|
|
|
Thread Tools | Display Modes |
|
#1
|
|||
|
|||
Broken steel road bike fork
So, I've been noticing that the front brakes of my road bike
were acting "grabby" in that the front would shimmy pretty badly just as I'm coming to a stop. The rims felt a little sticky, maybe some Gatorade got on them and it hasn't really rained in a while. I cleaned the wheels last night and rode into work today. It was still bad, but didn't seem as bad. This has been going on for a week, I didn't think anything of it. I decided to not ride after work and just come home, coming down the driveway, the grabby-ness was really pronounced, so I figure that the brake pads must be contaminated with something. When I took the wheel off, my heart skipped a beat. Without much effort, this is the result: http://www.bitrealm.com/misc/fork/p1000783.jpg http://www.bitrealm.com/misc/fork/p1000784.jpg http://www.bitrealm.com/misc/fork/p1000785.jpg It was hanging by no more than 2mm of steeel. I shudder when I think of the roads I was about to go on, including one really bad bump at the bottom. I don't think it would have held together and when you lose the front like this, it's going to be bad. The shimmy was the wheel moving back and forth due to the fork leg being fatigued. There hasn't been any accident damage since I put this fork on the bike. The crack was almost all the way through, starting from the BACK of the fork leg. |
#2
|
|||
|
|||
Broken steel road bike fork
On Sep 28, 9:37*pm, wrote:
So, I've been noticing that the front brakes of my road bike were acting "grabby" in that the front would shimmy pretty badly just as I'm coming to a stop. *The rims felt a little sticky, maybe some Gatorade got on them and it hasn't really rained in a while. *I cleaned the wheels last night and rode into work today. *It was still bad, but didn't seem as bad. This has been going on for a week, I didn't think anything of it. *I decided to not ride after work and just come home, coming down the driveway, the grabby-ness was really pronounced, so I figure that the brake pads must be contaminated with something. When I took the wheel off, my heart skipped a beat. *Without much effort, this is the result: http://www.bitrealm.com/misc/fork/p1...k/p1000785.jpg It was hanging by no more than 2mm of steeel. *I shudder when I think of the roads I was about to go on, including one really bad bump at the bottom. *I don't think it would have held together and when you lose the front like this, it's going to be bad. The shimmy was the wheel moving back and forth due to the fork leg being fatigued. *There hasn't been any accident damage since I put this fork on the bike. *The crack was almost all the way through, starting from the BACK of the fork leg. Yikes. Congrats on catching that before disaster struck. |
#3
|
|||
|
|||
Broken steel road bike fork
On Sep 28, 10:37*pm, wrote:
So, I've been noticing that the front brakes of my road bike were acting "grabby" in that the front would shimmy pretty badly just as I'm coming to a stop. *The rims felt a little sticky, maybe some Gatorade got on them and it hasn't really rained in a while. *I cleaned the wheels last night and rode into work today. *It was still bad, but didn't seem as bad. This has been going on for a week, I didn't think anything of it. *I decided to not ride after work and just come home, coming down the driveway, the grabby-ness was really pronounced, so I figure that the brake pads must be contaminated with something. When I took the wheel off, my heart skipped a beat. *Without much effort, this is the result: http://www.bitrealm.com/misc/fork/p1...k/p1000785.jpg It was hanging by no more than 2mm of steeel. *I shudder when I think of the roads I was about to go on, including one really bad bump at the bottom. *I don't think it would have held together and when you lose the front like this, it's going to be bad. The shimmy was the wheel moving back and forth due to the fork leg being fatigued. *There hasn't been any accident damage since I put this fork on the bike. *The crack was almost all the way through, starting from the BACK of the fork leg. You might invest in at least one lottery ticket about now. You know, before it all wears off. |
#5
|
|||
|
|||
Broken steel road bike fork
On Sep 29, 5:42*am, jim beam wrote:
On 09/28/2009 09:37 PM, wrote: So, I've been noticing that the front brakes of my road bike were acting "grabby" in that the front would shimmy pretty badly just as I'm coming to a stop. *The rims felt a little sticky, maybe some Gatorade got on them and it hasn't really rained in a while. *I cleaned the wheels last night and rode into work today. *It was still bad, but didn't seem as bad. This has been going on for a week, I didn't think anything of it. *I decided to not ride after work and just come home, coming down the driveway, the grabby-ness was really pronounced, so I figure that the brake pads must be contaminated with something. When I took the wheel off, my heart skipped a beat. *Without much effort, this is the result: http://www.bitrealm.com/misc/fork/p1000783.jpg http://www.bitrealm.com/misc/fork/p1000784.jpg http://www.bitrealm.com/misc/fork/p1000785.jpg It was hanging by no more than 2mm of steeel. *I shudder when I think of the roads I was about to go on, including one really bad bump at the bottom. *I don't think it would have held together and when you lose the front like this, it's going to be bad. The shimmy was the wheel moving back and forth due to the fork leg being fatigued. *There hasn't been any accident damage since I put this fork on the bike. *The crack was almost all the way through, starting from the BACK of the fork leg. chrome plate is bad for fatigue - it contains many fatigue initiators. for the future, consider quality cfrp - unless abused, it's pretty much "fatigue proof". This fork was on the bike for about 8 years and had probably around 12K miles on it in that time. I would like to find a 1" threaded replacement that has eyelets for fenders, but they seem pretty thin on the ground. I can find the exact same fork shown here (in black) that I could still buy. It was a 200 mm steerer tube with 35mm of threading. Cut, it is 190mm with 25mm of threading. The one shown here was made for 27" wheels and I just run long reach calipers. I had to have the crown race cut from 27 to 26.4mm. If not, any 1" threadless forks with eyelets and room for fenders? Anyone, Bueller? |
#6
|
|||
|
|||
Broken steel road bike fork
In article
, wrote: On Sep 29, 5:42*am, jim beam wrote: On 09/28/2009 09:37 PM, wrote: So, I've been noticing that the front brakes of my road bike were acting "grabby" in that the front would shimmy pretty badly just as I'm coming to a stop. *The rims felt a little sticky, maybe some Gatorade got on them and it hasn't really rained in a while. *I cleaned the wheels last night and rode into work today. *It was still bad, but didn't seem as bad. This has been going on for a week, I didn't think anything of it. *I decided to not ride after work and just come home, coming down the driveway, the grabby-ness was really pronounced, so I figure that the brake pads must be contaminated with something. When I took the wheel off, my heart skipped a beat. *Without much effort, this is the result: http://www.bitrealm.com/misc/fork/p1000783.jpg http://www.bitrealm.com/misc/fork/p1000784.jpg http://www.bitrealm.com/misc/fork/p1000785.jpg It was hanging by no more than 2mm of steeel. *I shudder when I think of the roads I was about to go on, including one really bad bump at the bottom. *I don't think it would have held together and when you lose the front like this, it's going to be bad. The shimmy was the wheel moving back and forth due to the fork leg being fatigued. *There hasn't been any accident damage since I put this fork on the bike. *The crack was almost all the way through, starting from the BACK of the fork leg. The crack initiating in the back of the leg is not unusual. chrome plate is bad for fatigue - it contains many fatigue initiators. Chrome plating *can* result in embrittlement but does not necessarily do so. Millions of bikes and other load bearing appplications are chromed without such failures happening. The reason for the failure seem pretty self-evident in the photo. Note how the crack followed the shore line of the socket so perfectly, and note the relative thicknesses of the metal. Note also the lack on a reinforcement tang on the inside of the fork leg. for the future, consider quality cfrp - unless abused, it's pretty much "fatigue proof". More clueless advice from "jim beam." This fork was on the bike for about 8 years and had probably around 12K miles on it in that time. I would like to find a 1" threaded replacement that has eyelets for fenders, but they seem pretty thin on the ground. I can find the exact same fork shown here (in black) that I could still buy. It was a 200 mm steerer tube with 35mm of threading. Cut, it is 190mm with 25mm of threading. The one shown here was made for 27" wheels and I just run long reach calipers. I had to have the crown race cut from 27 to 26.4mm. If not, any 1" threadless forks with eyelets and room for fenders? Harder to find these days since most aftermarket forks are aluminum or CF, lack eyelets and are for 700C wheels (if the bike was made for 27" wheels, going to a 700C fork will affect the geometry). But I would think that any bike shop with a QBP account could order you a fork to fit. Or you could have one made, but that would be expensive. |
#7
|
|||
|
|||
Broken steel road bike fork
On 29 Sep, 16:29, Tim McNamara wrote:
Chrome plating *can* result in embrittlement but does not necessarily do so. *Millions of bikes and other load bearing appplications are chromed without such failures happening. More likely the cause of embrittlement is what causes it with non- chromed forks. Overbrazed. Current common practice is to use oxy-acetylene torch and spelter wire because it is quicker overall. I suspect the higher temperatures obtainable with oxy-acet ensure a deeper penetration of the spelter, alloying with the steel, causing the embrittlement. In skilled experienced hands, oxy-acet does produce excellent results when there are no distractions. I would certainly favour a builder which had the certification of qualification from a technical college in the use of oxy-acetylene for brazing if I was unable to locate one with historic recommendation. That (college cetificate) does not necessarily qualify him to braze cycle forks. And be careful that builders although say they do the work, leave spotty Nigel to do the preperation. Hearth brazed forks heated with natural gas may also suffer with brass embrittlement due to excessive duration in the flame. Good preparation is the key. No cutting with abrasive grit, only by file, plenty of flux in the joint and the use of granular spelter inside the end of the fork reduce the heat exposure of the steel so keeping the alloying depth to a minimum at the edge of the crown. I think it be the filling from the end of the crown rather the end of the fork to be the killer. Nigel, may of course used carbarundum instead of the file and scraper to prepare the forks and crown and if he's applied a paste flux, how much water? The reason for the failure seem pretty self-evident in the photo. *Note how the crack followed the shore line of the socket so perfectly, and note the relative thicknesses of the metal. *Note also the lack on a reinforcement tang on the inside of the fork leg. Overbrazed. for the future, consider quality cfrp - unless abused, it's pretty much "fatigue proof". More clueless advice from "jim beam." overbrazed. |
#8
|
|||
|
|||
Broken steel road bike fork
On 09/29/2009 08:29 AM, Tim McNamara wrote:
In article , wrote: On Sep 29, 5:42�am, jim wrote: On 09/28/2009 09:37 PM, wrote: So, I've been noticing that the front brakes of my road bike were acting "grabby" in that the front would shimmy pretty badly just as I'm coming to a stop. �The rims felt a little sticky, maybe some Gatorade got on them and it hasn't really rained in a while. �I cleaned the wheels last night and rode into work today. �It was still bad, but didn't seem as bad. This has been going on for a week, I didn't think anything of it. �I decided to not ride after work and just come home, coming down the driveway, the grabby-ness was really pronounced, so I figure that the brake pads must be contaminated with something. When I took the wheel off, my heart skipped a beat. �Without much effort, this is the result: http://www.bitrealm.com/misc/fork/p1000783.jpg http://www.bitrealm.com/misc/fork/p1000784.jpg http://www.bitrealm.com/misc/fork/p1000785.jpg It was hanging by no more than 2mm of steeel. �I shudder when I think of the roads I was about to go on, including one really bad bump at the bottom. �I don't think it would have held together and when you lose the front like this, it's going to be bad. The shimmy was the wheel moving back and forth due to the fork leg being fatigued. �There hasn't been any accident damage since I put this fork on the bike. �The crack was almost all the way through, starting from the BACK of the fork leg. The crack initiating in the back of the leg is not unusual. chrome plate is bad for fatigue - it contains many fatigue initiators. Chrome plating *can* result in embrittlement but does not necessarily do so. Millions of bikes and other load bearing appplications are chromed without such failures happening. The reason for the failure seem pretty self-evident in the photo. Note how the crack followed the shore line of the socket so perfectly, and note the relative thicknesses of the metal. Note also the lack on a reinforcement tang on the inside of the fork leg. oh, timmy the retard is now a fatigue expert!!! tell us timmy, which end of the microscope did you cram up your ass when you learned all this bull****? for the future, consider quality cfrp - unless abused, it's pretty much "fatigue proof". More clueless advice from "jim beam." which is the larger force timmy - 1600N or 5000N? This fork was on the bike for about 8 years and had probably around 12K miles on it in that time. I would like to find a 1" threaded replacement that has eyelets for fenders, but they seem pretty thin on the ground. I can find the exact same fork shown here (in black) that I could still buy. It was a 200 mm steerer tube with 35mm of threading. Cut, it is 190mm with 25mm of threading. The one shown here was made for 27" wheels and I just run long reach calipers. I had to have the crown race cut from 27 to 26.4mm. If not, any 1" threadless forks with eyelets and room for fenders? Harder to find these days since most aftermarket forks are aluminum or CF, lack eyelets and are for 700C wheels (if the bike was made for 27" wheels, going to a 700C fork will affect the geometry). But I would think that any bike shop with a QBP account could order you a fork to fit. Or you could have one made, but that would be expensive. what ridiculous retardation. |
#9
|
|||
|
|||
Broken steel road bike fork
On 09/29/2009 02:16 PM, Still Just Me! wrote:
On Tue, 29 Sep 2009 05:42:51 -0700, jim wrote: for the future, consider quality cfrp - unless abused, it's pretty much "fatigue proof". The fact that it was steel and demonstrated fatigue instead of just failing catastrophically (like crappy fiber does when it fails) is the only thing that saved him. er, so a failure is better than a non-failure??? because you're confused between fatigue and over-load or abuse??? jeepers dude, you're winning that stupidity contest again! As always, your advice is useless. no, i cast pearls before ignorant incapable swine. |
#10
|
|||
|
|||
Broken steel road bike fork
|
|
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
WTB: 1" Threaded Steel Road fork | [email protected] | Marketplace | 4 | March 20th 06 07:57 PM |
WTB: Steel Road Fork 700C Straight Legs | [email protected] | Techniques | 0 | May 27th 05 03:11 PM |
WTB: Steel road fork 1" | [email protected] | Marketplace | 5 | May 27th 05 05:19 AM |
WTB Steel Road Fork or WTT Carbon | Phil B. | Marketplace | 2 | April 4th 05 09:57 PM |
Recommendations for a nice steel road fork? | Robert Canon | Marketplace | 4 | February 3rd 04 05:43 PM |