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#21
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Knackered bottom bracket.
"AMuzi" wrote in message ... On 8/10/2016 2:45 PM, Ian Field wrote: "John B." wrote in message ... On Tue, 9 Aug 2016 19:30:48 +0100, "Ian Field" wrote: wrote in message ... On Sunday, August 7, 2016 at 2:35:14 PM UTC-7, AMuzi wrote: On 8/7/2016 3:59 PM, Ian Field wrote: Among the bikes I've stripped for salvage recently; there seems to be an increasing number with totally wrecked bottom bracket bearings. Can't ever remember wrecking one myself - even a very old rusty Raleigh. Is quality going downhill just lately? Older (pre-1980s), products which have had no maintenance since new are just about at life's end. Lubricants dessicate and fail, bearings and bearing surfaces shortly after. Just about anything except very top-end models after roughly 1990 were mostly built without significant shop prep as labor costs rose. Most shops quit full all-parts-off new bicycle prep and the factory setup was marginal at best. There are exceptions but that's the general run of it. That said, regular cleaning and lubrication can keep even midrange hub and BB bearings running for a cyclist's lifetime. We see Record hubs regularly (mailed in for new spokes and rims) which are running well after 40~50 years with annual or 2-year bearing service. -- Andrew Muzi www.yellowjersey.org/ Open every day since 1 April, 1971 I've taken apart 10 or 12 year old bike bottom brackets and the grease is black with dirt and wear from rollers running on bare metal. With maintenance old fashioned open roller bottom brackets will last forever. Most of the real old bikes I ended up with probably never got any oil since leaving the shop. Very often rusty, but advanced lubricants hide many sins. Once or twice I've had to adjust bottom bracket bearing on old bikes - but never had to repair a broken one. A relative had a complete BB bearing failure on a very recent bike, the spacer cage had been crushed and the shop didn't have any, so I filled the cup with balls. AFAIK: My brother sold the bike when the relative passed on. If you do that again the old rule of thumb was always one ball less than full. You put balls in the outer race, shoulder to shoulder, as it were until it is full. Then take out one ball and assemble the bearing. Utter bollox as I'd expect from you. Leaving one ball out creates a gap that the cone settles into - then the cone will be resting the entire force on the 2 balls that are either side of the gap. The cup is always designed so too many balls won't fit, and too few will be obvious. For any given standard cup-and-cone design, the correct count minus one will ride at the exact same diameter and run just fine (albeit with faster wear from fewer wear points). Add one more than correct count and balls contact sections of the cup and/or cone the designer never intended. The system will chew itself up in short order. Hence the general rule of thumb to run short when in doubt. You must be working with some very badly designed bearings! All the ones I've seen had a very small clearance when correctly filled. Leaving a ball out creates a gap that the cone deflects into under load - then; only 2 ball bearings are carrying all of the load. It really is that simple!!! |
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#22
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Knackered bottom bracket.
"John B." wrote in message ... On Wed, 10 Aug 2016 20:45:15 +0100, "Ian Field" wrote: "John B." wrote in message . .. On Tue, 9 Aug 2016 19:30:48 +0100, "Ian Field" wrote: wrote in message ... On Sunday, August 7, 2016 at 2:35:14 PM UTC-7, AMuzi wrote: On 8/7/2016 3:59 PM, Ian Field wrote: Among the bikes I've stripped for salvage recently; there seems to be an increasing number with totally wrecked bottom bracket bearings. Can't ever remember wrecking one myself - even a very old rusty Raleigh. Is quality going downhill just lately? Older (pre-1980s), products which have had no maintenance since new are just about at life's end. Lubricants dessicate and fail, bearings and bearing surfaces shortly after. Just about anything except very top-end models after roughly 1990 were mostly built without significant shop prep as labor costs rose. Most shops quit full all-parts-off new bicycle prep and the factory setup was marginal at best. There are exceptions but that's the general run of it. That said, regular cleaning and lubrication can keep even midrange hub and BB bearings running for a cyclist's lifetime. We see Record hubs regularly (mailed in for new spokes and rims) which are running well after 40~50 years with annual or 2-year bearing service. -- Andrew Muzi www.yellowjersey.org/ Open every day since 1 April, 1971 I've taken apart 10 or 12 year old bike bottom brackets and the grease is black with dirt and wear from rollers running on bare metal. With maintenance old fashioned open roller bottom brackets will last forever. Most of the real old bikes I ended up with probably never got any oil since leaving the shop. Very often rusty, but advanced lubricants hide many sins. Once or twice I've had to adjust bottom bracket bearing on old bikes - but never had to repair a broken one. A relative had a complete BB bearing failure on a very recent bike, the spacer cage had been crushed and the shop didn't have any, so I filled the cup with balls. AFAIK: My brother sold the bike when the relative passed on. If you do that again the old rule of thumb was always one ball less than full. You put balls in the outer race, shoulder to shoulder, as it were until it is full. Then take out one ball and assemble the bearing. Utter bollox as I'd expect from you. Leaving one ball out creates a gap that the cone settles into - then the cone will be resting the entire force on the 2 balls that are either side of the gap. The cup is always designed so too many balls won't fit, and too few will be obvious. Yup, Certainly! Of course a great many others don't agree with you. For example: http://www.parktool.com/blog/repair-...icle-section-7 But of course, the fact that probably the largest maker of bike tools in the U.S. doesn't agree with you is no cause for alarm. Oranges to onions - AFAICS: that only describes the caged variety of cone/cup bearing - leaving a ball out of that would still fail in short order. And I'm really puzzled how someone even as thick as you can get confused about how many ball bearings to fit in a caged assembly!!! The fact remains - if you leave a gap in a filled cup; the cone will deflect into the gap and 2 ball bearings will carry the whole load. It really is that simple!!!!! |
#23
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Knackered bottom bracket.
On 8/11/2016 1:13 PM, Ian Field wrote:
"AMuzi" wrote in message ... On 8/10/2016 2:45 PM, Ian Field wrote: "John B." wrote in message ... On Tue, 9 Aug 2016 19:30:48 +0100, "Ian Field" wrote: wrote in message ... On Sunday, August 7, 2016 at 2:35:14 PM UTC-7, AMuzi wrote: On 8/7/2016 3:59 PM, Ian Field wrote: Among the bikes I've stripped for salvage recently; there seems to be an increasing number with totally wrecked bottom bracket bearings. Can't ever remember wrecking one myself - even a very old rusty Raleigh. Is quality going downhill just lately? Older (pre-1980s), products which have had no maintenance since new are just about at life's end. Lubricants dessicate and fail, bearings and bearing surfaces shortly after. Just about anything except very top-end models after roughly 1990 were mostly built without significant shop prep as labor costs rose. Most shops quit full all-parts-off new bicycle prep and the factory setup was marginal at best. There are exceptions but that's the general run of it. That said, regular cleaning and lubrication can keep even midrange hub and BB bearings running for a cyclist's lifetime. We see Record hubs regularly (mailed in for new spokes and rims) which are running well after 40~50 years with annual or 2-year bearing service. -- Andrew Muzi www.yellowjersey.org/ Open every day since 1 April, 1971 I've taken apart 10 or 12 year old bike bottom brackets and the grease is black with dirt and wear from rollers running on bare metal. With maintenance old fashioned open roller bottom brackets will last forever. Most of the real old bikes I ended up with probably never got any oil since leaving the shop. Very often rusty, but advanced lubricants hide many sins. Once or twice I've had to adjust bottom bracket bearing on old bikes - but never had to repair a broken one. A relative had a complete BB bearing failure on a very recent bike, the spacer cage had been crushed and the shop didn't have any, so I filled the cup with balls. AFAIK: My brother sold the bike when the relative passed on. If you do that again the old rule of thumb was always one ball less than full. You put balls in the outer race, shoulder to shoulder, as it were until it is full. Then take out one ball and assemble the bearing. Utter bollox as I'd expect from you. Leaving one ball out creates a gap that the cone settles into - then the cone will be resting the entire force on the 2 balls that are either side of the gap. The cup is always designed so too many balls won't fit, and too few will be obvious. For any given standard cup-and-cone design, the correct count minus one will ride at the exact same diameter and run just fine (albeit with faster wear from fewer wear points). Add one more than correct count and balls contact sections of the cup and/or cone the designer never intended. The system will chew itself up in short order. Hence the general rule of thumb to run short when in doubt. You must be working with some very badly designed bearings! All the ones I've seen had a very small clearance when correctly filled. Leaving a ball out creates a gap that the cone deflects into under load - then; only 2 ball bearings are carrying all of the load. It really is that simple!!! It is simple, but the concept has escaped you. Imagine a cup and cone system (such as a front hub) designed for ten balls but with only nine balls installed. The balls contact the calculated track centered on both cup and cone. Now imagine eleven balls. They cannot contact the center of the curves on cup and cone as one or more will be askew, inherently. -- Andrew Muzi www.yellowjersey.org/ Open every day since 1 April, 1971 |
#24
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Knackered bottom bracket.
"AMuzi" wrote in message ... On 8/11/2016 1:13 PM, Ian Field wrote: "AMuzi" wrote in message ... On 8/10/2016 2:45 PM, Ian Field wrote: "John B." wrote in message ... On Tue, 9 Aug 2016 19:30:48 +0100, "Ian Field" wrote: wrote in message ... On Sunday, August 7, 2016 at 2:35:14 PM UTC-7, AMuzi wrote: On 8/7/2016 3:59 PM, Ian Field wrote: Among the bikes I've stripped for salvage recently; there seems to be an increasing number with totally wrecked bottom bracket bearings. Can't ever remember wrecking one myself - even a very old rusty Raleigh. Is quality going downhill just lately? Older (pre-1980s), products which have had no maintenance since new are just about at life's end. Lubricants dessicate and fail, bearings and bearing surfaces shortly after. Just about anything except very top-end models after roughly 1990 were mostly built without significant shop prep as labor costs rose. Most shops quit full all-parts-off new bicycle prep and the factory setup was marginal at best. There are exceptions but that's the general run of it. That said, regular cleaning and lubrication can keep even midrange hub and BB bearings running for a cyclist's lifetime. We see Record hubs regularly (mailed in for new spokes and rims) which are running well after 40~50 years with annual or 2-year bearing service. -- Andrew Muzi www.yellowjersey.org/ Open every day since 1 April, 1971 I've taken apart 10 or 12 year old bike bottom brackets and the grease is black with dirt and wear from rollers running on bare metal. With maintenance old fashioned open roller bottom brackets will last forever. Most of the real old bikes I ended up with probably never got any oil since leaving the shop. Very often rusty, but advanced lubricants hide many sins. Once or twice I've had to adjust bottom bracket bearing on old bikes - but never had to repair a broken one. A relative had a complete BB bearing failure on a very recent bike, the spacer cage had been crushed and the shop didn't have any, so I filled the cup with balls. AFAIK: My brother sold the bike when the relative passed on. If you do that again the old rule of thumb was always one ball less than full. You put balls in the outer race, shoulder to shoulder, as it were until it is full. Then take out one ball and assemble the bearing. Utter bollox as I'd expect from you. Leaving one ball out creates a gap that the cone settles into - then the cone will be resting the entire force on the 2 balls that are either side of the gap. The cup is always designed so too many balls won't fit, and too few will be obvious. For any given standard cup-and-cone design, the correct count minus one will ride at the exact same diameter and run just fine (albeit with faster wear from fewer wear points). Add one more than correct count and balls contact sections of the cup and/or cone the designer never intended. The system will chew itself up in short order. Hence the general rule of thumb to run short when in doubt. You must be working with some very badly designed bearings! All the ones I've seen had a very small clearance when correctly filled. Leaving a ball out creates a gap that the cone deflects into under load - then; only 2 ball bearings are carrying all of the load. It really is that simple!!! It is simple, but the concept has escaped you. Imagine a cup and cone system (such as a front hub) designed for ten balls but with only nine balls installed. The balls contact the calculated track centered on both cup and cone. Now imagine eleven balls. They cannot contact the center of the curves on cup and cone as one or more will be askew, inherently. You must be working with some very badly designed bearings!!! All I've ever seen have a very small clearance when correctly filled. If you try to cram an extra ball in - it'll be blindingly obvious that the cone doesn't sit right. If you fill the cup, then take out one ball as John.B said - there will be a gap that the cone deflects into under load. That will impose said load on just 2 of all the ball bearings. Still, if you just don't get it - its no surprise that you toddle along behind a ****wit like John.B. |
#25
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Knackered bottom bracket.
On Thursday, August 11, 2016 at 2:13:09 PM UTC-4, Ian Field wrote:
"AMuzi" wrote in message ... On 8/10/2016 2:45 PM, Ian Field wrote: "John B." wrote in message ... On Tue, 9 Aug 2016 19:30:48 +0100, "Ian Field" wrote: wrote in message ... On Sunday, August 7, 2016 at 2:35:14 PM UTC-7, AMuzi wrote: On 8/7/2016 3:59 PM, Ian Field wrote: Among the bikes I've stripped for salvage recently; there seems to be an increasing number with totally wrecked bottom bracket bearings. Can't ever remember wrecking one myself - even a very old rusty Raleigh. Is quality going downhill just lately? Older (pre-1980s), products which have had no maintenance since new are just about at life's end. Lubricants dessicate and fail, bearings and bearing surfaces shortly after. Just about anything except very top-end models after roughly 1990 were mostly built without significant shop prep as labor costs rose. Most shops quit full all-parts-off new bicycle prep and the factory setup was marginal at best. There are exceptions but that's the general run of it. That said, regular cleaning and lubrication can keep even midrange hub and BB bearings running for a cyclist's lifetime. We see Record hubs regularly (mailed in for new spokes and rims) which are running well after 40~50 years with annual or 2-year bearing service. -- Andrew Muzi www.yellowjersey.org/ Open every day since 1 April, 1971 I've taken apart 10 or 12 year old bike bottom brackets and the grease is black with dirt and wear from rollers running on bare metal. With maintenance old fashioned open roller bottom brackets will last forever. Most of the real old bikes I ended up with probably never got any oil since leaving the shop. Very often rusty, but advanced lubricants hide many sins. Once or twice I've had to adjust bottom bracket bearing on old bikes - but never had to repair a broken one. A relative had a complete BB bearing failure on a very recent bike, the spacer cage had been crushed and the shop didn't have any, so I filled the cup with balls. AFAIK: My brother sold the bike when the relative passed on. If you do that again the old rule of thumb was always one ball less than full. You put balls in the outer race, shoulder to shoulder, as it were until it is full. Then take out one ball and assemble the bearing. Utter bollox as I'd expect from you. Leaving one ball out creates a gap that the cone settles into - then the cone will be resting the entire force on the 2 balls that are either side of the gap. The cup is always designed so too many balls won't fit, and too few will be obvious. For any given standard cup-and-cone design, the correct count minus one will ride at the exact same diameter and run just fine (albeit with faster wear from fewer wear points). Add one more than correct count and balls contact sections of the cup and/or cone the designer never intended. The system will chew itself up in short order. Hence the general rule of thumb to run short when in doubt. You must be working with some very badly designed bearings! All the ones I've seen had a very small clearance when correctly filled. Leaving a ball out creates a gap that the cone deflects into under load - then; only 2 ball bearings are carrying all of the load. It really is that simple!!! ask the LBS for a retainer of your cone size n check the spacings ....if you owned a formula car a video is necessary. |
#26
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Knackered bottom bracket.
On 8/12/2016 2:36 PM, Ian Field wrote:
"AMuzi" wrote in message ... On 8/11/2016 1:13 PM, Ian Field wrote: "AMuzi" wrote in message ... On 8/10/2016 2:45 PM, Ian Field wrote: "John B." wrote in message ... On Tue, 9 Aug 2016 19:30:48 +0100, "Ian Field" wrote: wrote in message ... On Sunday, August 7, 2016 at 2:35:14 PM UTC-7, AMuzi wrote: On 8/7/2016 3:59 PM, Ian Field wrote: Among the bikes I've stripped for salvage recently; there seems to be an increasing number with totally wrecked bottom bracket bearings. Can't ever remember wrecking one myself - even a very old rusty Raleigh. Is quality going downhill just lately? Older (pre-1980s), products which have had no maintenance since new are just about at life's end. Lubricants dessicate and fail, bearings and bearing surfaces shortly after. Just about anything except very top-end models after roughly 1990 were mostly built without significant shop prep as labor costs rose. Most shops quit full all-parts-off new bicycle prep and the factory setup was marginal at best. There are exceptions but that's the general run of it. That said, regular cleaning and lubrication can keep even midrange hub and BB bearings running for a cyclist's lifetime. We see Record hubs regularly (mailed in for new spokes and rims) which are running well after 40~50 years with annual or 2-year bearing service. -- Andrew Muzi www.yellowjersey.org/ Open every day since 1 April, 1971 I've taken apart 10 or 12 year old bike bottom brackets and the grease is black with dirt and wear from rollers running on bare metal. With maintenance old fashioned open roller bottom brackets will last forever. Most of the real old bikes I ended up with probably never got any oil since leaving the shop. Very often rusty, but advanced lubricants hide many sins. Once or twice I've had to adjust bottom bracket bearing on old bikes - but never had to repair a broken one. A relative had a complete BB bearing failure on a very recent bike, the spacer cage had been crushed and the shop didn't have any, so I filled the cup with balls. AFAIK: My brother sold the bike when the relative passed on. If you do that again the old rule of thumb was always one ball less than full. You put balls in the outer race, shoulder to shoulder, as it were until it is full. Then take out one ball and assemble the bearing. Utter bollox as I'd expect from you. Leaving one ball out creates a gap that the cone settles into - then the cone will be resting the entire force on the 2 balls that are either side of the gap. The cup is always designed so too many balls won't fit, and too few will be obvious. For any given standard cup-and-cone design, the correct count minus one will ride at the exact same diameter and run just fine (albeit with faster wear from fewer wear points). Add one more than correct count and balls contact sections of the cup and/or cone the designer never intended. The system will chew itself up in short order. Hence the general rule of thumb to run short when in doubt. You must be working with some very badly designed bearings! All the ones I've seen had a very small clearance when correctly filled. Leaving a ball out creates a gap that the cone deflects into under load - then; only 2 ball bearings are carrying all of the load. It really is that simple!!! It is simple, but the concept has escaped you. Imagine a cup and cone system (such as a front hub) designed for ten balls but with only nine balls installed. The balls contact the calculated track centered on both cup and cone. Now imagine eleven balls. They cannot contact the center of the curves on cup and cone as one or more will be askew, inherently. You must be working with some very badly designed bearings!!! All I've ever seen have a very small clearance when correctly filled. If you try to cram an extra ball in - it'll be blindingly obvious that the cone doesn't sit right. If you fill the cup, then take out one ball as John.B said - there will be a gap that the cone deflects into under load. That will impose said load on just 2 of all the ball bearings. Still, if you just don't get it - its no surprise that you toddle along behind a ****wit like John.B. Our loose-ball BB and hub bearings look something like this: http://www.yellowjersey.org/photosfr...ast/bgsect.jpg In our applications, the curve on the cone and cup are larger radius than the ball (which allows some tolerance for misalignment and wear) but the principle is the same in that there is a correct load diameter for the balls. Running short count, such as 9 in place of ten, will run acceptably well at that same diameter[1]. Wear will be proportionally faster but it will not immediately and catastrophically fail. Over count, such as eleven in place of ten, will fail quickly and dramatically as the balls cannot all run at the correct diameter on the actual bearing surfaces. [1] that's for 'short one ball'. Ridiculous examples such as half-count would suffer severe misalignment once all the balls go to one side, which they will. -- Andrew Muzi www.yellowjersey.org/ Open every day since 1 April, 1971 |
#27
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Knackered bottom bracket.
"DATAKOLL MARINE RESEARCH" wrote in message ... On Thursday, August 11, 2016 at 2:13:09 PM UTC-4, Ian Field wrote: "AMuzi" wrote in message ... On 8/10/2016 2:45 PM, Ian Field wrote: "John B." wrote in message ... On Tue, 9 Aug 2016 19:30:48 +0100, "Ian Field" wrote: wrote in message ... On Sunday, August 7, 2016 at 2:35:14 PM UTC-7, AMuzi wrote: On 8/7/2016 3:59 PM, Ian Field wrote: Among the bikes I've stripped for salvage recently; there seems to be an increasing number with totally wrecked bottom bracket bearings. Can't ever remember wrecking one myself - even a very old rusty Raleigh. Is quality going downhill just lately? Older (pre-1980s), products which have had no maintenance since new are just about at life's end. Lubricants dessicate and fail, bearings and bearing surfaces shortly after. Just about anything except very top-end models after roughly 1990 were mostly built without significant shop prep as labor costs rose. Most shops quit full all-parts-off new bicycle prep and the factory setup was marginal at best. There are exceptions but that's the general run of it. That said, regular cleaning and lubrication can keep even midrange hub and BB bearings running for a cyclist's lifetime. We see Record hubs regularly (mailed in for new spokes and rims) which are running well after 40~50 years with annual or 2-year bearing service. -- Andrew Muzi www.yellowjersey.org/ Open every day since 1 April, 1971 I've taken apart 10 or 12 year old bike bottom brackets and the grease is black with dirt and wear from rollers running on bare metal. With maintenance old fashioned open roller bottom brackets will last forever. Most of the real old bikes I ended up with probably never got any oil since leaving the shop. Very often rusty, but advanced lubricants hide many sins. Once or twice I've had to adjust bottom bracket bearing on old bikes - but never had to repair a broken one. A relative had a complete BB bearing failure on a very recent bike, the spacer cage had been crushed and the shop didn't have any, so I filled the cup with balls. AFAIK: My brother sold the bike when the relative passed on. If you do that again the old rule of thumb was always one ball less than full. You put balls in the outer race, shoulder to shoulder, as it were until it is full. Then take out one ball and assemble the bearing. Utter bollox as I'd expect from you. Leaving one ball out creates a gap that the cone settles into - then the cone will be resting the entire force on the 2 balls that are either side of the gap. The cup is always designed so too many balls won't fit, and too few will be obvious. For any given standard cup-and-cone design, the correct count minus one will ride at the exact same diameter and run just fine (albeit with faster wear from fewer wear points). Add one more than correct count and balls contact sections of the cup and/or cone the designer never intended. The system will chew itself up in short order. Hence the general rule of thumb to run short when in doubt. You must be working with some very badly designed bearings! All the ones I've seen had a very small clearance when correctly filled. Leaving a ball out creates a gap that the cone deflects into under load - then; only 2 ball bearings are carrying all of the load. It really is that simple!!! ask the LBS for a retainer of your cone size n check the spacings ....if you owned a formula car a video is necessary. If I was a bearing designer - I probably wouldn't have suggested using retainer/spacers. The higher failure rate compared to filled cup bearings speaks for itself. Having said that - most 2-stroke conrod bearings are caged needle roller bearings. But I think the load bearing properties of needle rollers are a whole 'nother story. |
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