Originally Posted by
Chesterton
There is a "neutral" space between second and third where nothing is engaged, so it might be that you think you're in first but actually in second, and then hitting the neutral when you think you are going to second.
That's it. I actually can't get first to engage at all.
Originally Posted by
Andrew R Stewart
If the cable is detached from the indicator chain and then the indicator is pulled by your fingers while pedaling what happens? If all works well (you can see the spokes running "behind" in 1st gear, stay even with the cog in 2nd and "advance" forward of the cog's rotation speed in 3rd) then the problem is likely cable.
Didn't occur to me that to check what gear I was in this way. Turns out I was in second in both scenarios, and first doesn't work at all. Looks like its time to open the hub up!
Thanks everyone!