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Cycling induced anoesis
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Discussion Starter · #1 ·
Ever since I picked up my new Tarmac from the LBS there's been a roughness in the drivetrain that starts at the middle 5th or 6th cog, and gets progressively worse up thru the smallest cog. Since it sounded like the large chainring, I replaced it with a spare and, same thing. I've also replaced the chain (105 to Ultegra) and cassette, going from a SRAM 11-28 to a 105 12-25, still no better. BTW, the crankset is a 105 - 39/53 and the problem I'm describing is with the large chainring, so it's not a cross chaining issue. Also, the rear der has been adjusted and tuned. The front der is a non issue, because there's no chain contact contributing to the roughness.

The noise is almost like a groan and you can feel the roughness through the pedals, especially under power, but it's most prevalent on the workstand. Also, the chain bounces as it enters the chainring. That's the best way I can describe it.

I know I can bring the bike back to the LBS and probably start a warranty issue with this, but I've done my own wrenching and would like to at least narrow this down before I bring it in. Any thoughts/ suggestions? Could a bad rear wheel do this?
 

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Cycling induced anoesis
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Discussion Starter · #2 ·
PJ352 said:
Ever since I picked up my new Tarmac from the LBS there's been a roughness in the drivetrain that starts at the middle 5th or 6th cog, and gets progressively worse up thru the smallest cog. Since it sounded like the large chainring, I replaced it with a spare and, same thing. I've also replaced the chain (105 to Ultegra) and cassette, going from a SRAM 11-28 to a 105 12-25, still no better. BTW, the crankset is a 105 - 39/53 and the problem I'm describing is with the large chainring, so it's not a cross chaining issue. Also, the rear der has been adjusted and tuned. The front der is a non issue, because there's no chain contact contributing to the roughness.

The noise is almost like a groan and you can feel the roughness through the pedals, especially under power, but it's most prevalent on the workstand. Also, the chain bounces as it enters the chainring. That's the best way I can describe it.

I know I can bring the bike back to the LBS and probably start a warranty issue with this, but I've done my own wrenching and would like to at least narrow this down before I bring it in. Any thoughts/ suggestions? Could a bad rear wheel do this?
Hey!! Where are all you knowledgeable wrenches out there, out in the garage or down the basements working on your SL2's??!!

C'mon, please share some thoughts, I'm growing old waiting! :eek:
 

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Sounds to me like it could be the lower rear der. stop. Since it is the starting point for the rear der. having it out of whack will hose up all the indexing through the gear range. Upper pulley should line up directly under the smallest ring on the cassette. Might also be worth having the rear der. hanger checked for straightness first. If it's not straight, no amount of der. adjustment is going to help. I'm not aware of any way to check the hanger without the right tools...

just a thought...

later,
simp
 

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Cycling induced anoesis
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Discussion Starter · #4 ·
simplton said:
Sounds to me like it could be the lower rear der. stop. Since it is the starting point for the rear der. having it out of whack will hose up all the indexing through the gear range. Upper pulley should line up directly under the smallest ring on the cassette. Might also be worth having the rear der. hanger checked for straightness first. If it's not straight, no amount of der. adjustment is going to help. I'm not aware of any way to check the hanger without the right tools...

just a thought...

later,
simp
Thanks for the thoughts, simp. I should've mentioned that shifting on the bike was always fine, never a problem. And the rear der adjustments you mentioned have all been done. It's not a shifting problem, but rather a roughness (specifically chain bounces up and down just before entering the chainring) - mainly in the outer ring and 5th/ 6th to smallest cogs.

There's another thread going in Components... that some posters are mentioning the need for spacers. I've installed the one that came with the 105 cassette, but am not aware of any others for the OEM wheels (RS-10's), so I don't know if this could be the issue or a contributing factor.

Anyone else with similar issues or experiences?
 

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I've had something similar with my Rival/Roubaix. The next smaller cog of the cassette was rubbing the outside of the chain plate. (say if the chain was on the 15t, the 14t was rubbing the chain) When on the workstand, lightly pulling on the RD cable would eliminate the problem. Tweaked the adjustments to a least annoying setting. Tightening the cable tension made the most difference, if I remember right.
 

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i've been experiencing this a lot lately on various bikes...all with Ultegra/ D/A drivetrains. it's kind of odd. Shimano was only able to tell me to try a different, new chain. That reduced the feedback, but didn't get rid of it. I was then told that it was due to "sharp edges" on the new chain and cassette. Not a great answer, but I had nothing else to tell customers.
 

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Cycling induced anoesis
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Discussion Starter · #7 ·
the Inbred said:
i've been experiencing this a lot lately on various bikes...all with Ultegra/ D/A drivetrains. it's kind of odd. Shimano was only able to tell me to try a different, new chain. That reduced the feedback, but didn't get rid of it. I was then told that it was due to "sharp edges" on the new chain and cassette. Not a great answer, but I had nothing else to tell customers.
Thanks for the replies, folks!!

Inbred - Ironically, I think all new parts exacerbates the problem. What I've noticed is that as the chain comes around the cassette, the rollers are pushed against the front side of the teeth and where the chain enters the chainring, the rollers are against the rear side of the teeth. In essence, when the drivetrain is in motion the chain is pulled taut between the cassette and chainring, creating the roughness. If the parts in question (chain, cassette and chainring) all had some wear (slightly rounded teeth, slightly stretched chain), the tolerances would be lower, creating less chain bounce. Of course, this is all conjecture on my part, because this is a new build with all new parts.
 

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Recently,I rode my Giant w/ Ultegra vis a vis my Specialized Roubaix Expert Rival and I was amazed at the difference in shifting - the Ultegra was like "butttta'" while the Rival was quite functional but not as smooth as the Ultegra!
 

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Cycling induced anoesis
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Discussion Starter · #9 ·
jonpom said:
Recently,I rode my Giant w/ Ultegra vis a vis my Specialized Roubaix Expert Rival and I was amazed at the difference in shifting - the Ultegra was like "butttta'" while the Rival was quite functional but not as smooth as the Ultegra!
Agreed. I've been a Shimano user since the mid 80's and have no qualms with their components. Again, I'm not experiencing shifting problems, just roughness/ noise in the drivetrain. Narrowing down the source is similar to trying to pin down the source of squeaks on bikes.They seem to come from everywhere.

The possibility still exists that it's the rear wheel - specifically the freewheel, but that's a guess like all my previous ones. I may have to buy a second bike so I'll have spare parts to swap! :)
 

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Cycling induced anoesis
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Discussion Starter · #11 ·
russotto said:
Is it possible the wheel isn't seated quite right (or the frame is defective) and the cassette is slightly canted with respect to the chainrings?
Thanks for the thoughts. I've had the rear wheel off and on a half dozen times and it sets into the dropouts with nary a problem - centers itself fine in regards to the seat/ chain stays, so (I'm hoping, anyway) it's not the frame. Also, I'd think a problem w/ the frame would result in shifting and/ or tracking issues, and I have none of those. There are decals inside the rear hub and, using them as a point of reference, I did notice that the noise is consistent with the revolutions of the wheel.

I'm leaning towards the problem being with the hub or freewheel or both, but don't have a spare available to prove that theory. For what it's worth, the noise (and vibration) becomes more pronounced in the higher range (smaller) cogs, and outer ring - at speeds approaching and above 30 MPH. Needless to say, I don't reach those speeds often! :)

I may just disassemble, clean and relube the hub and see if that improves things any.
 

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first check your b-screw, the one that is the stop for the rearword swinging action of your derailleur, make sure the teeth on the upper derailleur pulley are not touching the teeth of the cogs through the chain, this causes roughness.

also make sure you have a good chain, don't just think its good because its new, try a different new one.

please please please make sure you have all 10-speed components in your drivetrain, again don't just assume its right, something is wrong

you did the first thing right with switching to the shimano cassette, the stock sram ones have been very rough on all bikes we've put them on at the LBS I work at (about 10 of our personal bikes have all experienced roughness with sram cassettes)

make sure your chain is routed through the derailleur right, it might be brushing over one of the guards where it goes over the small pulleys (i have done this and it does not make as much noise as you'd think since the chain is in very little tension at the derailleur)

clean and lube your chain, you'd be surprised.

have your derailleur hanger checked with a straightening tool, watch them do this by actually removing the derailleur and screwing the tool with the swingy arm in, and make sure they use the same spot on the rim as they rotate both the tool and the tire around, lets not go assuming your wheels are perfectly true now... (common mistake that causes mis-adjustments of derailleur hangers)

finally make sure you're not being a hypercritical weirdo and getting upset becuase your little bikey is making noise when you go beside a concrete wall, it might just sound like a bike.

post-finally remember that you have the lowest quality 10-speed groupo available from the biggest parts manufacturer, I've seen lots of and put thousands of miles on 10-speed 105 components and seen lots of and ridden thousands of miles on dura-ace 10-speed components and there is a reason the 105 bike costs $1800 and the dura-ace bike costs $6100. remember there has to be something to gain by spending 3 times the money and that doesn't mean there has to be something wrong with the cheap stuff if its not working perfectly, thats what the expensive stuff is for.
please know 105 10-speed holds a place in my heart and I would never dog on it, but lets be real.
 

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Cycling induced anoesis
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Discussion Starter · #13 ·
mikbowyer said:
first check your b-screw, the one that is the stop for the rearword swinging action of your derailleur, make sure the teeth on the upper derailleur pulley are not touching the teeth of the cogs through the chain, this causes roughness.

also make sure you have a good chain, don't just think its good because its new, try a different new one.

please please please make sure you have all 10-speed components in your drivetrain, again don't just assume its right, something is wrong

you did the first thing right with switching to the shimano cassette, the stock sram ones have been very rough on all bikes we've put them on at the LBS I work at (about 10 of our personal bikes have all experienced roughness with sram cassettes)

make sure your chain is routed through the derailleur right, it might be brushing over one of the guards where it goes over the small pulleys (i have done this and it does not make as much noise as you'd think since the chain is in very little tension at the derailleur)

clean and lube your chain, you'd be surprised.

have your derailleur hanger checked with a straightening tool, watch them do this by actually removing the derailleur and screwing the tool with the swingy arm in, and make sure they use the same spot on the rim as they rotate both the tool and the tire around, lets not go assuming your wheels are perfectly true now... (common mistake that causes mis-adjustments of derailleur hangers)

finally make sure you're not being a hypercritical weirdo and getting upset becuase your little bikey is making noise when you go beside a concrete wall, it might just sound like a bike.

post-finally remember that you have the lowest quality 10-speed groupo available from the biggest parts manufacturer, I've seen lots of and put thousands of miles on 10-speed 105 components and seen lots of and ridden thousands of miles on dura-ace 10-speed components and there is a reason the 105 bike costs $1800 and the dura-ace bike costs $6100. remember there has to be something to gain by spending 3 times the money and that doesn't mean there has to be something wrong with the cheap stuff if its not working perfectly, thats what the expensive stuff is for.
please know 105 10-speed holds a place in my heart and I would never dog on it, but lets be real.
Hey there, Mik. Thanks a lot for taking the time to respond, I appreciate it!!

I'll try and go through the points you touched on to give you an idea of where I'm at with this and maybe you could give me your thoughts from there - or anyone else who chooses to!!

Just so you know, I've done all my own wrenching since the mid-80's, so I'm fairly adept at this bike maintenance thing. I do however have a slight tendancy to expect near perfection from my rides, so this bike - well, specifically the drivetrain - isn't up to my standards, yet.

All that said, the b-screw and high/ low adjustments have been checked, rechecked and fine tuned. The 105 chain has been replaced with an Ultegra, routed correctly and lubed (a couple of times). The components have been checked for 10 spd compatability. I have an Ultegra cassette on order, but have not yet tried that upgrade. Since my last post, I've pretty much narrowed this down to either the rear hub/ freewheel and/ or the cassette, but we'll see.

I have sight checked (I know, it's lame) the read der hanger, but don't have the tool and am resisting bringing the bike to my LBS. First, I want to solve this myself, second, I really don't believe this is the problem. Shifting has never been a problem, only roughness/ noise in the drivetrain in the smaller cogs.

Lastly, I agree with your assessment of 105 as opposed to Ultegra and DA. My last bike was a mix of Ult/ DA and ran smooth as silk for the 18 years I rode it. If I had to do it over, I'd have gone one up to the Expert, but being my first CF bike, I wanted to test the waters before plunging in, financially speaking.

I think I've about covered it. Thanks again for your time and input.
 
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