After another evening of work on
Mauricio's 1969 Huffy/Raleigh Sportsman, I took the grip shifter home to try to figure it out. Turns out, it's pretty simple on the inside, but since I couldn't find any how-to guides on the interwebs about it, I thought I'd post one.
The whole works is basically held together by a little spring clip that fits just under the lip of the dial portion of the grip. I used a small screwdriver to pry the clip out of its channel. In the photo below, you see the clip after removal.
With that done, the housing for the shifter (at left above) just comes off (assuming you've already removed the screw that tightens the shifter to the handlebar), exposing the minimal inner workings of the mechanism. There are basically three parts: a small spring, a bearing, and the rotating mechanism to which the cable is attached. The spring sits in a little hole, and the bearing on top of the spring. When the grip is turned, the bearing slides into one of three holes in the rotating mechanism, either tightening or loosening the shifter cable, and thus shifting the hub.
In the photo above, you can see the rotating mechanism at right with the red indicator arrow on it. Below, you can see the spring in its hole, with the bearing resting on top.
That's about it. I haven't put the thing back together yet, but I'm guessing that making sure the cable and bearing stay in place while the spring clip is reattached is going to require at least one more hand than I currently have. I'll have to look into getting another one.
There's a fuzzy diagram
here of the whole works, and if you combine it with the photos above, you can get a pretty good idea of how it all works. Apparently, though, this was not a very successful design and seems to have only been on 1960s bikes.
Ah, the wonders of the interwebs and the machinations of fate. Mauricio happened to take a wrong turn the other day, and when he stopped to ask directions, noticed the white tail of this Raleigh-made Huffy Sportsman peeking out of a garage. He asked if the bike was for sale, and lo and behold, took this lovely specimen home for a mere $10. Pretty good haul for getting lost.
So then, whilst Googling "Huffy Sportsman" he found my blog, and (this is the best part) discovered that we live only about twenty minutes away from each other. Long story short, that's Yours Truly in some of the photos below.
I went over to Mauricio's last night and we got started taking things apart. This is Mauricio's first old bike project, and it's perfect for learning. The cables are all broken, the rust is pervasive, but not impossible, and much of the chrome appears to be nearly pristine under the thickest coat of road/storage grime I've ever seen. It took a fair amount of work to even find the date stamp on the hub. The really cool thing is that this bike is equipped with a Sturmey-Archer grip-shifter, which I've never worked on before, so I get to learn something new.
More photos to come as Mauricio and I get our hands dirty and get his bike ready to roll again.
Images: Except for the one at top, all photos by Mauricio.
