speed crank with the other 9 speed components?

The other item is the seatpost which is a Ritchey Comp that looks like it weighs 5 pounds. What seat post diameter for a replacement?

Thanks for the help.


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## MaestroXC (Sep 15, 2005)

SRV said:


> I just bought my first Cannondale with the idea of racing a few crits this year. I got the bike for a good price, but there are some things I want to change and need some help in determining sizes.
> 
> The bike currently has a 9 speed triple 105 Octalink crank and bottom bracket. I want to change to a double and possibly upgrade while I'm at it. My problem - I don't know what size BB or derailleur clamp size to look for. Any problem using a newer 10 speed crank with the other 9 speed components?
> 
> ...


1. There shouldn't be any problems using a 10v crank with 9v chain/cassette/shifters. You may want to use a 10v chain just in case.

2. Cannondales are English threaded; ie 68mm shell. BB spindle length depends on the crank, and in your case, 105 Octalink BBs are different from Ultegra and Dura Ace BBs; the spline on the 105 spindle is longer. For instance, if you get a 105 Octalink double, the spindle length will be 112 or thereabouts, and Ultegra or DA will be 109.5. Don't worry overmuch, just ask the shop or site you buy from about compatibility and they should be able to steer you right. You can find 9v Dura Ace doubles in good shape on eBay fairly frequently, such as these, or these Ultegras.

3. Derailleur clamp on a CAAD5 should be 31.8
4. Seatpost diameter is 27.2.


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## SRV (Dec 26, 2006)

Thanks for the info, Maestro. That's exactly what I needed.


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