Problem with 105 set up

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ANTONISH
Posts: 2967
Joined: 26 Mar 2009, 9:49am

Problem with 105 set up

Post by ANTONISH »

I've had a Shimano 105 triple set up all running well.
The chain needed renewing - new KMC for old Sram.
I noticed that the cable for the rear derailleur was frayed and I changed it.
The new inner seemed "draggy" and the changing was poor. I changed the outer at the derailleur which seemed to improve things
I sprayed some WD40 into the shifter and then some light spray grease .
Although things work OK on the stand, on the road I'm still getting ghost shifts - not all the time but enough to be an irritation. The chain doesn't appear to be skipping on the cassette rather I seem sometimes to be between changes and have to do double shifts. I still haven't changed the outer at the shifter.
The outer cable is 4mm and I did read somewhere that 5mm is preferable - I'd be grateful for any advice.
Brucey
Posts: 44517
Joined: 4 Jan 2012, 6:25pm

Re: Problem with 105 set up

Post by Brucey »

inner cables vary; which kind did you use? What do you mean by ghost shifts exactly (it means different things to different people). Dragginess with a new inner may indicate various things including;

- bad prep on new cable housing
- worn old cable housing
- debris in old cable housing
- lube on new cable is wrong (absent or too thick)
- new inner isn't smooth enough
- new inner is kinked inside housing
- new inner cable is binding in (worn) cable guide under BB

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
pwa
Posts: 17367
Joined: 2 Oct 2011, 8:55pm

Re: Problem with 105 set up

Post by pwa »

It isn't likely to be the new chain, so it looks like something about the new cable / outer is draggy. Or is it simply that the pinch bolt at the rear mech is not done up enough to hold the cable and the cable is constantly sliding past it, going out of index?
reohn2
Posts: 45158
Joined: 26 Jun 2009, 8:21pm

Re: Problem with 105 set up

Post by reohn2 »

Did you change the front outer casing from shifter to frame stop?
If not that could be your problem.
When changing cables I always use Weldtite red grease on the inner and ensure it's slick in the outers on assembly.
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"All we are not stares back at what we are"
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David9694
Posts: 908
Joined: 10 Feb 2018, 8:42am

Re: Problem with 105 set up

Post by David9694 »

Cable tension? in the highest gear you should be able to get the next cog down with one click. I find half a turn on the barrel adjuster works wonders with ghost changes (which are usually up].

Also don’t forget that new ferrules sometimes need to bed in to their new home.

IIRC 4mm outer is correct for indexed gears.
Spa Audax Ti Ultegra; Genesis Equilibrium 853; Raleigh Record Ace 1983; “Raleigh Competition”, “Raleigh Gran Sport 1982”; “Allegro Special”, Bob Jackson tourer, Ridley alu step-through with Swytch front wheel; gravel bike from an MB Dronfield 531 frame.
ANTONISH
Posts: 2967
Joined: 26 Mar 2009, 9:49am

Re: Problem with 105 set up

Post by ANTONISH »

Thank you all for the replies.
All points toward the outer from the shifter which I'm going to replace.
I hadn't thought about the BB cable guide but that seems in good condition.

It occurs to me that I had a problem with the LH shifter (front changer) earlier in the year.
The wires of the housing had worked through a plastic ferrule at the shifter and this gave problems shifting to the large ring - initially I thought the band on front changer was slipping.
Not having any 4mm to hand I used an unused pre-cut 5mm outer for a bar end changer. This had metal ferrules.
It worked and I had forgotten about it. I'll replace that with 4mm but I'm using metal ferrules.
Brucey
Posts: 44517
Joined: 4 Jan 2012, 6:25pm

Re: Problem with 105 set up

Post by Brucey »

IME plastic ferrules often fail if you are not suitably diligent with cable prep. I will use plastic ferrules but only if they are a snug fit and the housing that goes in them is ground square; cut ends, when examined, usually show the ends of each wire being like little chisels, just ready to gouge into the plastic ferrule. Metal ferrules are great but they can fret in some fittings and are a very loose fit in others, simply because they are thinner walled. Often the best choices are 4mm housing with plastic ferrules or 5mm housing with metal ferrules.

If you want to do a 10/10ths job, you should hold the (non spiral type) gear housing curved into the final shape, and check/grind the ends square in that attitude; this ensures that the ends really are square. Unless you do this you will sometimes find that a cable has ends that are slightly angled when it is curved into the final shape.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
peetee
Posts: 4292
Joined: 4 May 2010, 10:20pm
Location: Upon a lumpy, scarred granite massif.

Re: Problem with 105 set up

Post by peetee »

Are they 5700 shifters? These have a gap in the lever body behind the hood which, if you often grip the hoods tight, can cause the rubber to be shaven off and get into the shifter mechanism. The damage is clear to see if you peel the hoods back.
The older I get the more I’m inclined to act my shoe size, not my age.
ANTONISH
Posts: 2967
Joined: 26 Mar 2009, 9:49am

Re: Problem with 105 set up

Post by ANTONISH »

Thanks once again for the replies.
I replaced the housing at the shifter - used metal ferrules.
All working OK.
How things have changed from down tube shifters - in fact my first front mech was lever operated - you had to reach down to change it - nice positive action though.
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