Shifting up jumps all the way to smallest cog

[Tin Pot]

driving me nuts as I'm supposed to be training.

Haven't played with the rear derailleur since flying back from Ireland and I rmembemr someone advising on this problem.

Shifting down is fine, if a little grindy.

Shifting up clunks and jumps all the way to the smallest cog!

Tried playing with rear cable tensioner - shifting down gets smoother but shifting up still jumps all the way.

HELP!

I've got 2.5hrs to do on the turbo before bedtime then up at 5:30 for another hour...

 

[HLaB]

See if you get better advice but if you don't want to be in the hardest gear you could adjust the limit screw so it stops short of the smallest cog. I've had similar in the past but not dropping down through all the cogs and it was a wire end cap beginning to snap inside the hood where I couldn't see it. It quickly snaps altogether though and whilst it will fall to the smallest cog it wont shift to a lager one. Good Luck

 

[Tin Pot]

Tried releasing and resetting the cable - makes no difference - so I've kind of taken your advice and set it in a gear that won't slips. I'll just have to up the cadence to get to the right output

 

[Tin Pot]

1.5hrs in. A few issues but getting through it.

 

[Tin Pot]

Right got some time to sort this out.

When the rear derailleur shifts to he smallest cog, it's loosening the tension, right?

Because if the cable is disconnected it falls to the smallest.

So there's likely some problem with how much the shifter is releasing.

From biggest cog, one click jumps down two. The second click jumps all the way to the smallest.

 

[lpretro1]

Suggest u fit a new cable inner & outer

 

[Glow worm]

New inners and outers is a good shout. Don't forget to adjust the barrel adjuster as well. I found this video useful.

 

[winjim]

Right got some time to sort this out.

When the rear derailleur shifts to he smallest cog, it's loosening the tension, right?

Because if the cable is disconnected it falls to the smallest.

So there's likely some problem with how much the shifter is releasing.

From biggest cog, one click jumps down two. The second click jumps all the way to the smallest.

Try disconnecting the mech and pulling on the cable as you click the shifter through the gears. Hold it by the downtube stop to eliminate any effects from that last piece of cable outer. You should be able to feel the cable release with each click. That should let you know if it's a shifter problem.

 

[ColinJ]

There must be a ratchet mechanism in the shifter which is supposed to release the cable by just enough per click to change up one gear. If the ratchet is worn/broken then it isn't hard to see how it would release the cable completely and cause the problem described. @winjim's suggestion sounds like a good way of checking for that.

 

[Tin Pot]

Try disconnecting the mech and pulling on the cable as you click the shifter through the gears. Hold it by the downtube stop to eliminate any effects from that last piece of cable outer. You should be able to feel the cable release with each click. That should let you know if it's a shifter problem.

This is what I've just done(!)

Click, click...clackety.

I've lifted the rubber over the shifter and watched it jump there too.

Shame as I was sure it would be related to my removing/replacing the rear derailleur for those flights to/from Ireland.

Will it be lube? A spring? Or replace (I have spares).

 

[Tin Pot]

Correlating the advice , searching for "worn out Veloce shifter" gives me this:

http://bicycles.stackexchange.com/questions/29860/rear-derailleur-shifts-all-gears-at-once

Which says it's a g spring failure - only replaceable on pre 2007 Veloce shifters.

Lucky I have a spare set of new Veloce shifters

I wanted maybe an hour of fettling, not a day!

 

[winjim]

Maybe @Graeme_FK has some advice?

 

[ColinJ]

Correlating the advice , searching for "worn out Veloce shifter" gives me this:

http://bicycles.stackexchange.com/questions/29860/rear-derailleur-shifts-all-gears-at-once

Which says it's a g spring failure - only replaceable on pre 2007 Veloce shifters.

Lucky I have a spare set of new Veloce shifters

I wanted maybe an hour of fettling, not a day!

I didn't know that the springs are not replaceable on later Campagnolo shifters. I have 10-speed Chorus from the early 2000s and the right shifter was losing its indexing last year so I searched YouTube and found a very good Campagnolo video showing how to service it. It is good as new now!

 

[Tin Pot]

Thought i had spare Veloce shifters.

Damn.

Knew I should've gone Veloce on my Tt instead of Athena(!) - I have spare Athena shifters...

 

[kipster]

Thought i had spare Veloce shifters.

Damn.

Knew I should've gone Veloce on my Tt instead of Athena(!) - I have spare Athena shifters...

If they are both 10 speed then the Athens shifters will work. When my Veloce shifters did the same thing I put on some centaur shifters. Also if the Veloce shifters are under 2 years old you can get them repaired under warranty.