Bike Forums

Bike Forums (https://www.bikeforums.net/forum.php)
-   Bicycle Mechanics (https://www.bikeforums.net/bicycle-mechanics/)
-   -   Warning: Aftermarket steel fork failure (from Hawley USA) (https://www.bikeforums.net/bicycle-mechanics/292596-warning-aftermarket-steel-fork-failure-hawley-usa.html)

cudak888 04-28-07 08:22 PM

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

Rev.Chuck 04-28-07 10:21 PM

Those threads run WAY down that fork. Was it hand threaded past the factory threads? That can make one fail.

cudak888 04-28-07 10:41 PM


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.

Factory threads, and a factory groove for the washer. One of those aftermarket replacement forks. Take a look at the thickness of the groove area - where it split - in this photo:

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

adababy12 04-30-07 05:00 PM

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.

cudak888 05-01-07 08:36 AM


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.

Then, may I ask you, why does it come with nearly 5-6" of threading...and in one steerer length only? I'm not too keen on putting the expander in the threaded portion, but in this case, it was nessesary.

Take care,

-Kurt

operator 05-01-07 08:46 AM

You didn't have to use that fork... ? Unless there's some other reason i'm missing.

Little Darwin 05-01-07 09:00 AM

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.

TallRider 05-01-07 09:03 AM


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.

+1...

cudak888 05-01-07 09:42 AM


Originally Posted by operator
You didn't have to use that fork... ? Unless there's some other reason i'm missing.

Good, then find me an all-chrome, 700C, threaded 1" fork with a steerer tube length of no less then 222mm, either English or Italian threading. No unicrowns - only sloping (Cinelli style) or lugged.

Better yet, a Guerciotti fork with the same specifications.

-Kurt

cudak888 05-01-07 10:04 AM


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.

Exactly.

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

cudak888 05-01-07 12:42 PM

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

humble_biker 05-01-07 01:01 PM

common sense and patience goes a long ways. If you're building a classic take the time to find the right fork.

DannoXYZ 05-01-07 01:15 PM


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.

You have to distinguish that there's a difference between optimum design/engineering vs. convenience. From a design perspective, all the previous guys are right in that you shouldn't have any more threads than necessary to adjust & tighten the headset; about 1/2-3/4" is all that's needed. 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.

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.

damocles1 05-01-07 01:53 PM

Quit dicking around and get one built...

cudak888 05-01-07 01:59 PM


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.

It is easy to be smart and say that. Try saying that after searching 6+ months for said fork.



Originally Posted by DannoXYZ
You have to distinguish that there's a difference between optimum design/engineering vs. convenience.

That I understand - but it is inexcusable for the design be manufactured in such a way to immidiately fail, even though the product is designed in such a way as to be used in such a fashion to allow the stem to bind at the threaded area.


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.

Show me others that supply a similar sloping or lugged crown 700C fork with the proper steerer length for my machine - I am ready to purchase one immidiately.

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.

Finally - someone who admits that these washers are useless. You have essentially described how I tighten my headsets. I've had many washers that also wear their own tab away against the sharp threads, and begin to spin around on the steerer. Makes it a PITA to get them off if you ever need to pull the fork though.


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.

Maybe so, but I can guarentee you that I won't use anything other then a Cinelli or ITM stem from the period. Thousands of them held up for racers back in the '70s and '80s (AVA excluded), no reason why they shouldn't hold up today. They may not be as efficent as the wedge stems, but they are sufficent.

-Kurt

cudak888 05-01-07 02:01 PM


Originally Posted by damocles1
Quit dicking around and get one built...

Fine, just send me over the $250 in cash or so, and I'll do so. :p

-Kurt

humble_biker 05-02-07 01:47 PM


Originally Posted by cudak888
It is easy to be smart and say that. Try saying that after searching 6+ months for said fork.
Kurt

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.

cudak888 05-04-07 09:37 AM


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.

Definitely, but one must realize that if after presenting a simple finding, a whole forum seemingly gangs up against you, one does become just a bit defensive :eek:

Thanks for the well wishes on finding the fork - keep your fingers crossed for me.

Take care,

-Kurt


All times are GMT -6. The time now is 04:50 PM.


Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.