# How to tell when chainring is worn?



## thisisthebeave (Aug 30, 2015)

I have a narrow wide chainring (Race Face, 40 tooth) on my cross bike and I think it might be nearing replacement time. It is skipping under load but only really high load (like standing on a climb steep enough to be in the easiest 2-3 gears).

In case it is related I wanted to include that I just put a power meter on this bike and I had to adjust the derailleur afterwards. The crank uses a proprietary crank spindle which needed a different combination of spacers than the stock one to fit right so I think the chainline may be a hair different. 2 clicks clockwise on the barrel adjuster got the derailleur perfect so any difference was a small one. Just wanted to include this in case it was relevant.

The chain is not stretched whatsoever and the cassette is in great shape according to my Rohloff cassette wear indicator (both have <500 miles anyway, chainring is around 2k miles). See pic. The black finish on the teeth only lasts a few rides so that isn't really an indication of wear.


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## Mike T. (Feb 3, 2004)

Those chainring teeth look perfect to me. I very much doubt that the skipping is chainring related as they have to be *very* worn for that to happen. 2000 miles for a chainring? They las way longer than that. My current ones have about 14K on them and they still look perfect too.

A worn chainring has hooked teeth and the last one I knew of that really did skip was worn down to nubs and the rider went over the bars when it skipped.


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## ericm979 (Jun 26, 2005)

That's not worn. Just the anodizing on the teeth is worn but the teeth look fine. Worn chainrings have a hooked look to the teeth- they're worn on one side. If you put a new chain on worn chainrings they make a kind of grinding/rumbling noise while pedalling.


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## Peter P. (Dec 30, 2006)

I agree with Mike T. and ericm979; it ain't the chainring.

I've never had a chainring skip, worn or new.

You COULD have a bent tooth on the chainring. Worn teeth on chainrings usually manifests itself with chainsuck or poor downshifting where, as the chain drops from the large to the small ring, it delays dropping onto the small chainring teeth-it rides on top of the teeth momentarily.

I think something else is going on.


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## thisisthebeave (Aug 30, 2015)

I don't know if it is the chainring that is skipping. It feels like the cassette area, but the cassette and chain are new. This bike gets ridden in pretty destructive environments (wet and sandy) where chains usually only last ~500 miles and cassettes a little over 1k miles, so a chainring at 2,000 miles wouldn't be THAT crazy. Narrow/wide 1x mountain bike chainrings often wear out in the ~1,000 mile range.


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## Mike T. (Feb 3, 2004)

To quote Peter, "it ain't the chainring".


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## Peter P. (Dec 30, 2006)

How about the pawls on your cassette body are failing to engage or one of the pawls are broken? Try swapping in a different rear wheel-borrow one if you have to- and see what happens.


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## Lombard (May 8, 2014)

Mike T. said:


> To quote Peter, "it ain't the chainring".


^^^This^^^

Are you sure the skipping is the front, not the rear? I would say it's as simple as a rear derailleur adjustment or possible a bent derailleur hanger. Front rings generally don't skip. If they are worn enough to do that, the chain will drop.


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## ghettocop (Apr 19, 2014)

Narrow-wide chainrings wear out much, much faster than normal road chainrings that most of you are talking about. It very well could need replacement. They are machined much differently and the teeth don't tend to get that hooked shark fin appearance. They just stop holding on to the chain like they used to.


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## thisisthebeave (Aug 30, 2015)

ghettocop said:


> Narrow-wide chainrings wear out much, much faster than normal road chainrings that most of you are talking about. It very well could need replacement. They are machined much differently and the teeth don't tend to get that hooked shark fin appearance. They just stop holding on to the chain like they used to.



I noticed that too on yesterday's ride... if I shove down hard with my left foot once and stop, my right foot coming back up quickly on the rebound causes the chain to come up off the ring a little bit and hits the chainstay. I don't think it used to do that... everything on the bike is 6 months old and some of it even less than that (replaced chain/cassette in February)


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## Pirx (Aug 9, 2009)

thisisthebeave said:


> The chain is not stretched whatsoever and the cassette is in great shape according to my Rohloff cassette wear indicator (both have <500 miles anyway, chainring is around 2k miles).


This is a joke, right? Those parts are practically new, and your chainring looks like it.


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## thisisthebeave (Aug 30, 2015)

Pirx said:


> This is a joke, right? Those parts are practically new, and your chainring looks like it.


I've burned up mountain bike narrow/wide rings in as little as 400 miles. There are fewer teeth so obviously it'll wear quicker. So 2,000 on a bigger ring wouldn't be insane to wear out a ring in. The MTB ones show they're worn by dropping chains or making squealing noises. This one is exhibiting symptoms I've never seen so I'm asking.


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## ghettocop (Apr 19, 2014)

Pirx said:


> This is a joke, right? Those parts are practically new, and your chainring looks like it.


Again.........Narrow/wide chinrings are not even in the same ballpark as the road chainrings you guys are getting all up in arms about. Ihave Race Face narrow/wide on my one-by Mountain bike and the narrow-then-wide profile of the very square machined teeth in conjunction with a clutch rear derailleur are intended to hold on to the chain tightly, and prevent chain drop and chain-slap. They wear out very fast depending on tooth count. I have had 30 tooth rings wear out in 350 miles.


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## ghettocop (Apr 19, 2014)

ghettocop said:


> Again.........Narrow/wide chinrings are not even in the same ballpark as the road chainrings you guys are getting all up in arms about. Ihave Race Face narrow/wide on my one-by Mountain bike and the narrow-then-wide profile of the very square machined teeth in conjunction with a clutch rear derailleur are intended to hold on to the chain tightly, and prevent chain drop and chain-slap. They wear out very fast depending on tooth count. I have had 30 tooth rings wear out in 350 miles.


As an aside......the OP probably should have posted this over on MTBR or in the CX forum, cause a chainring wearing out in a thousand miles does not compute to roadie only types.


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## Lombard (May 8, 2014)

thisisthebeave said:


> I noticed that too on yesterday's ride... if I shove down hard with my left foot once and stop, my right foot coming back up quickly on the rebound causes the chain to come up off the ring a little bit and hits the chainstay.



Possibly the chain is just a bit too long? Try taking a link out, but make sure you can still run in the largest cog without binding. Your shifting will be smoother in general.


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## Lombard (May 8, 2014)

ghettocop said:


> As an aside......the OP probably should have posted this over on MTBR or in the CX forum, cause a chainring wearing out in a thousand miles does not compute to roadie only types.



Apparently not. This is news to me about 1x wide/narrow rings. Wear out in 350 miles? Still seems premature to me when you consider how long a 34 ring on a road bike lasts. Then again, road bikes usually don't regularly deal with mud, water and other constant nasties that CX and mountain bikes do.

Yes, I would say post on MTBR or in the Cyclocross forum here and you will get more people in your camp.


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## Keoki (Feb 13, 2012)

Shark fin = worn


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## Roland44 (Mar 21, 2013)

thisisthebeave said:


> See pic. The black finish on the teeth only lasts a few rides so that isn't really an indication of wear.


Looks like new to me...


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## Mike T. (Feb 3, 2004)

thisisthebeave said:


> I've burned up mountain bike narrow/wide rings in as little as 400 miles. There are fewer teeth so obviously it'll wear quicker. So 2,000 on a bigger ring wouldn't be insane to wear out a ring in. The MTB ones show they're worn by dropping chains or making squealing noises. This one is exhibiting symptoms I've never seen so I'm asking.


I'm not buyin' any of this $hit. If stuff wears out in a few hundred miles (a month?) then it's not viable parts or technology. Conditions my @rse. I raced and trained MTB's for years and didn't wear stuff out like that. So what's the benefit to one chainring? If it needs to wear out in a few weeks then my three-ring setup is going to stay. Hey if I don't shift out of the middle ring, I've got a 1-ring system too eh? The two extra rings and the frt derailer is the price I'll pay. I don't need to look hip.


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## ghettocop (Apr 19, 2014)

Mike T. said:


> I'm not buyin' any of this $hit. If stuff wears out in a few hundred miles (a month?) then it's not viable parts or technology. Conditions my @rse. I raced and trained MTB's for years and didn't wear stuff out like that. So what's the benefit to one chainring? If it needs to wear out in a few weeks then my three-ring setup is going to stay. Hey if I don't shift out of the middle ring, I've got a 1-ring system too eh? The two extra rings and the frt derailer is the price I'll pay. I don't need to look hip.


C'mon Mike. As a huge contributor over at MTBR for what 12 years? I find it hard to believe that you don't understand the concept of 1 by or narrow-wide rings. It was a mistake of monumental proportions for the OP to post this crap here cause the ensuing chaos should have been seen coming.

To those that don't see the benefits or why the rings wear so fast I will try to explain more clearly. The concept and benefits of a single chainring in front for MTB's was the ability to eliminate the front derailleur, left shifter, cable, housing, and a VERY heavy in comparison triple or double paired to a boat anchor crank and spider. Before one by specific stuff came out.....Clutch rear derailleurs, one by specific cranks with direct mount chainrings (no spider), guys were taking off the big and little rings of their cranksets, and running downhill bike style chain tensioners to keep the chain from falling off the single ring when riding techy sections. Then came clutch equipped rear derailleurs.....the cage of these derailleurs are kept under heavy tension by a clutch type mechanism to hold the chain taut. This came with the additional benefit of eliminating the chain bouncing off the chainstay of the bike and made the ride almost silent. In an additional effort to maintain strict and confident chain retention and control several companies......Race Face, Wolftooth, etc came out with narrow-wide chainrings. These rings match the profile of a bike chain exactly............ie: one tooth is very wide and square and the next tooth is very thin and narrow. The chain sticks firmly to these rings to aid in chain retention. With the absence of the granny gear these chainrings rarely rose above a 32 and are usually 26-30 depending on the size of the largest cog in back. These rings are often aluminum, and when paired with say a Race Face Next SL crank like pictured below can see weight savings of pounds not grams. Great for cross country guys. At the time (and maybe still) The Race Face Next SL was the lightest Carbon crank being commercially produced. The system works as advertised but comes at the expense of rapid chainring wear. Especially if the chainline of the bike is not carefully adjusted, and the rider uses the big cog often. They are not expensive......30-50 bucks and are easily replaced. The photo below is my bike and shows the one ring system as it is meant to be used. That is a 30 tooth chainring and 11-36 cassette. These rings don't sharkfin or show anything remotely resembling the wear we are all used to seeing on road rings....
Hope this helps.


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## Lombard (May 8, 2014)

ghettocop said:


> C'mon Mike. As a huge contributor over at MTBR for what 12 years? I find it hard to believe that you don't understand the concept of 1 by or narrow-wide rings. It was a mistake of monumental proportions for the OP to post this crap here cause the ensuing chaos should have been seen coming.
> 
> To those that don't see the benefits or why the rings wear so fast I will try to explain more clearly. The concept and benefits of a single chainring in front for MTB's was the ability to eliminate the front derailleur, left shifter, cable, housing, and a VERY heavy in comparison triple or double paired to a boat anchor crank and spider. Before one by specific stuff came out.....Clutch rear derailleurs, one by specific cranks with direct mount chainrings (no spider), guys were taking off the big and little rings of their cranksets, and running downhill bike style chain tensioners to keep the chain from falling off the single ring when riding techy sections. Then came clutch equipped rear derailleurs.....the cage of these derailleurs are kept under heavy tension by a clutch type mechanism to hold the chain taut. This came with the additional benefit of eliminating the chain bouncing off the chainstay of the bike and made the ride almost silent. In an additional effort to maintain strict and confident chain retention and control several companies......Race Face, Wolftooth, etc came out with narrow-wide chainrings. These rings match the profile of a bike chain exactly............ie: one tooth is very wide and square and the next tooth is very thin and narrow. The chain sticks firmly to these rings to aid in chain retention. With the absence of the granny gear these chainrings rarely rose above a 32 and are usually 26-30 depending on the size of the largest cog in back. These rings are often aluminum, and when paired with say a Race Face Next SL crank like pictured below can see weight savings of pounds not grams. Great for cross country guys. At the time (and maybe still) The Race Face Next SL was the lightest Carbon crank being commercially produced. The system works as advertised but comes at the expense of rapid chainring wear. Especially if the chainline of the bike is not carefully adjusted, and the rider uses the big cog often. They are not expensive......30-50 bucks and are easily replaced. The photo below is my bike and shows the one ring system as it is meant to be used. That is a 30 tooth chainring and 11-36 cassette. These rings don't sharkfin or show anything remotely resembling the wear we are all used to seeing on road rings....
> Hope this helps.



OK, point taken....I think. However, given the weight savings of eliminating spiders, 2 rings, front derailleur and front shifter, is it really necessary to make the single ring aluminum when a steel one would certainly last longer and not add a significant amount of weight. Unless you are a racer or an obsessive weight weenie, this should not matter to you.

Call me a fuddy duddy, but I think $30-50 every 400 miles is a bit much to spend on maintenance. I don't know any other part of a bike that wears out in that little mileage. Some people don't even lube their chain that often!


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## Mike T. (Feb 3, 2004)

Lombard said:


> OK, point taken....I think. However, given the weight savings of eliminating spiders, 2 rings, front derailleur and front shifter, is it really necessary to make the single ring aluminum when a steel one would certainly last longer and not add a significant amount of weight. Unless you are a racer or an obsessive weight weenie, this should not matter to you.
> 
> Call me a fuddy duddy, but I think $30-50 every 400 miles is a bit much to spend on maintenance. I don't know any other part of a bike that wears out in that little mileage. Some people don't even lube their chain that often!


To Ghetto, via Lombard's post. As the owner of a sub-20lb MTB I've never bothered about lugging two extra rings and their paraphernalia along. But to me they're not "extra" - they get used. I cruise trails, paved roads & dirt on my 46t big ring, single-track on the middle 34 and climb on the 24. Having just a 32 would not cut it for me but then that's for me an my riding terrain. Others' needs may vary of course.

I'd be pi$$ed if I even went through an *innertube* every x hundred miles, never mind a chainring. Yeah I still use tubes as well as three rings.

I'm a product (decades ago) of the British (road) time-trialing scene and many time-trialers went the single ring route years ago - even some top euro pro riders. Too many unshipped chains had most people reverting back to multiple front rings and front derailers. It's rare to see a single front ring anymore.


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## thisisthebeave (Aug 30, 2015)

Mike T. said:


> I'm not buyin' any of this $hit. If stuff wears out in a few hundred miles (a month?) then it's not viable parts or technology. Conditions my @rse. I raced and trained MTB's for years and didn't wear stuff out like that. So what's the benefit to one chainring? If it needs to wear out in a few weeks then my three-ring setup is going to stay. Hey if I don't shift out of the middle ring, I've got a 1-ring system too eh? The two extra rings and the frt derailer is the price I'll pay. I don't need to look hip.


A 2 hour road bike ride might be 35-45 miles. A 2 hour mtb ride might be 15-20 miles. Mud/water/grit/etc, paired with miles racking up more slowly = wears out in fewer miles than road bikes.


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## Mike T. (Feb 3, 2004)

thisisthebeave said:


> A 2 hour road bike ride might be 35-45 miles. A 2 hour mtb ride might be 15-20 miles. Mud/water/grit/etc, paired with miles racking up more slowly = wears out in fewer miles than road bikes.


I rode/trained/raced MTBs almost exclusively for about 15 years so there isn't much you can tell me about that stuff. Nothing ever wore out in hundreds of miles.


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## thisisthebeave (Aug 30, 2015)

Lombard said:


> OK, point taken....I think. However, given the weight savings of eliminating spiders, 2 rings, front derailleur and front shifter, is it really necessary to make the single ring aluminum when a steel one would certainly last longer and not add a significant amount of weight. Unless you are a racer or an obsessive weight weenie, this should not matter to you.
> 
> Call me a fuddy duddy, but I think $30-50 every 400 miles is a bit much to spend on maintenance. I don't know any other part of a bike that wears out in that little mileage. Some people don't even lube their chain that often!


Everything on a mountain bike wears out faster and requires more maintenance. My road bike with 5,000 miles on it has fewer line items in my maintenance log than my mountain bike with 800 miles AND I track tires for my road bike but not mountain. Rear brake pads, rear tires, suspension service, chainring, chains, etc all last in the 500-1,000 mile realm. Meanwhile I just got 4,616 miles out of my latest road bike tire (3,322 as a front and 1,294 as a rear)!

Anyway, mileage aside I'm just trying to figure out if the skipping is possibly chainring related on my CX bike or if it's another issue. The chain and cassette are pretty new, shift cable and housing is new and it's tuned right, derailleur hangar is straight, no cracked frame or freehub body. I'm running out of things to try.


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## thisisthebeave (Aug 30, 2015)

Mike T. said:


> I rode/trained/raced MTBs almost exclusively for about 15 years so there isn't much you can tell me about that stuff. Nothing ever wore out in hundreds of miles.


My rear brake pads RARELY last beyond 500-600 miles, chains get to .5 stretch in about that time, I rebuild my rear shock every 50 hours of ride time (~500 miles as well), I've burnt up chainrings in less time than that.

I maintain my bike well, keeping it clean, lubing the chain, etc but I'm a heavier rider so stuff like chains and brake pads wear out quicker.

That's all beside the point of the thread though, trying to figure out why my chain is skipping, not what parts should last how long


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## Lombard (May 8, 2014)

thisisthebeave said:


> My rear brake pads RARELY last beyond 500-600 miles, chains get to .5 stretch in about that time, I rebuild my rear shock every 50 hours of ride time (~500 miles as well), I've burnt up chainrings in less time than that.
> 
> I maintain my bike well, keeping it clean, lubing the chain, etc but I'm a heavier rider so stuff like chains and brake pads wear out quicker.
> 
> That's all beside the point of the thread though, trying to figure out why my chain is skipping, not what parts should last how long



Are you sure it's your front that is skipping, not your rear?


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## faulker479 (Jan 12, 2015)

if you have exhausted everything else, just get a new ring and see if that is the issue. Even if it turns out that isn't the problem, wont you need to buy one soon anyway?


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## thisisthebeave (Aug 30, 2015)

Lombard said:


> Are you sure it's your front that is skipping, not your rear?


I'm not certain it's the front, in fact it feels like the rear. I just can't find anything that could be wrong with the rear.

I spend 90% of my time in the 14, 16, 18, and 20 cogs. The 28 that it's slipping in rarely gets used on a pretty new cassette/chain combo as is.


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## duriel (Oct 10, 2013)

Check your limit screw on the RD on the big ring. It may be off just enough when you hit the gas, it looses it.


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## thisisthebeave (Aug 30, 2015)

duriel said:


> Check your limit screw on the RD on the big ring. It may be off just enough when you hit the gas, it looses it.


I thought of this but it does it in the 2nd cog, wouldn't the limit screw not affect it in that gear?


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## duriel (Oct 10, 2013)

Adj the RD with the chain in the 2nd cog. Your RD hanger is bent.


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## thisisthebeave (Aug 30, 2015)

duriel said:


> Adj the RD with the chain in the 2nd cog. Your RD hanger is bent.


Hangar is not bent, checked it with the Park tool.


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## duriel (Oct 10, 2013)

Well, your chainring is not causing skipping in the back. Have we decided that?


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## thisisthebeave (Aug 30, 2015)

duriel said:


> Well, your chainring is not causing skipping in the back. Have we decided that?


I guess... I thought maybe if it was worn it more than the chain it could cause problems on the other end (the cassette) that isn't as worn.


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## duriel (Oct 10, 2013)

OK, then problem solved. It is not the RD, RD hanger, RD limit screws or adj, chain, chain ring, or cassette. You fixed it my friend.


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## Lombard (May 8, 2014)

thisisthebeave said:


> I'm not certain it's the front, in fact it feels like the rear. I just can't find anything that could be wrong with the rear.
> 
> I spend 90% of my time in the 14, 16, 18, and 20 cogs. The 28 that it's slipping in rarely gets used on a pretty new cassette/chain combo as is.




If it feels like it is the rear, I'm pretty sure it is. If the front were indeed slipping, it would have slipped right off the ring by now.

It sounds to me like what you are getting is "ghost shifting" as in your chain is trying to jump to the next larger cog. Try adjusting your rear derailleur barrel 1/4 to 1/2 turn CLOCKWISE and see if this corrects it without affecting your ability to shift to larger cogs.

If this does not solve your problem, your cable may be binding. Many bike makers save a few pennies here and there by installing cheaper galvanized cables rather than the better quality stainless steel cables. Galvanized cables oxidize and become rough which can cause poor shifting. Adding that this is a CX bike has exposed it to moisture, mud and other ills of CX riding and will cause it to oxidize even faster. Don't know which type of cable you have? Run it between your fingers. Does it feel rough? Does it leave a grey residue? If yes, they are galvanized - replace with good quality stainless steel cables!


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## thisisthebeave (Aug 30, 2015)

Lombard said:


> If it feels like it is the rear, I'm pretty sure it is. If the front were indeed slipping, it would have slipped right off the ring by now.
> 
> It sounds to me like what you are getting is "ghost shifting" as in your chain is trying to jump to the next larger cog. Try adjusting your rear derailleur barrel 1/4 to 1/2 turn CLOCKWISE and see if this corrects it without affecting your ability to shift to larger cogs.
> 
> If this does not solve your problem, your cable may be binding. Many bike makers save a few pennies here and there by installing cheaper galvanized cables rather than the better quality stainless steel cables. Galvanized cables oxidize and become rough which can cause poor shifting. Adding that this is a CX bike has exposed it to moisture, mud and other ills of CX riding and will cause it to oxidize even faster. Don't know which type of cable you have? Run it between your fingers. Does it feel rough? Does it leave a grey residue? If yes, they are galvanized - replace with good quality stainless steel cables!


I built the bike from the ground up with the good stuff in Aug 2015. Dura Ace cable and full length internal Jagwire housing, replaced 800 miles ago.


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## Lombard (May 8, 2014)

thisisthebeave said:


> I built the bike from the ground up with the good stuff in Aug 2015. Dura Ace cable and full length internal Jagwire housing, replaced 800 miles ago.


OK, that pretty much eliminates the cable possibility.

Try the 1st thing I suggested:

_It sounds to me like what you are getting is "ghost shifting" as in your chain is trying to jump to the next larger cog. Try adjusting your rear derailleur barrel 1/4 to 1/2 turn CLOCKWISE and see if this corrects it without affecting your ability to shift to larger cogs.

_


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## duriel (Oct 10, 2013)

Why don't you ride it over here and I'll look at it for ya. Or take it to a mechanic.


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