Robin Hood

Hi all, I bought an old Triumph hybrid with a traditional 3-speed Sturmey Archer set-up which worked perfectly until I moved the switch about 3" along the curvey swept-back handlebars so I could actually reach it without taking my hand away from the handle! I was surprised to find this resulted in 1st gear switching itself into 2nd a few seconds after setting off, and indeed any time I switched down to 1st. I put up with this for several days, partially because I rather liked the 'automatic gear' feature that I had produced However I've now read that it's not a good idea to run it like this, so I'm expecting to only have to do some sort of fine tuning on it. I've returned the switch so it's out of reach again, which has returned it to GWO. Is this a known problem with hub gears?

Andrew R Stewart 

No. Unless the cable/casing lengths are so short that by moving the trigger unit you also have tugged on the cable. What is possible is that the new location for the trigger resulted in distorting the trigger's internals, affecting it's movement.


Do you know how to preform a cable/indicator chain gear adjustment? It might just be that the current adjustment is really close to one end of the acceptable end.


I would also lube the hub (only a teaspoon's worth of medium oil, NOT chain lube) and trigger unit. Andy.

Robin Hood

Hi Andrew, thanks for the informed reply. Is a cable/indicator chain gear adjustment the one where you put it in 2nd gear then rotate the adjuster, and can you tell (by my description) which way it should be turned ? I expect you need to know how much linkage is showing when in 2nd gear, so would a pic tomorrow help? (it's dark here now). 'Medium oil' isn't a term I'm familiar with but I expect a compatriot will be along soon to advise me!

dweenk

Try this link. It may clarify the adjustment procedure.
Sturmey-Archer Internal-Gear Hubs, Tech Tips

Andrew R Stewart 

Medium oil as in not thin TriFlowish stuff or thick grease. Think of 20/30 weight auto grades. Years ago I got a quart of 20w machine oil, no additives no weight range. This is what I used for IGhs for a couple of decades (and on my lathe).


But as I've said here before, it's more about using some kind of lube then the specific form. Like bathing, that you use some soap counts, not whether the soap is Dr Broners, Lava or dish soap.


I've seen far more IGH damage from a lack of lube then the wrong form.


As to the gear/cable adjustment- yes. But using the indicator chain position only works if the IC is the 'right" one for the hub/axle. Since ICs are so easily damaged they get replaced and often with just what's on hand. So while I start the adjustment by looking for the IC's shoulder lining up with the axle's end (when in 2nd gear) I find I need to use the alternative method often enough. Trigger in 2nd, watch the cog/spokes relative rotational paces. In 2nd they should rotate together (at least with the SA AW and similar IGHs, they are direct drive in 2nd). "Tighten" up the cable adjuster till 1st gear is just starting to engage (the spokes rotate slower then the cog as in reduction). Mark this spot with the adjuster's lock ring. Loosen the adjuster till 3rd gear starts, the spokes are rotating faster then the cog. You will see the amount of adjuster threading that is 2nd gear's range. Tighten the adjuster to half this and secure with the lock ring. Confirm with a test ride. Andy.