Right hand shifter not shifting

[Kell]

I have a 2015 6-speed Brompton.

Last week, I was struggling to get it to shift to the higher gears (5/6) as the shifter felt like it was stuck on something. Would go after several attempts, but sometimes I needed to flick it the other way first and then it went.

Unfortunately, I was away all last weekend and will be away all this weekend, so time is limited.

But I do need to give it a look at as there were several times this morning when I couldn't get it to shift at all. Given that 4th and 5th are my two most used gears, it's problematic.

In order to save time diagnosing, does anyone have any idea what could be causing this? i.e. which end should I start looking at? D Othey shifters wear out? Is the chain at the other end end likely to catching on something?

TIA

 

[T4tomo]

disconnect cable and see if derailleur & shifter both move freely by hand

if they are both fine then renew your cable inner and outer.

if they aren't fine then your into blasting with GT85 and praying!

 

[T4tomo]

oh hang on this a brompton innit.
could still be a sticky cable issue
SA or SRAM hub?

 

[Kell]

It's the BWR hub so SA I think.

 

[Kell]

SO I had a look last night and I think the shifter's knackered.

The little nut at the back has somehow shaken loose (and fallen out) so it's not all sitting together properly and holding everything together properly. by holding it all together with my hand, I can get it to shift so I could just try and source another nut, but I've gone ahead and ordered another shifter.

Though I did think after that, should I have used it as a change to upgrade the shifters? Do the new one work with the old gears?

 

[cyberknight]

is this the right part ? might be worth contacting brompton direct
https://www.brompton.com/p/1073/brompton-hub-gear-right-hand-shifter-pre17

 

[Kell]

Yeah - it's the rabbit ear shifter.

It's literally just the nut on the back (you can't see it in the links) but it fits into a recessed hexagonal hole on the reverse and the M3 (maybe) hex bolt screws into it.

On a related note, it annoys me that the right hand and left hand shifters use different allen key sizes.

 

[Kell]

Further update.

The new shifter arrived, but I've not replaced them before and in order to switch the shifters the whole cable has to be removed. As it turned out my gear cable was completely shagged. I had to use pliers to get it out, so there's no way it was going to go back in.

So I needed to order another one which hasn't arrived yet. So still not fixed.

 

[Ming the Merciless]

So I needed to order another one which hasn't arrived yet. So still not fixed.

Gear cables are standard common items. You can get a new cable in the time it takes you to get to your LBS and back.

 

[Kell]

Gear cables are standard common items. You can get a new cable in the time it takes you to get to your LBS and back.

The nipple doesn't look standard - pretty sure they're not interchangeable with any old gear cable.

 

[T4tomo]

could still be a sticky cable issue

The nipple doesn't look standard - pretty sure they're not interchangeable with any old gear cable.

Yes best to get proper brompton one. You also need the correct cable length for your handlebar type so it still folds properly.

 

[Kell]

All fixed.

Shifter was definitely to blame for probably 99% of the issue. Pretty sure the cable didn't help though. I don't remember it ever shifting this well.