Can't get onto largest chainring
W1368
Posts: 9
The bike was serviced about a month ago, along with newly fitted cables.
All was running smoothly until a wet trail ride. It is impossible to shift onto the largest rear cog, the shifter is rock solid at this point and feels more like it's gone past the last click (display shows one more to go). The shifts between the smallest cogs are a bit strange. Won't go from 2nd smallest with one click, but will go from 3rd smallest with two clicks in one sweep.
I checked the limit screws and they seem spot on. With the cable detached the derailleur can move all the way through the cassette and the chain doesn't go too far at either end.
Tried for ages getting the indexing set right with the front barrel adjuster, I can get it to a usable tension but individual changes are poor, changing a couple or more gears at once seems to work.
Cleaned the cables, and checked for any sharp bends. The outers slide fairly smoothly and I can't see any crud in there.
Front derailleur running perfectly. Checked for chain wear, currently at 0.75% and already have a new one ready to fit.
It's an entry-level bike (already knackered from fork) but gears were working perfectly when it came back from the LBS.
Shimano SL-M370-9R
Alivio RD-M4000
Full bike components are shown near end of this page: http://mountain-bikes.gearsuite.com/l/9626/2015-Scott-Aspect-940
Cheers!
All was running smoothly until a wet trail ride. It is impossible to shift onto the largest rear cog, the shifter is rock solid at this point and feels more like it's gone past the last click (display shows one more to go). The shifts between the smallest cogs are a bit strange. Won't go from 2nd smallest with one click, but will go from 3rd smallest with two clicks in one sweep.
I checked the limit screws and they seem spot on. With the cable detached the derailleur can move all the way through the cassette and the chain doesn't go too far at either end.
Tried for ages getting the indexing set right with the front barrel adjuster, I can get it to a usable tension but individual changes are poor, changing a couple or more gears at once seems to work.
Cleaned the cables, and checked for any sharp bends. The outers slide fairly smoothly and I can't see any crud in there.
Front derailleur running perfectly. Checked for chain wear, currently at 0.75% and already have a new one ready to fit.
It's an entry-level bike (already knackered from fork) but gears were working perfectly when it came back from the LBS.
Shimano SL-M370-9R
Alivio RD-M4000
Full bike components are shown near end of this page: http://mountain-bikes.gearsuite.com/l/9626/2015-Scott-Aspect-940
Cheers!
0
Comments
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Check shifter moves properly just tugging on the cable, with it disconnected.
Check hanger isn't bent.
But if they used cheap cables they could be stuffed already. Replace with good quality (Shimano SP41 outers are good) and stainless inners.
Read Parktools and index correctly.
That's about all there is.I don't do smileys.
There is no secret ingredient - Kung Fu Panda
London Calling on Facebook
Parktools0 -
Squirt some WD40 type stuff in the shifter, the rachets may be sticking.
Otherwise, those shifters have a habit of deforming the actuator plate.
Pull it apart and make everything look like it is straight and working smoothly.
If you don't want to waste 15min of your time, just get a new one.
Also check for fraying of the cable inside the shifter.0 -
Don't squirt WD40 in to the shifter. It will dissolve any grease that may already be there.
WD40 is not a lubricant.
Do what cooldad suggests: read Parktools, watch a video or two and then start from scratch.“Life has been unfaithful
And it all promised so so much”
Giant Trance 2 27.5 2016 ¦ Sonder Broken Road 2021¦ Giant Revolt Advanced 2 2019 ¦ Giant Toughtroad SLR 1 2019 ¦ Giant Anthem 3 2015 ¦ Specialized Myka Comp FSR 20090 -
Its not one of those shifters with a latch to convert a 3 to a 2 is it......Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.0
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Its not one of those shifters with a latch to convert a 3 to a 2 is it......Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.0
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Could you convert your post from a 2 to a 3?
But he's talking about the rear/cassette, not the front.I don't do smileys.
There is no secret ingredient - Kung Fu Panda
London Calling on Facebook
Parktools0 -
Sorry, misread as he used the word chainring which is of course front only!Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.0
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This shifter is well known to gum up and bend the plate.
Give it a squirt and straighten the plate, put a couple of drops of oil or very light grease like slick honey afterwards if you like.0 -
Couldn't get cover off without taking it off bar, it was late and didn't have time to get brake lever off.
Anyway, the screw covering the cable end is missing from the shifter????
It's a pretty large opening, that thing must be filled with all sorts of dirt and water in there.
I'll take it back to the bike shop.0
