Warning: Aftermarket steel fork failure (from Hawley USA)
http://www.jaysmarine.com/Fork_disaster_1.jpg
The progress of my '78 Guerciotti buildup was slowed (and a goregous Cinelli 1E stem ruined - *crying*) due to the steerer tube splitting on a POS aftermarket fork I was using. Here's the complete post - no sense in wasting space by double-posting it in its entirety: http://www.bikeforums.net/showthread...=1#post4334209 -Kurt |
Those threads run WAY down that fork. Was it hand threaded past the factory threads? That can make one fail.
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Originally Posted by Rev.Chuck
Those threads run WAY down that fork. Was it hand threaded past the factory threads? That can make one fail.
http://www.jaysmarine.com/Fork_disaster_2.jpg Ridiculous. Had I seen it eariler, I would have definitely determined it as being a potential failure zone. Take care, -Kurt |
The fork was the wrong size for the frame. You can't have the wedge in the threaded portion of a fork,
groove or not. I have used this same fork from Hawley and other suppliers with no problem. It comes in different lenths. Yours was to short. I'm starting to see this problem more as threaded forks become scarce. This is a very dangerous goof. Hope you didn't crash. |
Originally Posted by adababy12
The fork was the wrong size for the frame. You can't have the wedge in the threaded portion of a fork,
groove or not. I have used this same fork from Hawley and other suppliers with no problem. It comes in different lenths. Yours was to short. I'm starting to see this problem more as threaded forks become scarce. This is a very dangerous goof. Hope you didn't crash. Take care, -Kurt |
You didn't have to use that fork... ? Unless there's some other reason i'm missing.
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I think Kurt's concern is that if a wedge shouldn't be used on the threaded portion of the steerer (and we seem to all agree on that) then a manufacturer shouldn't sell a fork with threads so far down that no stem could ever reach past the threads.
I sure hope that it was the marketers and not the engineers that decided that threading and notching a steerer that far was a good idea. |
Originally Posted by Little Darwin
I think Kurt's concern is that if a wedge shouldn't be used on the threaded portion of the steerer (and we seem to all agree on that) then a manufacturer shouldn't sell a fork with threads so far down that no stem could ever reach past the threads.
I sure hope that it was the marketers and not the engineers that decided that threading and notching a steerer that far was a good idea. |
Originally Posted by operator
You didn't have to use that fork... ? Unless there's some other reason i'm missing.
Better yet, a Guerciotti fork with the same specifications. -Kurt |
Originally Posted by Little Darwin
I think Kurt's concern is that if a wedge shouldn't be used on the threaded portion of the steerer (and we seem to all agree on that) then a manufacturer shouldn't sell a fork with threads so far down that no stem could ever reach past the threads.
I sure hope that it was the marketers and not the engineers that decided that threading and notching a steerer that far was a good idea. Incedentally, there ARE two steerer lengths available to Hawley's FORK 1133, I've found. One is 250mm, the other 100mm. I needed 222mm of steerer. Guess which one I picked! I ask those who say a stem must be inserted below the threaded section to explain how that is to be achieved on the following forks, if cut down minimally (which will be the case for many frames): http://i2.ebayimg.com/03/i/000/78/43/89cb_1_b.JPG http://www.bonthronebikes.co.uk/img/M/471259.jpg There are others out there - just can't find photos of them at the moment. Take care, -Kurt |
And a photo of the same fork that failed on me - same steerer length too.
Don't tell me that the vast excess of threads on top are there to be specifically to be whacked off to the last two inches during fitting...and that the remainder is just for looks. http://www.swinnertoncycles.co.uk/im...her06/FF05.jpg -Kurt |
common sense and patience goes a long ways. If you're building a classic take the time to find the right fork.
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Originally Posted by cudak888
And a photo of the same fork that failed on me - same steerer length too.
Don't tell me that the vast excess of threads on top are there to be specifically to be whacked off to the last two inches during fitting...and that the remainder is just for looks. Additionally, you never ever want the groove for the keyed washer. Besides the strength issue, they key in the washer will actually bind and hang up on the edge of the groove and prevent you from properly tightening down the locknut. So even with a grooved fork, always use a round washer and use two headset wrenches. Unscrew the adjustable cup UP into the locknut that you're turning DOWN. And using a stem with a diagonal wedge results in much better grip for any given bolt-tension compared to the expander types. The smooth finish on those require an awful lot of force to keep the bars from rotating and can result in broken forks like you've experienced. |
Quit dicking around and get one built...
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Originally Posted by humble_biker
common sense and patience goes a long ways. If you're building a classic take the time to find the right fork.
Originally Posted by DannoXYZ
You have to distinguish that there's a difference between optimum design/engineering vs. convenience.
Originally Posted by DannoXYZ
There are many suppliers that stock chromed steel forks with sloping/lugged crown in a variety of steerer lengths. It's often the retailer that messes up by buying and stocking just one fork with a super-long steerer and then threading it way down.
For the record, the retailer had nothing to do with the threading of this fork. Hawley USA supplies the 250mm variant threaded as shown in the last photo above - with at least 5-6" of threading.
Originally Posted by DannoXYZ
Additionally, you never ever want the groove for the keyed washer. Besides the strength issue, they key in the washer will actually bind and hang up on the edge of the groove and prevent you from properly tightening down the locknut. So even with a grooved fork, always use a round washer and use two headset wrenches. Unscrew the adjustable cup UP into the locknut that you're turning DOWN.
Originally Posted by DannoXYZ
And using a stem with a diagonal wedge results in much better grip for any given bolt-tension compared to the expander types. The smooth finish on those require an awful lot of force to keep the bars from rotating and can result in broken forks like you've experienced.
-Kurt |
Originally Posted by damocles1
Quit dicking around and get one built...
-Kurt |
Originally Posted by cudak888
It is easy to be smart and say that. Try saying that after searching 6+ months for said fork.
Kurt You're a wee bit too confrontational for me Kurt. Good luck to you. |
Originally Posted by humble_biker
Okay here goes pay close attention: Be patient and use the right fork when it comes along.
You're a wee bit too confrontational for me Kurt. Good luck to you. Thanks for the well wishes on finding the fork - keep your fingers crossed for me. Take care, -Kurt |
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