4

I have a second hand chapelli 3 speed bike.

Everything was fine until I got a flat tire on my back wheel.

I was able to figure out how to get the back wheel off (after a bit of Googling), by disconnecting the back shifter and thus allowing the wheel to come off.

After putting the tire back on, I realised I had moved the lock nut for the adjuster and couldn't remember quite where the shifter adjuster was previously set to. I put it back to where I thought it went and took it for a test ride and it was fine.

Recently, I have noticed that sometimes the gear slips a little (I think that's the right word for it) when I am riding and I change gear; I will be pedaling and it feels like it "slips" as the pedals will drop a little as if missing something and then pick back up normally.

I found a manual for my shifter online today, and the diagram has suggested the below is where I should adjust my shifter to:

Bike diagram

I'm not a huge bike person and less so a mechanic and so had a little trouble following the instructions for "Gear Adjustment" on the manual I linked above. Based on the diagram, I got my shifter adjusted to the below:

Shifter as per my adjustment

Have I interpreted these instructions correctly?

  • I've only once touched a bike with a 3 speed Nexus IGH, and it was straight forward to not touch the gear control system other than simply disconnecting it. Looks like yours pulls the shaft out to change gear, mine pushed the shaft in to change gear, so completely different. – Criggie May 20 '17 at 10:11
  • 2
    Yeah, his is a Sturmey Archer hub, from the looks of it, a SRC-3 if it's a coaster brake... – CardMechanic May 23 '17 at 20:02
  • pictures to make things clearer would help. – user45994 Nov 2 '19 at 22:15
4

I actually use that hub quite a bit, and was just looking into that setting for one of my customers earlier. The "set" gear is 2. set the shifter in 2, then yes, you want the connection from the chain to pin to be just protruding from the axle. Once you set it like that once, lift the back wheel off the ground and pedal it one revolution forward and pedal it backwards to engage the brake once just to be sure it's engaged in the gear, and check it again. If it has "settled into gear" and the position of that pin has changed, set it again.

Once you get it so in gear 2 the pin has stayed at that point, you should be good. Check that all gears are working, and that it isn't slipping like you said in your original post. Riding it for long periods of time with it slipping out of gear will wear out the internals very quickly.

| improve this answer | |
3

Sturmey Archer hubs are finicky to say the least but once you become familiar with how to do it, they'll never bother again and they can last forever. I relied on Sheldon Brown's guide http://www.sheldonbrown.com/sturmey-archer/adj.html as a base of concept. The steps I follow are:

  • Connect the gear spindle into the hub all the way until stops. Then go back a third of a turn.
  • Connect the gear cable to the spindle. Go down to about 2/3 of the thread. Move the lock ring all the way down.

Default gear is HIGH (3). this mean there is no tension in the cable and the spindle is all the way into the hub. And Low gear (1) is when the cable is at the tightest. So you want to set the low gear first

  • Set the gear shifter to Low (1)
  • Pull -don't disconnect- the spindle as far out as you can and Hold it
  • Tighten the gear cable until the spindle cannot go back into the hub. The gear cable should be tight.
  • Shift to High (3). The cable should be slack.
  • Shift through the gears and make sure it click as it stops in each gear. If it stops in (2) but not in (1), loosen the cable by 1/3 of a turn.

(1) and (3) gear are sort easy to set (tightest -- loosest tension) (2) is the tricky gear to set up. So ride the bike down the street and shift between gears. Keep going for a few pedals revolutions. If the gears are aligned very close, it will take a few revolutions for it to skip. When it does, play around with the gear cable accordingly. Repeat these steps as necessary:

  • Shift between gears (1) and (2): If (2) doesn't engage: Loosen up the cable by 1/3 of a turn until it does.
  • Shift between gears (3) and (2): If (2) doesn't engage: Tighten the cable by 1/3 of a turn until it does.

Once you feel the gears are aligned, bring the lock ring up to lock the gear cable.

As the gear cable stretches, the gears will get out of synch. You will notice that because gears will start skipping. Just tighten to gear cable by 1/3 or a turn.

It will take time to get it right and it can be frustrated. If no matter what you do, the gears keep skipping, don't ride the bike as you will damage the internal mechs of the hub. I learn that the hard way. Instead, bring it to the bike shop and have then set it. Then asked them to show you what they did.

| improve this answer | |
  • Do you know if this method works for a 5 speed SA shifter as well, obviously substituting 3 for 5 where applicable? – Kibbee May 23 '17 at 20:13
  • @Kibbee, No Unfortunately i don't. – Baratier ErebusDuHalm May 25 '17 at 4:10
0

The Sturmey Archer twistgrip type gear shifter seems to me to include an automatic self-adjust feature which acts to tighten the cable when there is too much slack in it. If this is not the case (and, indeed, I can't find it mentioned anywhere) then this effect must be accidental. Either way, beware of moving the gear shifter with the cable disconnected or any slacker than necessary, otherwise the cable will become too short (and the coloured gear indicator flag with move down around the shifter and might disappear completely). To correct a cable that has become much too short for this reason, avoid taking the shifter completely apart because small parts are likely to get lost. Instead, loosen the two screws holding it together, then try to move the metal spring strip (with the window for the coloured gear indicator flag) clockwise as viewed from the end of the handlebar, then re-tighten the screws. Pulling on the gear cable also helps with this.

| improve this answer | |

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.