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  #1  
Old June 7th 21, 08:54 PM posted to rec.bicycles.tech
Tom Kunich[_4_]
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I suppose this is directed more at Andrew and maybe Jay.

I just spent 45 minutes replacing a front derailleur shift cable and tuning the front derailleur to operate silently.

How much faster do pro mechanics do to achieve the silent running that usually takes me so long? I say this because one of the largest features of Di2 is that a single rather rough adjustment of the Di2 allows the front and rear derailleurs to run smoothly and silently with fully automatic trimming of front as you shift.

Surely there is a reason that Shimano went to so much trouble to include all of this complexity.
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  #2  
Old June 13th 21, 08:42 PM posted to rec.bicycles.tech
Tom Kunich[_4_]
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Default More Shifting Problems

On Monday, June 7, 2021 at 12:54:25 PM UTC-7, Tom Kunich wrote:
I suppose this is directed more at Andrew and maybe Jay.

I just spent 45 minutes replacing a front derailleur shift cable and tuning the front derailleur to operate silently.

How much faster do pro mechanics do to achieve the silent running that usually takes me so long? I say this because one of the largest features of Di2 is that a single rather rough adjustment of the Di2 allows the front and rear derailleurs to run smoothly and silently with fully automatic trimming of front as you shift.

Surely there is a reason that Shimano went to so much trouble to include all of this complexity.

Back at correcting for the overshifting in the rear deraielleur, I found that the rear limit screw for the largest cog had backed out a LONG WAY. almost a full turn. Correcting this I tried to adjust the shifting again.

What I discovered is that I could not get it to shift correctly across the entire rear cogset. It would shift properly at the top or the bottom but there was always one spot where it would always just one of the cogs in the small ring.

Would anyone have any suggestions as to what would cause this? Would it be a misaligned derailleur hanger (which appears to be OK)? It shifts well in the large ring but I do have a mid length rear arm derailleur. Since low gear is a 28 perhaps the longer arm simply isn't needed and causing the problem?
  #3  
Old June 13th 21, 11:57 PM posted to rec.bicycles.tech
Tom Kunich[_4_]
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Posts: 2,196
Default More Shifting Problems

On Sunday, June 13, 2021 at 12:42:16 PM UTC-7, Tom Kunich wrote:
On Monday, June 7, 2021 at 12:54:25 PM UTC-7, Tom Kunich wrote:
I suppose this is directed more at Andrew and maybe Jay.

I just spent 45 minutes replacing a front derailleur shift cable and tuning the front derailleur to operate silently.

How much faster do pro mechanics do to achieve the silent running that usually takes me so long? I say this because one of the largest features of Di2 is that a single rather rough adjustment of the Di2 allows the front and rear derailleurs to run smoothly and silently with fully automatic trimming of front as you shift.

Surely there is a reason that Shimano went to so much trouble to include all of this complexity.

Back at correcting for the overshifting in the rear deraielleur, I found that the rear limit screw for the largest cog had backed out a LONG WAY. almost a full turn. Correcting this I tried to adjust the shifting again.

What I discovered is that I could not get it to shift correctly across the entire rear cogset. It would shift properly at the top or the bottom but there was always one spot where it would always just one of the cogs in the small ring.

Would anyone have any suggestions as to what would cause this? Would it be a misaligned derailleur hanger (which appears to be OK)? It shifts well in the large ring but I do have a mid length rear arm derailleur. Since low gear is a 28 perhaps the longer arm simply isn't needed and causing the problem?

While out on the ride it occurred to me what this must be. One of the differences between the medium arm Campy derailleur and the short arm is that there is a larger gap between the inside idler pulley and the cassette. So one of the reasons that you don't often get this phantom shifting on a short arm derailleur is that the idler pulley would need a great deal more wear to allow the chain to move back and forth enough that it can misshift.. So I would predict that what I am going to find is a worn idler pulley axle. One of the things that I noticed when I put the chain on was that the top idler pulley is a stock Campy item and they use bushing-type bearings. The accessory types I've been using are ceramic bearing types. Now I don't think that the ceramic bearings are of any important but the roller bearing is. Since I just got back from the ride into a strong head wind in ALL directions (how the hell can that happen?) and 1200 feet of climbing in 27 miles I'm a bit tired and need a shower.

Guess I'll go down and bring the bike into the garage.
  #4  
Old June 14th 21, 04:55 PM posted to rec.bicycles.tech
JBeattie
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Posts: 5,870
Default More Shifting Problems

On Sunday, June 13, 2021 at 3:57:54 PM UTC-7, wrote:
On Sunday, June 13, 2021 at 12:42:16 PM UTC-7, Tom Kunich wrote:
On Monday, June 7, 2021 at 12:54:25 PM UTC-7, Tom Kunich wrote:
I suppose this is directed more at Andrew and maybe Jay.

I just spent 45 minutes replacing a front derailleur shift cable and tuning the front derailleur to operate silently.

How much faster do pro mechanics do to achieve the silent running that usually takes me so long? I say this because one of the largest features of Di2 is that a single rather rough adjustment of the Di2 allows the front and rear derailleurs to run smoothly and silently with fully automatic trimming of front as you shift.

Surely there is a reason that Shimano went to so much trouble to include all of this complexity.

Back at correcting for the overshifting in the rear deraielleur, I found that the rear limit screw for the largest cog had backed out a LONG WAY. almost a full turn. Correcting this I tried to adjust the shifting again.

What I discovered is that I could not get it to shift correctly across the entire rear cogset. It would shift properly at the top or the bottom but there was always one spot where it would always just one of the cogs in the small ring.

Would anyone have any suggestions as to what would cause this? Would it be a misaligned derailleur hanger (which appears to be OK)? It shifts well in the large ring but I do have a mid length rear arm derailleur. Since low gear is a 28 perhaps the longer arm simply isn't needed and causing the problem?

While out on the ride it occurred to me what this must be. One of the differences between the medium arm Campy derailleur and the short arm is that there is a larger gap between the inside idler pulley and the cassette. So one of the reasons that you don't often get this phantom shifting on a short arm derailleur is that the idler pulley would need a great deal more wear to allow the chain to move back and forth enough that it can misshift.. So I would predict that what I am going to find is a worn idler pulley axle. One of the things that I noticed when I put the chain on was that the top idler pulley is a stock Campy item and they use bushing-type bearings. The accessory types I've been using are ceramic bearing types. Now I don't think that the ceramic bearings are of any important but the roller bearing is. Since I just got back from the ride into a strong head wind in ALL directions (how the hell can that happen?) and 1200 feet of climbing in 27 miles I'm a bit tired and need a shower.

Guess I'll go down and bring the bike into the garage.


Your limit screw should not have any effect on the shifting in the middle of the cassette. Your problems sound like cable tension or a bent derailleur hanger or worn cogs in the middle of your cassette. Whether your derailleur pulleys have bearings or bushings isn't going to make any difference, although worn teeth may affect shifting.

-- Jay Beattie.



  #5  
Old June 14th 21, 08:12 PM posted to rec.bicycles.tech
Tom Kunich[_4_]
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Posts: 2,196
Default More Shifting Problems

On Monday, June 14, 2021 at 8:55:36 AM UTC-7, jbeattie wrote:
On Sunday, June 13, 2021 at 3:57:54 PM UTC-7, wrote:
On Sunday, June 13, 2021 at 12:42:16 PM UTC-7, Tom Kunich wrote:
On Monday, June 7, 2021 at 12:54:25 PM UTC-7, Tom Kunich wrote:
I suppose this is directed more at Andrew and maybe Jay.

I just spent 45 minutes replacing a front derailleur shift cable and tuning the front derailleur to operate silently.

How much faster do pro mechanics do to achieve the silent running that usually takes me so long? I say this because one of the largest features of Di2 is that a single rather rough adjustment of the Di2 allows the front and rear derailleurs to run smoothly and silently with fully automatic trimming of front as you shift.

Surely there is a reason that Shimano went to so much trouble to include all of this complexity.
Back at correcting for the overshifting in the rear deraielleur, I found that the rear limit screw for the largest cog had backed out a LONG WAY.. almost a full turn. Correcting this I tried to adjust the shifting again.

What I discovered is that I could not get it to shift correctly across the entire rear cogset. It would shift properly at the top or the bottom but there was always one spot where it would always just one of the cogs in the small ring.

Would anyone have any suggestions as to what would cause this? Would it be a misaligned derailleur hanger (which appears to be OK)? It shifts well in the large ring but I do have a mid length rear arm derailleur. Since low gear is a 28 perhaps the longer arm simply isn't needed and causing the problem?

While out on the ride it occurred to me what this must be. One of the differences between the medium arm Campy derailleur and the short arm is that there is a larger gap between the inside idler pulley and the cassette. So one of the reasons that you don't often get this phantom shifting on a short arm derailleur is that the idler pulley would need a great deal more wear to allow the chain to move back and forth enough that it can misshift.. So I would predict that what I am going to find is a worn idler pulley axle.. One of the things that I noticed when I put the chain on was that the top idler pulley is a stock Campy item and they use bushing-type bearings. The accessory types I've been using are ceramic bearing types. Now I don't think that the ceramic bearings are of any important but the roller bearing is.. Since I just got back from the ride into a strong head wind in ALL directions (how the hell can that happen?) and 1200 feet of climbing in 27 miles I'm a bit tired and need a shower.

Guess I'll go down and bring the bike into the garage.

Your limit screw should not have any effect on the shifting in the middle of the cassette. Your problems sound like cable tension or a bent derailleur hanger or worn cogs in the middle of your cassette. Whether your derailleur pulleys have bearings or bushings isn't going to make any difference, although worn teeth may affect shifting.


Where did I say anything at all about the limit screw having anything to do with anything but to keep a derailleur from overshifting? While out on a ride I overshifted the rear derailleur. I caught it before there was any damage to the wheel but I did not want to overshift again so I readjusted the rear derailleur tension so that it would not overshift. That unfortunately screwed up the shifting so I had to ride in gears that were not effected.

Don't tell me you wouldn't do the same thing if you didn't have a screwdriver of the proper size to reset the limit screw.
  #6  
Old June 15th 21, 03:08 AM posted to rec.bicycles.tech
Frank Krygowski[_4_]
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Default More Shifting Problems

On 6/14/2021 3:12 PM, Tom Kunich wrote:
On Monday, June 14, 2021 at 8:55:36 AM UTC-7, jbeattie wrote:

Your limit screw should not have any effect on the shifting in the middle of the cassette. Your problems sound like cable tension or a bent derailleur hanger or worn cogs in the middle of your cassette. Whether your derailleur pulleys have bearings or bushings isn't going to make any difference, although worn teeth may affect shifting.


Where did I say anything at all about the limit screw having anything to do with anything but to keep a derailleur from overshifting? While out on a ride I overshifted the rear derailleur. I caught it before there was any damage to the wheel but I did not want to overshift again so I readjusted the rear derailleur tension so that it would not overshift. That unfortunately screwed up the shifting so I had to ride in gears that were not effected.

Don't tell me you wouldn't do the same thing if you didn't have a screwdriver of the proper size to reset the limit screw.


Despite your long history of mechanical mishaps, you really went on a
bike ride with no tool capable of adjusting a tiny screw?

Why?? To save weight??


--
- Frank Krygowski
  #7  
Old June 15th 21, 03:42 PM posted to rec.bicycles.tech
Tom Kunich[_4_]
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Posts: 2,196
Default More Shifting Problems

On Monday, June 14, 2021 at 7:08:25 PM UTC-7, Frank Krygowski wrote:
On 6/14/2021 3:12 PM, Tom Kunich wrote:
On Monday, June 14, 2021 at 8:55:36 AM UTC-7, jbeattie wrote:

Your limit screw should not have any effect on the shifting in the middle of the cassette. Your problems sound like cable tension or a bent derailleur hanger or worn cogs in the middle of your cassette. Whether your derailleur pulleys have bearings or bushings isn't going to make any difference, although worn teeth may affect shifting.


Where did I say anything at all about the limit screw having anything to do with anything but to keep a derailleur from overshifting? While out on a ride I overshifted the rear derailleur. I caught it before there was any damage to the wheel but I did not want to overshift again so I readjusted the rear derailleur tension so that it would not overshift. That unfortunately screwed up the shifting so I had to ride in gears that were not effected.

Don't tell me you wouldn't do the same thing if you didn't have a screwdriver of the proper size to reset the limit screw.

Despite your long history of mechanical mishaps, you really went on a
bike ride with no tool capable of adjusting a tiny screw?

Why?? To save weight??


There is a reason that I was successful and you were a nothing that did nothing - I had the sense to know that simply turning an adjustment screw would get me back 10 miles where I could properly adjust things. People like you stop and block roads until cars get tired of your stupid bull****.
  #8  
Old June 15th 21, 04:37 PM posted to rec.bicycles.tech
Frank Krygowski[_4_]
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Posts: 10,538
Default More Shifting Problems

On 6/15/2021 10:42 AM, Tom Kunich wrote:
On Monday, June 14, 2021 at 7:08:25 PM UTC-7, Frank Krygowski wrote:
On 6/14/2021 3:12 PM, Tom Kunich wrote:
On Monday, June 14, 2021 at 8:55:36 AM UTC-7, jbeattie wrote:

Your limit screw should not have any effect on the shifting in the middle of the cassette. Your problems sound like cable tension or a bent derailleur hanger or worn cogs in the middle of your cassette. Whether your derailleur pulleys have bearings or bushings isn't going to make any difference, although worn teeth may affect shifting.

Where did I say anything at all about the limit screw having anything to do with anything but to keep a derailleur from overshifting? While out on a ride I overshifted the rear derailleur. I caught it before there was any damage to the wheel but I did not want to overshift again so I readjusted the rear derailleur tension so that it would not overshift. That unfortunately screwed up the shifting so I had to ride in gears that were not effected.

Don't tell me you wouldn't do the same thing if you didn't have a screwdriver of the proper size to reset the limit screw.

Despite your long history of mechanical mishaps, you really went on a
bike ride with no tool capable of adjusting a tiny screw?

Why?? To save weight??


There is a reason that I was successful and you were a nothing that did nothing - I had the sense to know that simply turning an adjustment screw would get me back 10 miles where I could properly adjust things. People like you stop and block roads until cars get tired of your stupid bull****.


No, people like me turn the proper screw and ride on.

It sounds like you messed with cable length adjustment, screwing up your
shifting, when you should have messed with the limit screw and left your
shift levers in synch with your cog spacing.

Again: You should consider keeping your mistakes secret. You continually
tell us about your incompetence.


--
- Frank Krygowski
  #9  
Old June 15th 21, 06:29 PM posted to rec.bicycles.tech
Lou Holtman[_5_]
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Default More Shifting Problems

On Tuesday, June 15, 2021 at 5:37:08 PM UTC+2, Frank Krygowski wrote:
On 6/15/2021 10:42 AM, Tom Kunich wrote:
On Monday, June 14, 2021 at 7:08:25 PM UTC-7, Frank Krygowski wrote:
On 6/14/2021 3:12 PM, Tom Kunich wrote:
On Monday, June 14, 2021 at 8:55:36 AM UTC-7, jbeattie wrote:

Your limit screw should not have any effect on the shifting in the middle of the cassette. Your problems sound like cable tension or a bent derailleur hanger or worn cogs in the middle of your cassette. Whether your derailleur pulleys have bearings or bushings isn't going to make any difference, although worn teeth may affect shifting.

Where did I say anything at all about the limit screw having anything to do with anything but to keep a derailleur from overshifting? While out on a ride I overshifted the rear derailleur. I caught it before there was any damage to the wheel but I did not want to overshift again so I readjusted the rear derailleur tension so that it would not overshift. That unfortunately screwed up the shifting so I had to ride in gears that were not effected.

Don't tell me you wouldn't do the same thing if you didn't have a screwdriver of the proper size to reset the limit screw.
Despite your long history of mechanical mishaps, you really went on a
bike ride with no tool capable of adjusting a tiny screw?

Why?? To save weight??


There is a reason that I was successful and you were a nothing that did nothing - I had the sense to know that simply turning an adjustment screw would get me back 10 miles where I could properly adjust things. People like you stop and block roads until cars get tired of your stupid bull****.

No, people like me turn the proper screw and ride on.

It sounds like you messed with cable length adjustment, screwing up your
shifting, when you should have messed with the limit screw and left your
shift levers in synch with your cog spacing.

Again: You should consider keeping your mistakes secret. You continually
tell us about your incompetence.


--
- Frank Krygowski



Again limit screws have nothing to do with the adjustment of your RD. I once explained that to a friend with a simple drawing:

https://photos.app.goo.gl/xT6x8vfz4hRwx9Y9A

If the chain is jumping between gears than:
- RD is not adjusted right,
- bent RD hanger,
- upper pulley wheel has to much radial play causing hysteresis which makes adjustment near impossible,
- B screw adjustment way off,
- outer plate of a chain link displaced,
- wrong cassette,
- the overshift feature in the shifter is gummed up and doesn't back up fast enough. I have only experience with Campy 9 and 10 speed shifters with this. I don't know how it works in a 11 and 12 sp shifter.

Adjustment of the limit screws is not in this equation.
A RD in an indexed system should be a matter of 5 minutes.

Lou
  #10  
Old June 15th 21, 07:07 PM posted to rec.bicycles.tech
JBeattie
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Posts: 5,870
Default More Shifting Problems

On Tuesday, June 15, 2021 at 10:30:00 AM UTC-7, wrote:
On Tuesday, June 15, 2021 at 5:37:08 PM UTC+2, Frank Krygowski wrote:
On 6/15/2021 10:42 AM, Tom Kunich wrote:
On Monday, June 14, 2021 at 7:08:25 PM UTC-7, Frank Krygowski wrote:
On 6/14/2021 3:12 PM, Tom Kunich wrote:
On Monday, June 14, 2021 at 8:55:36 AM UTC-7, jbeattie wrote:

Your limit screw should not have any effect on the shifting in the middle of the cassette. Your problems sound like cable tension or a bent derailleur hanger or worn cogs in the middle of your cassette. Whether your derailleur pulleys have bearings or bushings isn't going to make any difference, although worn teeth may affect shifting.

Where did I say anything at all about the limit screw having anything to do with anything but to keep a derailleur from overshifting? While out on a ride I overshifted the rear derailleur. I caught it before there was any damage to the wheel but I did not want to overshift again so I readjusted the rear derailleur tension so that it would not overshift. That unfortunately screwed up the shifting so I had to ride in gears that were not effected.

Don't tell me you wouldn't do the same thing if you didn't have a screwdriver of the proper size to reset the limit screw.
Despite your long history of mechanical mishaps, you really went on a
bike ride with no tool capable of adjusting a tiny screw?

Why?? To save weight??

There is a reason that I was successful and you were a nothing that did nothing - I had the sense to know that simply turning an adjustment screw would get me back 10 miles where I could properly adjust things. People like you stop and block roads until cars get tired of your stupid bull****.

No, people like me turn the proper screw and ride on.

It sounds like you messed with cable length adjustment, screwing up your
shifting, when you should have messed with the limit screw and left your
shift levers in synch with your cog spacing.

Again: You should consider keeping your mistakes secret. You continually
tell us about your incompetence.


--
- Frank Krygowski

Again limit screws have nothing to do with the adjustment of your RD. I once explained that to a friend with a simple drawing:

https://photos.app.goo.gl/xT6x8vfz4hRwx9Y9A

If the chain is jumping between gears than:
- RD is not adjusted right,
- bent RD hanger,
- upper pulley wheel has to much radial play causing hysteresis which makes adjustment near impossible,
- B screw adjustment way off,
- outer plate of a chain link displaced,
- wrong cassette,
- the overshift feature in the shifter is gummed up and doesn't back up fast enough. I have only experience with Campy 9 and 10 speed shifters with this. I don't know how it works in a 11 and 12 sp shifter.

Adjustment of the limit screws is not in this equation.
A RD in an indexed system should be a matter of 5 minutes.


As I understand it, he almost put his chain into the spokes shifting into the big cog. Rather than screwing-in his low gear limit screw (because he didn't have a pocket tool, apparently), he de-tensioned the cable, which (as one would expect) screwed up his shifting.

I think he tried to correct this at home, and it didn't work. It still shifted poorly. If he was putting his derailleur into the spokes, I wouldn't be surprised if he had a bent hanger.

-- Jay Beattie

 




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