Ghost shifts

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redvee
Posts: 11689
Joined: Tue Oct 09, 2007 22:03 pm

Ghost shifts

Postby redvee » Sat Apr 06, 2013 22:39 pm

I know this is common on full sus bikes and those badly set up with short outer runs but this is on my Kaffenback with plenty of outer between levers and frame and from the frame to rear mech. Could the ghost shifts be a sign of worn ratchet in the STI levers? What confuses me is that sometimes it will shift one way, from a larger to smaller sprocket, other times from small to a larger sprocket. The STIs are approx 4 years old and untouched by me, tonight I've given it a short spray of degreaser and will lube with GT85 in the morning.

maringirl
Posts: 193
Joined: Thu Oct 11, 2012 13:46 pm

Re: Ghost shifts

Postby maringirl » Sun Apr 07, 2013 09:57 am

Sounds just like a cable sticking?

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redvee
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Re: Ghost shifts

Postby redvee » Sun Apr 07, 2013 10:40 am

It's a new build, will check the outers after the riders arrive in the Belgian veledrome later.

DesWeller
Posts: 5233
Joined: Mon May 05, 2008 15:36 pm

Re: Ghost shifts

Postby DesWeller » Sun Apr 07, 2013 14:29 pm

Check that the hanger's straight and not loose. I've had some dodgy bits from PX in the past in this area.

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redvee
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Re: Ghost shifts

Postby redvee » Sun Apr 07, 2013 15:56 pm

DesWeller wrote:Check that the hanger's straight and not loose. I've had some dodgy bits from PX in the past in this area.


Done that already before I built it as I secured the bolts with a dab of threadlock. Outers are running free on the inners. What makes me think the gear levers are at fault is that it's only the middle 3 gears it happens in.

DesWeller
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Joined: Mon May 05, 2008 15:36 pm

Re: Ghost shifts

Postby DesWeller » Sun Apr 07, 2013 17:19 pm

Is it a new rear derailleur? It's pretty unlikely but perhaps the return spring in the mech is not strong enough.

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redvee
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Re: Ghost shifts

Postby redvee » Sun Apr 07, 2013 22:56 pm

In the workshop/kitchen/living room it changes OK both up and down, might look in the classifieds for a new/better mech.


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