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kaniamazdar
Showing posts with label 1971 Columbia Sports III (AFTER). Show all posts
Showing posts with label 1971 Columbia Sports III (AFTER). Show all posts
Saturday, 9 August 2008
Sunday, 3 August 2008
Friday, 18 July 2008
How to Adjust a Sturmey-Archer Three-Speed Hub
Sometimes I actually post useful information. Sometimes.
So, I've kept kind of quiet about it, but ever since I put my Columbia Sports III back together last, uh, November, I've been having trouble getting the hub adjustment right. This is mostly the result of the fact that I experience problems while on a ride, stop to quickly make some stop-gap adjustments, then realizing later that it's still messed up, and just keep repeating the process. Finally, I got fed up with it, and decided to devote some time to getting everything adjusted exactly right.
As usual, Sheldon Brown has the definitive guidance on the subject, but I wanted to make things a bit more explicit and illustrated for you fellow first-timers. So, here we go:
Correct hub adjustment is extremely important. First, it allows you to take full advantage of all three of your gears. Second, it prevents "freewheeling," which isn't nearly as much fun as it sounds. Freewheeling on a 3-speed occurs when the internal gizmos in the hub align so that the pedals can spin forward without engaging the drive. In other words, the pedals are turning, but you're not moving the bike forward anymore. This can be extremely dangerous when you think you're solidly in a gear and pedaling along with resistance and suddenly your legs start spinning uncontrollably. This throws your whole bike/body alignment out of whack and you are certain to at least wobble, and possibly lose total control. Not good for riding in traffic or crossing an intersection, certainly.
Proper adjustment is actually pretty easy, provided you have an ample dose of patience. There are basically only two parts to adjust: the indicator spindle, and the cable tensioner. The indicator spindle is the little rod and chain that emerges from the right side of the three-speed hub. One end of the rod is threaded with tiny threads, and this end screws into the hub itself (see photo). This is where you make your first adjustment.
Disengage the shifter cable from the indicator spindle so that you can unscrew the indicator spindle and take it all the way out of the hub. Check to make sure it's not bent or damaged. If everything is okay, reinsert the indicator spindle and tighten with just your fingers until it stops, then back it off a half turn. This is really important, because if you back it off too much, the indicator spindle doesn't fully engage with the gearing mechanism inside the hub. This was my problem, and caused me no little amount of frustration before I realized it. If the indicator spindle isn't seated properly in the hub, no amount of adjustment to the cable will help.
Now, reattach the cable to the indicator spindle. Tighten the cable tensioner (the barrel on the end of your shifter cable) by screwing it on to the indictor spindle, and use the little locknut on the indicator spindle to hold the tensioner in place. It should look something like this:
Now comes the tricky part. I'll let Sheldon Brown explain it, with particularly important passages highlighted:
For best results, adjust the cable by tension. When the trigger is in high gear position, the cable should be totally slack. Shift down to middle gear, while watching the indicator chain-it should clearly move as you make the shift. Then shift to low gear; again, you should see more chain coming out of the end of the axle. Sometimes the internal parts line up in such a way as to prevent downshifting. If you have trouble getting the hub to downshift, turn the pedals slightly forwards. Once you are sure you are in low gear, take hold of the indicator spindle chain and try to pull more of it out of the axle. If the adjustment is correct, you should be able to get just a tiny bit more movement from the chain. If it is completely taut, the cable is too tight. Make sure to tighten the knurled locknut on the indicator spindle so that the adjustment will stay as you have set it.
Double check the adjustment in all gears. In low gear, you should be able to see that the sprocket moves faster than the wheel, and the hub should not make a ticking sound while being pedaled forward. In middle gear, the sprocket should move at the same speed as the wheel, and you may hear a slow ticking as you pedal. In high gear, the wheel should turn faster than the sprocket. The same slow ticking may be audible in high gear.
If you hold the trigger halfway between middle and high gear, the hub should disengage so that you can spin the pedals forward without going anywhere. If it freewheels forward in high gear, the cable is to tight or has too much friction to release properly. If it freewheels forward in middle gear, the cable is too loose.
If you're anything like me, you will have to make many minute adjustments to the cable tension until you get it just right. The key points again: 1) properly seat indicator spindle in hub; 2) freewheel in high gear means cable is too tight; 3) freewheel in middle gear or low gear means cable is too loose; 4) there should be no ticking sound when pedaled forward in low gear; 5) hub should freewheel between 2nd and 3rd gear.
If you would like to read Sheldon Brown's original article in its entirely, go here. Sheldon also has lots of other great information about three speed (a.k.a. planetary, or epicyclic) gearing, including diagrams that show what's going on in there.
By the way, my experience related here is based on the Sturmey-Archer AW hub that is original to my Columbia, I have no experience with other S-A models or other hub-geared systems.
Sunday, 18 November 2007
Friday, 16 November 2007
IT LIVES! Mwaaa-ha-ha!
Two big revelations today: 1) I actually have a bike with three speeds now, instead of a three-speed bike that doesn't work right; and 2) I am dramatically out of shape.
Both of these came to me today while taking my bike for its first test ride. Let's focus on the first one. After much adjusting and fidgeting and swearing, I finally got the shifter cable adjusted properly (see Sheldon Brown's how-to section on 3-speed cable adjustment--it's about half-way down on the linked page.) The real bugger was getting it adjusted so that it wouldn't freewheel in the middle gear. I now thoroughly understand how to make such adjustments in the future. Thoroughly.
For the first year that I had the bike, I never noticed much difference in the three gears, and now I know that I probably wasn't even moving through the gears when I moved the trigger. Having all new parts (cable, trigger shifter, and indicator spindle) makes a huge difference, and knowing how they should be properly adjusted is essential. It's really a joy to ride now, especially with everything greased and oiled. I was hoping to notice a dramatic difference in the way it rode, but I had no idea it would be this dramatic! I wish I had done this as soon as I got it.
I've got a few more little adjustments to make on the brakes and a loose nut to tighten on the rear fender, then I'll polish it up with another coat of Turtle Wax and take some "after" pictures. I've also assembled an album of "before" pictures that didn't get posted. An "after" album will go up soon as well.
PS--check out my Google map to the right for the route of my test ride today.
Both of these came to me today while taking my bike for its first test ride. Let's focus on the first one. After much adjusting and fidgeting and swearing, I finally got the shifter cable adjusted properly (see Sheldon Brown's how-to section on 3-speed cable adjustment--it's about half-way down on the linked page.) The real bugger was getting it adjusted so that it wouldn't freewheel in the middle gear. I now thoroughly understand how to make such adjustments in the future. Thoroughly.
For the first year that I had the bike, I never noticed much difference in the three gears, and now I know that I probably wasn't even moving through the gears when I moved the trigger. Having all new parts (cable, trigger shifter, and indicator spindle) makes a huge difference, and knowing how they should be properly adjusted is essential. It's really a joy to ride now, especially with everything greased and oiled. I was hoping to notice a dramatic difference in the way it rode, but I had no idea it would be this dramatic! I wish I had done this as soon as I got it.
I've got a few more little adjustments to make on the brakes and a loose nut to tighten on the rear fender, then I'll polish it up with another coat of Turtle Wax and take some "after" pictures. I've also assembled an album of "before" pictures that didn't get posted. An "after" album will go up soon as well.
PS--check out my Google map to the right for the route of my test ride today.
Tuesday, 13 November 2007
Arr, she's a fine lookin' craft, but will she sail?
That, more or less, is the question. I put the fenders and wheels on today and it was nice to see my bike looking like a bike again, instead of just a collection of parts. I have to admit, I was a little surprised at how good it looks. Damn good, if I may. If it rides half as good as it looks, I'll be happy.
I was a little afraid that when I put it back together, it would come out as something else entirely, like when the Simpsons tried to build a pool and built a barn instead. Then, the Amish guy says, "'Tis a fine barn, but sure 'tis no pool, English." Yeah, that's what I thought would happen.
Next, I'll put on the chain, the brake and shifter cables, the brake shoes, and chain guard. Then, make some adjustments and tighten everything down and I'll be done. I'm a little nervous about cutting and installing the cables, since it's pretty important and I've never done it before. 'Course, I guess I've never done any of this before...
Sorry about the poor lighting--I'm saving the really nice pics for when the whole thing is done.
I was a little afraid that when I put it back together, it would come out as something else entirely, like when the Simpsons tried to build a pool and built a barn instead. Then, the Amish guy says, "'Tis a fine barn, but sure 'tis no pool, English." Yeah, that's what I thought would happen.
Next, I'll put on the chain, the brake and shifter cables, the brake shoes, and chain guard. Then, make some adjustments and tighten everything down and I'll be done. I'm a little nervous about cutting and installing the cables, since it's pretty important and I've never done it before. 'Course, I guess I've never done any of this before...
Sorry about the poor lighting--I'm saving the really nice pics for when the whole thing is done.Monday, 12 November 2007
Surprise! Reassembly!
I had planned on doing the second clear coat today, and even started on it, but the first piece I coated (the front fender) got all bubbly and cracked and spotty-looking. I think I must have put on a too-heavy coat, but I decided not to push my luck with the other parts. So, instead of doing two coats of clear coat on everything, I'm calling it good with just one. Tomorrow, I'll buff off the botched clear coat on the front fender and then try to reapply it more smoothly. I put a coat of Turtle Wax on everything else, which will also act a protecting layer. Then, I took off the masking tape from the bearing cups and head badge and started putting the whole thing back together. As you can see below, I got the fork and handlebars, the seat, and the crank put back on the frame.
Nothing too technical here. I just put the seat back on so I could flip the bike over later to work on the crank, fenders, chain, etc.
Here's how I put the fork and stem on: 1) pack the bottom bearings of the fork and set on the bottom bearing race; 2) insert the fork into the tube and let the frame rest on the fork; 3) grease the bolt and expansion wedge on the stem and pack the top headset bearings; 4) insert the stem into the tube and tighten the stem bolt.
Tips on the process: 1) don't tighten the bearing races too much, just enough to hold the bearings in the cups. If you tighten the races too hard, they won't turn freely; 2) same goes for the stem bolt; it should be tight, but not so tight that it affects the steering of the bike; 3) try to line up the fork and handlebars with each other and with the frame; you can fine-tune once the bike is ridable, but the straighter everything is now, the easier it will be to make fine adjustments later.
And then, the crank. Pretty straight-forward: pack the bearings and grease the cups, lightly tighten the bearing race on the left (non-chain) side, and put the hardware back on. Again, when you tighten the nut on the outside of the left side, don't make it too tight, as this will push the bearing race into the bearings and affect the turning of the crank. Remember, the nuts and the bearing race on the crank turn counter-clockwise so they won't spin off while you're riding, so they don't have to be made too tight.
So, there you go--clear as mud, right?
Nothing too technical here. I just put the seat back on so I could flip the bike over later to work on the crank, fenders, chain, etc.
Here's how I put the fork and stem on: 1) pack the bottom bearings of the fork and set on the bottom bearing race; 2) insert the fork into the tube and let the frame rest on the fork; 3) grease the bolt and expansion wedge on the stem and pack the top headset bearings; 4) insert the stem into the tube and tighten the stem bolt.Tips on the process: 1) don't tighten the bearing races too much, just enough to hold the bearings in the cups. If you tighten the races too hard, they won't turn freely; 2) same goes for the stem bolt; it should be tight, but not so tight that it affects the steering of the bike; 3) try to line up the fork and handlebars with each other and with the frame; you can fine-tune once the bike is ridable, but the straighter everything is now, the easier it will be to make fine adjustments later.
And then, the crank. Pretty straight-forward: pack the bearings and grease the cups, lightly tighten the bearing race on the left (non-chain) side, and put the hardware back on. Again, when you tighten the nut on the outside of the left side, don't make it too tight, as this will push the bearing race into the bearings and affect the turning of the crank. Remember, the nuts and the bearing race on the crank turn counter-clockwise so they won't spin off while you're riding, so they don't have to be made too tight.So, there you go--clear as mud, right?
