105/ST-RS505 downshift adjustment

[scrwright]

Upshifting is perfect, however indexing going down both 1 or 2 shifts is a little off. Had a search but jsu keep finding info on adjusting lever reach, is there a decent idiots guide to adjusting the indexing?

ta

[numtumfutunch]

How old is your kit?

You are describing a worn shifter cable to me............

[scrwright]

shifters/cables are less than a year old (done about 1000km). Was a flat bar trigger shifter bike, moved over to drops. Shifting was fine for first 6 months. Never adjusted anything on the bike at all, even with the switch over it indexed correctly straight away.

[Bobley]

If the shifter and cable are good then it's either a worn chain (too much lateral play) or a slightly misaligned hanger. Once everything else is good then actual trimming of the cable is easy.

If the system is playing up and I've stripped it all out and rebuilt then my trimming method is to take the shift cable off the mech and turn the cranks slowly to ensure the hi end set screw is positioned correctly and then push the mech back by hand and trim the low end. Once thats done, turn the cable adjuster screw all the way in and then 1-1.5 turns back, pull the new cable through by hand and use pliers to pull it fairly taught (ensuring the shift lever is in top gear) and nip up the clamp screw. If you've done all that properly then you should find the whole lot is set spot on but you should only need to tweek the cable adjuster very slightly.

If you then leave it in a low gear overnight then in the morning you'll probably need to back out another half on the cable adjuster as the cable beds in (stretches)

[scrwright]

looking on strava the chain has done 2400kms, should it be worn on that much?

[numtumfutunch]

scrwright said:

looking on strava the chain has done 2400kms, should it be worn on that much?

Multiple variables to make an accurate guess eg weather, lube. cleaning regime etc etc

However my commuter/winter hack just took an 11sp chain to just under 1% stretch in approx 2000km - which was a personal record TBH and Im now not massively feeling the love for 11sp over 10 speed, at least on my foul weather bike, least of all because the first I knew of it was a snapped chain

A chain measuring tool is well worth having:

http://www.bikeradar.com/road/gear/article/bicycle...

http://www.chainreactioncycles.com/x-tools-chain-w...

[idiotgap]

For the stingy, a 30cm ruler of the type we have a few of lying around the house alreadymakes a handy chain wear tool (this is beginning to sound like viz top tip!).

The theory is sound though, each link is exactly an inch long when the chain is new. To check if it's worn out see how much stretch you have over six inches or twelve. Sheldon describes it here: https://www.sheldonbrown.com/chain-wear.html

[scrwright]

so no stretch over 12" of chain. Could do with a bloody good clean, knew I shouldn't have gone out in the rain on stty roads last week. Will give it all a good clean up first and see if shifting improves

[Bobley]

Cleaning out a mucky worn chain is usually when it all goes to pot. Flushing out the muck in joints which was clogging the gaps apart will leave it all loose.

If you're an all weather winter rider then you should consider alternating between two chains as they wear. This will give you the opportunity to really dip the chain which is off the bike and also it evens out wear on the cassette as a worn chain will wear the cassette down such that a new chain will skip off a worn cog.

[TwilightJohnny]

... or it might just need half a turn clockwise on the adjuster.

[JustinF]

is the chain on the right way round?

[The_Jackal]

Yeah dont you just need to tighten the cable a bit?