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Daily Archives: January 17, 2014

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The Unbelievable Awesomeness of the Cannondale SR-400 Frame…

Cannondale - on the left, with my wife's Secteur (Right)

Cannondale – on the left, with my wife’s Secteur (Right)

Now before we even get into this, every single photo I’ve taken of my Cannondale, every one, was taken before I knew how to properly stage a bike…  I am well aware, and apologize profusely for being a noob and not knowing any better than having the drivetrain on the opposite side of the bike for a photo.  In fact, I’m planning a new photo session with the bike this summer so I can properly add it to my “My Bikes” page.

With that out of the way, I’m taking it into the shop today – I’ve finally found a use for those DT Swiss wheels that I broomed from the Venge because they were too heavy…

Now, this gets intricate so I’ll do my best to explain this well…  Anyone who knows anything about older frames knows that the rear dropouts are between 126.5 and 128 millimeters wide (for the noobs, the rear dropouts are the parts that hold the wheel in the frame).  This is a big problem when trying to upgrade an older aluminum frame because the newer wheels require a 130 mm dropout.  With a steel frame, you simply stretch open the dropouts and line them up so the wheel tracks straight.  An aluminum frame is different however, you can’t stretch them.  The aluminum is heat-treated so it’s very brittle – you run the risk of cracking the frame or one of the welds which could ultimately lead to a failure of the frame at speed and an accident.

The SR400’s Criterium frame is different though…  I read on a message board just the other day that stated modern wheels will fit, if snugly, into the dropouts as they are.  The SR400’s dropouts are set at 128.5 mm which means that they’re only 1.5 mm too narrow for a modern wheel.  What you end up with is a perfect, yet snug, fit of a modern wheel in an old frame, no stretching necessary.  The only trick will be getting the old cassette on the new wheel but we’re fairly confident that a spacer or two will do the trick.  One could make the leap that the snug fit will cause friction with the hub but I can assure you, it’s not anywhere near that snug – the skewer will cause more friction than the fit.

I also considered, for a minute, upgrading the shifters, chain rings, chain, derailleurs, cassette and going whole-hog with a modern 10-speed drivetrain but honestly, with the Venge and Trek in the stable, the decision came down to whether or not I needed to go to that length.  I don’t.  Either way I’ll be dropping at least two pounds on the Cannondale by switching the original wheels to the DT Swiss 4.0’s and gaining some fresh new wheels at almost no additional cost.

To round out this little project report, when I checked to make sure the new wheel would fit in the first place, I had to make sure that the wheel was sitting properly in the dropouts, that it wasn’t cocking to one side or the other (that the wheel tracked straight).  Unfortunately it didn’t, which I thought doomed this little idea before it even got started.  Just to make sure, I put the original wheel back on – and it was worse.  Who knew!  So there are a few ways around this without scrapping the bike.  I talked over three options with the Matt at the bike shop and settled on the last one…  It’s not off very much so we’re going to sand out some of one of the dropouts so the wheel sits in there straight.

Finally, I’ll wrap this little project up by giving her a new white saddle and I’m going to go with white bar tape to get it back to a more original look.  Photos to come once the snow melts.
UPDATE: She took a lot of work to get right… The dropouts were out alignment and way off center. Matt got it done though – two wheels from a 2013 race bike onto a 1990 Cannondale, with a 7 sp. cassette. Matt changed my mind on the saddle and bar tape too… Because it’s my nasty weather bike I’m going to go with black.

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