RX100 shifters woes - any advice?

[Ugo51]

hello lovely people,

I just got myself a nice Orbit Harrier, which came yesterday (eBay purchase). It has RX100 groupset (3x7), calipers, derailleurs, shifters, the whole thing. It's very beautiful.
Only drawback...it's broken.
Honestly...very disappointing, especially as I messaged the seller and he said he was aware of the left shifter not working, but he did "some work on it and managed to make it shift OK". Sadly, untrue.
The mechanism doesn't engage and while it's possible to shift up, it's not possible to shift down.
He offered a partial refund, but I am not even sure what to ask the refund for. The shifter? It's nigh impossible to find a RX100 triple. And if I change the shifters to another model, I will also have to change derailleurs and even the wheels, because I can't fit 8 speed cassettes (and up) on 7-speed hub.
Of course I can't ask for that. It would far exceed what I paid for the bike which, at £170 was quite good value.
Now, short of finding a RX100 shifter replacement, what other solutions are there?
- change everything "en bloc" and convert the bike to a 3x8 Claris or 3x9 Sora (I might be able to keep the rear derailleur, as I know it works with 8-speed shifters)
- convert to downtube shifters
- make a hotchpotch of parts and have mismatched shifters...? My heart quivers at such idea, but it is a possibility, I guess
- send the bike back (I'd really rather not do that...)

Any ideas?

Thank you!!

 

[pigman]

1. you can still fit a '8 speed' cassette on your wheels - but only use 7 of them. So, 7 cogs with 8 speed spacing.
2. shimano rear derailleurs were interchangeable. So, in theory you could use anything from the 5 - 10 speed eras and the indexing will work. As you work up to 9 and 10 speeds though the jockey wheel clearance is tighter, so use wider bolts and jockey wheels or a narrower chain. I'm not sure about front mechs, as dedicated series had different indexing
3. remove all the left hand gear stuff to leave a brake lever and make it a 1 x 7 setup

 

[Ugo51]

1. Are you sure? I have never handled a 7 speed cassette, but I thought a 4.5mm spacer was needed to fit one on a 8- speed hub, which suggests a 8-speed cassette won't fit on a 7-speed hub

2. yes, rear derailleur would be the only salvageable part from the lot if I decide to upgrade to more modern group set

3. I could. But it's VERY limiting for gearing options, and on a light-touring/commuting bike would be a shame to only have 7 speeds

 

[pigman]

1. Are you sure? I have never handled a 7 speed cassette, but I thought a 4.5mm spacer was needed to fit one on a 8- speed hub, which suggests a 8-speed cassette won't fit on a 7-speed hub

Yes, you might have to pack it out with a washer. But the spline arrangement will fit. Spacers are minimal cost. I was trying to suggest a quick n easy fix

 

[Ugo51]

Wait, maybe I am confused.
I thought a spacer is needed when fitting a 7-speed cassette onto a 8-speed hub

I have a 7-speed hub, onto which to fit (if possible) a 8- speed cassette

 

[jimo746]

Are we talking about the brake lever/shifter?
Have you tried liberally spraying the shifter mechanism with WD40 (best to use the straw on the can to get it right inside the mechanism), leaving it a while, and then repeatedly operating the shifters? Then repeating the process?
The old grease in the shifters can gum up the pawls on the mechanism, so either it won't engage when shifting up, or it won't release when shifting down.
You may need to give the gear cable a little pull when trying to shift down.
Also, poor cable condition of the inners/outers can cause drag and prevent the downshift, so worth checking that too . You could always remove the gear cable completely and see if the shifter will work normally.

 

[Ugo51]

Thanks. The previous owner must have tried that because the inside of the shifter (yes, it's an integrated brake/shifter lever) is squeaky clean.
With the inside mechanisms exposed (while braking) I can see that the pawl doesn't engage with the ratchet mechanism. To me, looks like the retention spring that holds the pawl down is tired, lost some tension, and doesn't keep the pawl in place

 

[jimo746]

I would still try what I suggested, it'll be worth spending a small amount of time seeing if you can "fix" the shifter for free, otherwise as you said finding a replacement could be time consuming & costly.
I suppose it's also possible the previous owner tried to fix the shifter, took it apart, and didn't re-assemble it correctly.
But if it was me, I'd be trying the "easy fix" with WD40 first...

 

[Ugo51]

Oh for sure I'll try. Just bracing myself for the worst case scenario....

 

[pigman]

Wait, maybe I am confused.
I thought a spacer is needed when fitting a 7-speed cassette onto a 8-speed hub

I have a 7-speed hub, onto which to fit (if possible) a 8- speed cassette

Ok, it seems I wasn't clear. Advance apologies if I now sound patronising (i'm trying not to be, but want to be clear).

Let's assume you currently have a 13-28 7 speed cassette and want to replicate this. Buy a 8 speed 12-28. Then discard the 12 sprocket and you now have 7 cogs 13-28 but with narrower spacing than what came with the bike. Mount this onto your existing wheels and it should fit ..... except your new narrower 7 speed is thinner than what originally was there, so you may need a spacer/washer behind the cassette to fill it. Fit the lockring and you're ready to go. When you then buy 8 speed levers, you will end up with an extra un-needed click, which you can ignore