New gear cable fitted, gears change the opposite way??

[elduderino]

Forgive me if this has been covered before but...

I have Sora STI shifters on my touring bike and I've just fitted a new XT rear gear cable aswell as upgrading my rear derailleur from Alivio to Deore and now the gears change the opposite way to the previous set-up.

i.e. pressing the shifter inwards used to result in me changing up, now it changes down.

Anyone have any idea how this happened and how to get it back to normal.

Thanks

 

[andrew_s]

It's the new rear derailleur that's at fault.
MTB rear mechs come in two versions: "low-normal" and "top-normal", where top-normal is the same as road rear mechs and low-normal shifts the other way, requiring cable tension to shift to higher gears/smaller cogs. The traditional top-normal mechs have the cable clamp on the outer face of the parallogram, low-normal mechs have it on the inner face.
Low-normal is also called Rapid Rise. I think the idea was to stop the hard of thinking getting confused by pushing one lever for a higher gear with the left hand, and pushing the other lever to get a higher gear with the right hand.

All you can do is swap the rear mech for the correct version.

Correct version: http://www.chainreactioncycles.com/Models.aspx?ModelID=24088
Wrong version: http://www.chainreactioncycles.com/Models.aspx?ModelID=13775

 

[elduderino]

Thanks for that, sounds simple really.

I managed to track down the correct one for £17.60 new, slightly cheaper than crc £39.
The old one has now been put on Ebay.

 

[jpembroke]

Rapid rise alert! Happened to me once (LBS sold me one for my MTB by mistake) and I couldn't get on with it at all. Drove me nuts for a few weeks before I gave up and bought a 'proper' one.

 

[simon_adams_uk]

Whilst a rapid-rise/low-normal rear mech does mean that the gear shifters operate in the same 'direction' I don't believe that was the main reason behind creating them...

...when you're going uphill (and putting considerable loads on the drivetrain) it's much quicker/easier/better to shift into an easier gear with a low-normal setup. Only when you're accelerating do you have work against the rear mech spring which seems much more sensible.

I've used both and never struggled either way.

S

 

[zzpza]

yeah, i have no problems with the one i have on my mtb.

 

[jpembroke]

I can certainly see the logic in the theory but just couldn't get on with the reality. Also, I wondered how they function when the rear mech is covered in mud. Are they not prone to delays or non-shifts just when you need it most?

 

[zzpza]

I wondered how they function when the rear mech is covered in mud. Are they not prone to delays or non-shifts just when you need it most?

no problems so far. and just to show i do get my bike quite muddy...

i clean and oil the chain after every muddy ride, but only clean and oil the mechs once a month or so, same as i did on the previous mech.
​

 

[marcdominic]

Jpem,

I agree, surely having to pull and apply tension to shift the derailleur as you need on an uphill climb, is more reliable than depending on the muddied spring function of high-normal shifters… At least you know you will get the required gear under tension.

Perhaps this functionality suits road bikes more so because of the conditions they may be ridden under…?

 

[bonj2]

my experience is as simon adams uk, i like rapid rise. a non-rapid rise is fine except for situations such as when you're bombing along quite fast and you come across a short sharp incline, fairly suddenly, and have to change down quickly to power up it (such as there is quite a lot of at coed y brenin).
If you only ride on fairly innoccuous terrain that doesn't change gradient very quickly you're probably not likely to see the advantage of RR.

considered having one on the road bike but there wouldn't really be any good reason for it other than contraryness...