Gear issues

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robert17
Posts: 142
Joined: 24 Mar 2009, 1:41pm
Location: Worcs

Gear issues

Postby robert17 » 6 Oct 2018, 8:35am

People,

I am an average home mechanic but am now a little frustrated. My 105/Ultegra set up is not changing as well as I'd like. In essence moving to an easier sprocket is hesitant on gears 6-10, but fine 1-5. I have changed cables and gone through the usual barrel adjuster caper, but no joy. It is not awful and an managing but know if could be better. Any ideas? Thank you.

Robert.

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Cugel
Posts: 2456
Joined: 13 Nov 2017, 11:14am

Re: Gear issues

Postby Cugel » 6 Oct 2018, 9:41am

robert17 wrote:People,

I am an average home mechanic but am now a little frustrated. My 105/Ultegra set up is not changing as well as I'd like. In essence moving to an easier sprocket is hesitant on gears 6-10, but fine 1-5. I have changed cables and gone through the usual barrel adjuster caper, but no joy. It is not awful and an managing but know if could be better. Any ideas? Thank you.

Robert.


Robert,

Gear adjustments for derailleurs require the fettling of a number of things, not just the barrel adjuster and cable attachments or path. There are dozens of how-tos on the interweb that will show you all the steps and operations of adjustment. Pick the one(s) that are most clear to your preferred education-absorption modes.

There are a few things about the design of the frame that can make it harder to adjust rear derailleurs to their optimum, notably chainstay length. Very short chainstays mean bigger angles-of-deflection of the chain, for example. There can also be problems if the chainline is not central to the cassette because of a strange bottom-bracket width or an unusual rear drop-out gap.

Sometimes the gear parts themselves can be an issue. Sticky cables in outers, guides or around bends; slightly bent rear derailleur jockey-wheel arm; dirt-jammed jockey wheel.

All those things need looking at and, if necessary, fettling.

CUgel

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foxyrider
Posts: 4511
Joined: 29 Aug 2011, 10:25am
Location: Sheffield, South Yorkshire

Re: Gear issues

Postby foxyrider » 6 Oct 2018, 10:46am

Bicycle mechanics are aBlack Art, if you don't have all the components of the spelljust so nothing will work optimaly and any error will come back to haunt you sooner or later.

Amateur mechanics are but mere acolytes to the Grand Masters, 8) :lol:
Convention? what's that then?
Airnimal Chameleon touring, Orbit Pro hack, Orbit Photon audax, Focus Mares AX tour, Peugeot Carbon sportive, Owen Blower vintage race - all running Tulio's finest!

Brucey
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Joined: 4 Jan 2012, 6:25pm

Re: Gear issues

Postby Brucey » 6 Oct 2018, 10:47am

presumably this is a 10s setup? It may just need adjusting; as simple as a half-turn on the barrel adjuster on the mech, or a turn on the b-tension screw.

However it might also just be worn out; have you checked the chain for wear?

cheers
-------------------------------------------------------------------------------
~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

peetee
Posts: 1358
Joined: 4 May 2010, 10:20pm

Re: Gear issues

Postby peetee » 6 Oct 2018, 11:19am

Could be any number of things but a good start would be to check the condition of the cable outers, particularly the ends of the metal strands inside the end caps.
Current status report:
Latter side of fifty and feeling less than nifty.
Too many bikes on pegs and too few miles in the legs.

robert17
Posts: 142
Joined: 24 Mar 2009, 1:41pm
Location: Worcs

Re: Gear issues

Postby robert17 » 6 Oct 2018, 7:48pm

Many thanks, chain is a nearly new SRAM and cabling is new too. I may check though as it is the long route (CX bike).

Brucey
Posts: 35536
Joined: 4 Jan 2012, 6:25pm

Re: Gear issues

Postby Brucey » 6 Oct 2018, 8:36pm

FWIW SRAM 10s chains are not always quite as they are meant to be. Recently I have enountered two that did weird things;

The first was marking up the neighbouring sprockets (in a SRAM 10s cassette), in a way that I have only seen when 9s chain is used on a 10s cassette.

The second, even though it was new, was changed as a last resort when a system that ought to have worked OK didn't want to play ball nicely. Once a KMC chain was installed, the shifting was just fine.

When measured, both SRAM chains were between 6.1mm and 6.2mm wide, which is significantly wider than 10s chain ought to be.

One of the side effects of this was that there was genuinely zero tolerance for the RD being misaligned in one direction. Another appears to be that the shifts were baulky and didn't want to go any time the guide pulley was even a moderate distance from the sprockets.

Some things to check;

- that the chain isn't wider than it should be
- that the gear cable is correctly installed at the pinch bolt
- that the RD isn't misaligned
- that the cables are in good shape
- that the cassette does have the conventional sprocket pitch (eg plastic spacers can settle to new dimension)
- that the RD moves the correct amount when the shifter is used
- that the pivots in the RD are not worn (slop in the upper pivot is not well tolerated)
- that the guide pulley is in good shape

If you run out of good ideas, just try changing the chain. Worst case is that you end up with a spare chain.

cheers
-------------------------------------------------------------------------------
~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

robert17
Posts: 142
Joined: 24 Mar 2009, 1:41pm
Location: Worcs

Re: Gear issues

Postby robert17 » 4 Jan 2019, 8:16pm

Many thanks for these. After a suggestion elsewhere of a bent hanger, this was a revelation for around 150 miles. No, back to skipping, jumping and all round crapness. Could it be the shifter. It is a 105, second hand. Really don't want to spend any more money!! Thank you.

thelawnet
Posts: 2198
Joined: 27 Aug 2010, 12:56am

Re: Gear issues

Postby thelawnet » 4 Jan 2019, 9:45pm

I doubt the shifter is at fault. Presume you have set the b screw & H screw?

When I had shifting problems it turned out to be a damaged freehub.

robert17
Posts: 142
Joined: 24 Mar 2009, 1:41pm
Location: Worcs

Re: Gear issues

Postby robert17 » 4 Jan 2019, 10:25pm

Thanks, yes pretty sure they are okay. Seems that I get it working okay and then over what can be just ten or twenty miles it goes off again, like something is slipping out of sync.

LittleGreyCat
Posts: 562
Joined: 7 Aug 2013, 8:31pm

Re: Gear issues

Postby LittleGreyCat » 4 Jan 2019, 11:02pm

robert17 wrote:Thanks, yes pretty sure they are okay. Seems that I get it working okay and then over what can be just ten or twenty miles it goes off again, like something is slipping out of sync.


Once it goes off, does it stay that way for the start of the next ride, or does each ride start out OK but then go off after 10 miles or so?

peetee
Posts: 1358
Joined: 4 May 2010, 10:20pm

Re: Gear issues

Postby peetee » 4 Jan 2019, 11:27pm

If you have gear cables running under the bar tape it could be that the application of securing tape or the bar tape has pulled the outer cable tight to the bar and away from the seat of the shifter. It's possible to create a gap of around 5mm on particularly tight bend bars and the adjustments you are making may be because the outer cable is creeping back towards the shifter. That's not to say it will eventually rectify itself because on many sti shifters the cable path isn't as smooth as it should be.
Last edited by peetee on 5 Jan 2019, 10:34am, edited 1 time in total.
Current status report:
Latter side of fifty and feeling less than nifty.
Too many bikes on pegs and too few miles in the legs.

Canuk
Posts: 1105
Joined: 4 Oct 2016, 11:43pm

Re: Gear issues

Postby Canuk » 5 Jan 2019, 8:27am



I'll post this again, so you can bow down to the god of Electronic gear shifting. :lol: It's mesmerising. Watch how the front mech moves as if by telepathy to the ideal position. This is why I gave up with cables and outers, and ferrules and rust and lubricants and constant adjustment. I have an Ultegra version of this which has worked flawlessly over no idea how many thousands of perfect shifts without any additional adjustment for 5 years now, through the roughest - 35C Canadian slush filled winters also without so much as a shiver. Shimano are set to release a semi wireless version of this kit which means even the most technology averse can fit it in half an hour. I also managed to cobble together a perfectly working system for my winter bike of 3 years for roughly 300 euro from shrewd buys on ebay. I use this every day and treat it very roughly and it just keeps on working. Flawlessly.

I reckon when the roll Di2 out to 105, or FSA or SRAM come up with a more budget system it's game over for mechanical shifting. One thing, like screw on cassettes I'll be glad of its demise.

thelawnet
Posts: 2198
Joined: 27 Aug 2010, 12:56am

Re: Gear issues

Postby thelawnet » 5 Jan 2019, 8:43am

Canuk wrote:

I'll post this again, so you can bow down to the god of Electronic gear shifting. :lol: It's mesmerising. Watch how the front mech moves as if by telepathy to the ideal position. This is why I gave up with cables and outers, and ferrules and rust and lubricants and constant adjustment. I have an Ultegra version of this which has worked flawlessly over no idea how many thousands of perfect shifts without any additional adjustment for 5 years now, through the roughest - 35C Canadian slush filled winters also without so much as a shiver. Shimano are set to release a semi wireless version of this kit which means even the most technology averse can fit it in half an hour. I also managed to cobble together a perfectly working system for my winter bike of 3 years for roughly 300 euro from shrewd buys on ebay. I use this every day and treat it very roughly and it just keeps on working. Flawlessly.

I reckon when the roll Di2 out to 105, or FSA or SRAM come up with a more budget system it's game over for mechanical shifting. One thing, like screw on cassettes I'll be glad of its demise.


cool story bro.

Canuk
Posts: 1105
Joined: 4 Oct 2016, 11:43pm

Re: Gear issues

Postby Canuk » 5 Jan 2019, 9:13am

thelawnet wrote:
Canuk wrote:

I'll post this again, so you can bow down to the god of Electronic gear shifting. :lol: It's mesmerising. Watch how the front mech moves as if by telepathy to the ideal position. This is why I gave up with cables and outers, and ferrules and rust and lubricants and constant adjustment. I have an Ultegra version of this which has worked flawlessly over no idea how many thousands of perfect shifts without any additional adjustment for 5 years now, through the roughest - 35C Canadian slush filled winters also without so much as a shiver. Shimano are set to release a semi wireless version of this kit which means even the most technology averse can fit it in half an hour. I also managed to cobble together a perfectly working system for my winter bike of 3 years for roughly 300 euro from shrewd buys on ebay. I use this every day and treat it very roughly and it just keeps on working. Flawlessly.

I reckon when the roll Di2 out to 105, or FSA or SRAM come up with a more budget system it's game over for mechanical shifting. One thing, like screw on cassettes I'll be glad of its demise.


cool story bro.


All gravy, Deed.