Once the cable is out (feel free to cut it if the cable doesn't slide out), remove the tension pulley using either a 9mm wrench or socket:
Now slide the chain off the remaining pulley and loosen the bolt on the derailleur's claw which holds it onto the bike's frame (if you have a chain tool, it may be easier to just break the chain rather than remove the tension pulley right away). The derailleur should now slide off the frame, and you can begin cleaning the parts:
The pulleys on these derailleurs are cool because they have little ball bearings in them. Unfortunately they tend to get gunked up and don't spin freely. They can be disassembled by putting two 13mm wrenches on the flat parts and unscrewing. Here's a closeup:
Taking the pulleys apart isn't necessary however, and the guide pulley (the one you didn't remove yet) doesn't come off without removing the rest of the derailleur cage. Instead I recommend just dripping some oil into the pulley bearings. The pulleys should spin easily afterwards. The rest of the derailleur can be completely disassembled, quite unlike modern derailleurs. The steel plates that move the cage back and forth are secured by nuts and bolts, unfortunately these tend to loosen up during use.
The barrel adjuster screw may seize in place on these derailleurs. If it is hard to turn, use pliers to unscrew it completely, then clean and grease the threads before reassembling. The spring can even be omitted if the adjuster is especially hard to turn. This screw is only used to take the slack out of the cable upon reassembly.
Here is the nearly finished derailleur in all its glory:
Make sure the pulley cage's spring is contacting the stop. If the cage just flops around, rotate it counterclockwise until the spring catches the stop. The derailleur is installed in reverse of its removal, by sliding the claw back into the frame dropout, removing the tension pulley, looping the chain around the guide pulley, then reinstalling the tension pulley with the chain in place. Again, you can also break the chain if you have the proper tool, and reconnect it once the derailleur is back in place.
Finally, thread a clean and oiled cable through the outer housing pieces and bolt it onto the derailleur. Check the limit screw adjustment with the back wheel on, and make any adjustments if necessary. The screw on the front of the derailleur is the high limit screw, and the long one on the bottom is the low limit.
With the derailleur reinstalled, it's a good idea to clean the plates that move the pulleys back and forth. I like to shift the chain into the biggest gear and use a
flat screwdriver to scrape the caked on grime from the derailleur's
moving parts. Lubricate each pivot point with oil or WD-40 so that the
mechanism can move freely:
excellent info - been hunting online for weeks on and off for info on rebuilding the derailleurs on both my 72 Collegiate and 69 Stingray, THANKS.
ReplyDeleteAny info on the overload tube thingy on the Stingray ?
The overload tube just looks like a very long cable ferrule that connects the cable housing to the shifter. I've also seen pictures of Stingrays without the tube, and with just a standard cable connected to the shifter, so the tube may not be totally necessary. I haven't actually worked on a Stingray though, so I could be completely wrong :)
ReplyDeleteThanks for this excellent advice. I just set up the Allvit on my Mk1 Raleigh Chopper 5 speed and this was invaluable. Best wishes.
ReplyDeleteExcellent write-up, thanks! What type of oil do you recommend for the cables?
ReplyDeleteI usually use plain old motor oil and that works fine for several years. WD-40 dries up and needs to be reapplied often so I don't recommend it because of that. I think Triflow is the best for clean cables, but I don't know how it works long term. Cables usually aren't too picky though, so as long as you're using some kind of oil then you'll be ok. It's much more important that the inner cable and the housing pieces aren't caked in dirt or rust.
DeleteI have a Huret and I was wondering what size ball bearings to use? I ordered 1/8ths and they don't seem to fit.
ReplyDeleteI remember they are super tiny, but unfortunately I never measured them. If you still have the original ball bearings then you should just reuse them. If not, I would guess they are 3/32".
DeleteDo you know how many bearings go in each pully? I just took one apart and lost a bunch not knowing that they were even in there.
DeleteI'd guess about 15. I don't even take those apart anymore, I just add motor oil to the bearings from the outside and that works fine (I guess I'm lazy now).
DeleteI just picked up an old Varsity with a Schwinn derailer. The pulleys seem to have no teeth and appear that they never did. Been a long time since I worked on an older bike. Any thoughts.
ReplyDeleteYou're right, those derailleur pulleys never had teeth on them. I ran across one like that and the shifting wasn't so great. Maybe yours will work better than mine did though.
DeleteHere is the challenge. They are not in so good of shape. I wonder if I can get parts or need to get a new derailleur
DeleteActual Schwinn replacement pulleys would be pretty hard to come by, but I imagine that you can use pulleys from almost any old derailleur. If you're going to ride this bike a lot I'd probably look for an old Shimano Skylark/Eagle or Suntour Seven/Hero derailleur because they're dirt cheap and work a lot better than what you already have.
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