Bicycle Mechanics - Sliding Droputs on Track-Ends

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View Full Version : Sliding Droputs on Track-Ends


tswg
07-23-09, 03:10 PM
Can it be done? It looks like the sliders could be connected to the track-end dropouts, but I've never held the two of them at the same time to compare. I've been contemplating converting a track-end bike to handle disc brakes, and adding sliding dropouts is one way I've come up with.

The only real issue I foresee is that you would reduce your rear spacing from 135 mm to maybe 130 mm.

I'm assuming it can't be done cause I can't find anyone that's done it, but I thought I throw it out there for comment.

mikE


jimn
07-23-09, 04:54 PM
Daft idea, but might work anyway.

Disk brakes put a lot more force, and of a different kind than intended, on the stays of your bike. The other thing is, you'd be lifting the rear end of the bike a bit, changing the seat tube and head tube angle, and the bb height. You COULD lift up the front a bit to compensate.

tswg
07-23-09, 05:03 PM
Good point on the forces. Without a perfect (designed) fit, they'd probably rip out of the stays at some point.


tatfiend
07-23-09, 10:03 PM
If you look at normal dropout width you would reduce rear spacing to more like 123mm or narrower as standard dropout widths are normally in the 6 to 10mm range from my observation. Need precision machining too in order to keep the bolt on parts from slightly shifting vertically in the original track dropout slots, causing the rear wheel to get out of alignment vertically.

Sliding dropouts seem to be increasing in popularity as they are used on the Civia Hyland and a couple of new Swobo models that I am aware of, and presumably other bikes too. I have the Civia and the disc caliper mounts to one sliding dropout so that the caliper and disc maintain the same positions in relation to one another when the chain tension is adjusted. The frame though is specifically designed for the sliding dropouts with the adjustment bolts well separated and the frame has slots to accomodate the sliding dropouts and prevent any vertical alignment shifting.

The Civia and one of the Swobos is IGH while the other Swobo is SS/FG using the new locking/unlocking SRAM single speed hub. This hub allows operation in either FG or SS modes.

jimn
07-24-09, 07:58 AM
Huge tangent:

Are sliding dropouts an overengineered solution to a problem horizontal dropouts already fixed?

tswg
07-24-09, 08:28 AM
jimn - Not if your are running disk brakes. They would make my life a lot easier if I had them on my Pugsley. I have two wheelsets (29er and 26x4) and everytime I swap sets I end up having to re-adjust the brakes.