Tuesday, October 18, 2011

One by Nine

This is just a short blurb to show my handy work from the summer when I converted my bike to a 1 x 9 setup. I had been thinking about it for a while and I had a worn out drive train and XT chainrings are expensive so it was the perfect opportunity.

The setup is based on an e-13 / mrp BB mount type with a guide like I saw on the Specialized website. It has a plate that clamps between the out board bearing cup of the bottom bracket and the bottom bracket shell of the frame. It allows for vertical adjustment of the actual guide to accommodate different size chainrings and a couple spacers to allow for different offsets of the chain line depending on the model of ring. Right now I am using either a 32 or 34 tooth Salsa ring for MTB and a 36 tooth Black Spire for 'cross. The whole thing weighs around 45 gms and allowed me to drop at least a pound of derailleur, shifter, and cable off my bike and I swear it is slightly noticeable.

It functions like a dream and I have never dropped my chain once so this would now definitely be my preferred setup. It cleans up the bar and simplifies shifting while still providing all the gearing range I need for 99% of my riding.

I made the whole thing with only a hack saw, drill, files, and a router. Not bad I dare say. I like to imagine what I could do with a milling machine. Actually I suppose I did use my lathe to get the spacers to an accurate size. Anyway there is not much I could think of changing other than to make it prettier and shorten the screws so they don't stick out the back so far.

The pictures below were taken at the end of my last bike race so there is a little mud but not too bad. The photos themselves are horrendously out of focus so I evidently need to learn how to manually focus my compact camera. The ground is in lovely sharp focus but the actual subject matter is at least 6 beers blurry. This was not identifiable on the camera's screen so I didn't realize when I took the shot. I will try to take another that looks better later.

One interesting thing to note about this setup is that now when I am on my road bike, I always forget to use my front shifter and regularly find myself cross chained from rings to cassette. This is of course not ideal but I imagine it is just an adjustment to ride two different ways.