bleumeon

Hi,

I have a shimano 5800 groupset (only about a 100 miles or so on it) on my trek emonda alr 5 that's giving me small shifting issues.

The shifting is very precise and quiet except for the first 3 sometimes 4 gears when shifting down (from smaller gears shifting to larger gears). There is a little lag there the chain fails to snag on the next gear for a brief period. After the fourth gear the shifting is very precise and smooth. Cable tension is set right and adjusting the barrel adjuster does not make any difference. I ensured my limit screws weren't over tightened either to prevent shifting lag.

This lead me to believe it was my b-tension screw. Given that the pulley cogs are further from the cassette in the high gears vs low gears shifting would be inevitably worse. Even when loosening the b-tension considerably there is no significant improvement and of course loosening the b-tension too much causes the pulley cogs to hit the cassette in my low gears. I aligned my hangar too and I know it's dead straight.

Does this mean my pulley cage is bent? Or the derailleur cage itself? Something with the cables?? I lubed all my cables with a good quality oil and they all seem to move fine. For a new bike with no crashes and no visually discernible damage I'm at a lost. What would be the issue for poor down shifting only on the first 3 gears?

Thanks,
Bleumeon

ammarolli

One friend of mine always had some shifting problem with his bike until he got new frame.
It's sounds like your chain needs to replaced but that should not be that case for a new bike.

cny-bikeman

Have you asked the selling shop for an assist? Should still be on adjustment warranty. If you think that limit screws would have any effect when shifting to larger gears from the small cogs then it would seem you need a more experienced person to look at the bike.

Bill Kapaun

Are you on the largest ring?
Maybe a 1/2 turn (or so) out on the barrel adjuster?
You can go out until the opposite problem occurs and go back 1/2 of that, for a happy medium.

Scooty Puff Jr

I had the same issue, drove me crazy because my bike was brand new (2016) with all Alivio components. I adjusted and adjusted everything, had two different mechanics try with no luck, even replaced the shifter with no luck. In desperation I replaced my KMC chain to a Shimano chain and it cleared the problem, and now all my shifts are perfect.

Don't ask me why because I've used KMC chains with Shimano components in the passed with no problems.

bleumeon

I was talking about down shifting from smaller to larger gears. When over tightening the limit screws sometimes the shifting can become less smooth.

bleumeon

The chain on my bike is a HG-X11 shimano chain. Could a new chain be at fault?

Scooty Puff Jr

I don't know, but you are describing the exact same problem I had on my bike. Changing the chain was a blind $25 gamble that ended up working out. Maybe your chain is a link or two short or long ?

bleumeon

Is a long or short chain a possible issue on a new bike? I did just throughly clean my chain and shifting quality improved but there are still some bad shifts here and there. It very may well be the chain but considering I only have 100 miles on the bike so far it seems unlikely.

Scooty Puff Jr

Well, I had less than 100 miles on my bike too. Count the links, maybe they put the wrong size chain on it at the factory ? Anyhow, I know how you feel, it's very flustrating getting a new bike and having issues that are a headache to figure out.

cny-bikeman

Chain length is not the problem, just silly to think so.

tcpasley

Make sure your cassette lockring is properly tightened. Make sure you haven't mixed up 10 speed loose cogs on your 11 speed cassette (not likely if it's a brand new bike). And check for a kink in your cable that might be hidden inside the housing near the derailleur. I had that problem and it drove me nuts for a week until I changed out the cable. I've had flawless shifting since then.

Andrew R Stewart 

Limit screws only effect to cogs, the smallest and the biggest. Any shifting issues that include other cogs are not due to limit screws (unless the limit screw is so far run in it effects the next cog over. But then this next cog becomes the "last" cog of sorts)


Chain length can and does effect shifting speed if the length is such that the gap from the cog underside and the top of the guide pulley is a large one, so that a number of chain links span this gap. The more chain links (actually the pivots of the chain) that are between the cog and guide pulley the greater the chain will just flex sideways before it tries to engage the next over cog. Just watch the cage rotation and this gap when you shift from the small ring to the large one sometime.


As the der moves to the small cog end of the cassette the parallelogram spring is also reducing it's tension. It's ability to pull against the cable's friction lessens. If cable friction is enough (grit/grime, cable fraying, bad internal routing path, rust on cable, bad casing ends/caps) the shifting will degrade as the der moves toward the larger gears (which are the smaller cogs, just to keep terms straight).


Bent hanger of cage pivot also can cause this. Both are easily detected by a good and experienced eye. I don't rely on a hanger alignment tool to set the hanger as many ders have some mounting bolt off axial wobble as you thread it into the hanger. So it's possible to have a hanger be "tool aligned" but not "der aligned".


The last case I'll mention is not common but has happened a few time IME. The typical guide pulley has a bit of side to side float (end play in the bushing/bearing) to allow the pulley to better track under each cog. I have seen a few guide pulleys where the bushing was crudded up enough to hinder this tolerance absorbing feature (as in tolerance of chains running less straight or cogs not being either flat or evenly on center across the cassette range.


But I'll say that cable friction is a BIG reason, very common. The comment about the cable adjuster ("and adjusting the barrel adjuster does not make any difference") having little effect points to this. If the system is in good order a full turn of the adjuster barrel should make a significant difference. Andy.

Zef

Based on your description I would recommend having your derailleur hanger alignment checked. An often indicator that it needs to be realigned is that one can dial in the shifting for the top or bottom half (or third) of the gears on the cassette but cannot dial in the entire range of gears.

The hanger does not need to be misaligned much to have a dramatic affect on shifting. Standard tolerance for alignment is less than or equal to 4mm when comparing measured points opposite each other at the rim (using the correct tool)....which equates to a very small amount of down at the hanger.

The b-screw, limit screws, and tension adjuster will most likely not help except frustrate you to the point that you either buy an alignment tool or take it to a shop to have it done.

If you are at all skilled with tools, I recommend to buy the tool...it will pay for itself over the course of a few years (or less).

-j

Scooty Puff Jr

Umm, no, incorrect chain length can cause the OP's problem. I doubt that is his problem, but make sure it isn't and he eliminates at least one possibility.

bleumeon

I do have an alignment tool which is why I know the hangar is aligned.

Right now the suspected causes is the cables or pulley cage. This issue is primarily only when down shifting for the first 3 or 4 shifts. Smaller to larger cogs.


How can I remove the cable to check for kinks?

bleumeon

Thanks for this detailed reply. As you say the derailleur itself may not be in the same plane as the hangar so even with my hangar straight there is still a shifting issue.

I think my quide pulleys are clean, I did lube em with some boeing T-9 several weeks ago but as a dry lubricant I can't imagine it crumming up so much.

As for cable friction this could be the issue. But my up shifting (from larger to smaller cogs) works just fine and its only when I'm down shifting (from smaller to larger cogs) for the first 3 or 4 shifts.


I'm trying to see if I can get a local lbs to help me out. When I asked the bike shop about this issue where I purchased the bike from they said its probably just the b-tension screw which I know isn't the problem.

bleumeon

Well I examined my cable today and pulled it out of the casing. No issues at all and very smooth. I cleaned and degreased it and added a thin layer oil that I let dry before siding the casing back over. So for sure I know its not my cables. After the cleaning they are even better than before. As far as indexing and messing with the barrel adjuster there is no setting that will fix the current issue without causing another--this is even with super small incremental turns.

B-tension does not make a different even when fully loosened. My hangar is tool aligned but as mentioned by Andrew not necessarily derailleur aligned. Visually I cannot find any noticeable deviations from the plane of the cassette. Because of this I believe there is either 1) An issue with my pulley cage 2) To much play on the derailleur bolt or 3) A problem with the chain.

Maybe another useful bit of information is that sometimes I will get good shifts on my first 3-4 gears but it's more bad than good. I thoroughly cleaned my cassette and chain and checked for any play in the cassette. Visually I cannot find anything wrong with it and it feels very solid too. For the heck of it I'm going to test out a new chain and see if it makes a difference. When I get time I'll mess with the hangar to and bend it very lightly in or out to see possibly the derailleur itself just isn't in the same plane.

bikeman715

Maybe the derailleur got damage during shipment ??? one way to know for sure is to try another derailleur , if still have the same problem then you know it not the derailleur . Are you sure the derailleur is tighten to the hanger and the hanger is to the frame ??? maybe the derailleur 's cage is bent or there too much play in the derailleur itself .

bleumeon

I checked to see if the hangar was secured properly and it was. The derailleur is well secured to the hangar as well. There is some play between the derailleur and its hangar bolt but its very minimal. Given that this is a rotating piece there must be some tolerance and can't be perfectly tight. I don't think this is a problem here.

In any case the shifting is decent after a lot of tweaking but not perfect. Whats strange was that the original issue was that shifting was good on entire range for small chainring but bad on large chainring--most people told me that my hangar was probably bent. When I checked alignment with a hangar tool this was the case and after aligning it shifting improved but was still wasn't quite good on the large chainring. I rechecked hangar alignment many times but as far as I could tell it was straight. Now after riding and tweaking it a bit shifting is better on the large chainring but now shifting was poor on the down shifts for the first few gears on the small chainring too leading me to make this thread. In short the current issue is bad down shifting for the first few shifts ( small to large cog ) on both chainrings.

This one time when I was riding the bike my chain did bump the curb knocking it off the inner chainring. I stopped immediately and as far as I can tell there is no damage. Perhaps the chain could of been damaged then?

After I compare with a new chain I'll know for sure. And if that's the case either the frame or the derailleur itself has some defect. At which then I'll try to talk with my local lbs more. Should the derailleur be defective does shimano's warranty give replacements?

bikeman715

Yes Shimano does have a warranty on new parts . maybe this will help , Warranty .

bleumeon

Cool well I should be able to narrow down the problem after I check my chain. Next time I get a free weekend I'll head down to my local lbs to see if they can check things like alignment or if there is any unusual play.

bikeman715

I glad to be of help . I hope you can figure it out .

bleumeon

Well I examined my chain position more and it might be ever so slightly titled outwards. This would explain the difficulty in down shifting to larger cogs. As far as I can tell my derailleur hanger is dead straight though. This would mean the derailleur sits slightly out of plane when mounted to the hanger. I don't have access to any of my tools right now so maybe in a few weeks or so ill adjust the hangar with the derailleur position in mind and see if it makes any difference. In bending the hangar I need to make sure I don't deteriorate the quality of my up shifting (to smaller cogs)

Its hard to imagine a new derailleur being bent thoroughly studying the derailleur I can't find any deformations or out of plane rotations.
New chain coming in 2 weeks so I'll be able to test that too. Hopefully within the next month this is all sorted out.

Homebrew01

No, the limit screws are to limt the derailleur travel, to reach the largest and smallest cog, without overshifting into the spokes, or beyond the smallest cog. Once they are set, they have no effect on shifting quality or smoothness of the rest of the gears.