Tandem Cycling - Pictures of bent fork, is this fixable?

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Got home from our ride tonight with the tandem on the roof and attempted to back into my car port. Totally forgetting about the bike on the roof. Stupid, Stupid!
Can this be fixed? Not the way I wanted to celebrate my birthday :(

I could be wrong, but it looks to me like the steerer got bent. I'd say you will need a new fork, though there may be the possibility of replacing the steerer.

As mentioned, looks like the steerer tube got bent. I doubt anyone would even try to fix it. Might be a time to coincide getting a carbon fork, if that is something you were considering.

PK

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Well I took off the fork and I don't know if you can see from the new photos it looks like the tube has been yacked back for lack of a better description. Could the tube be pushed back down flush with the fork?
If it's a no fix what carbon fork would you recommend?

I wouldn't mess with fixing a fork on any bike, let alone a tandem. It's just not worth it. The carbon fork market has been pretty fluid so I'll let others who are more up on it to comment on new carbon forks.

Can this be fixed? Not the way I wanted to celebrate my birthday :(

Sorry to hear dude. I would point out that even if you could "fix it", it is made of Aluminum, so it's probably reached it's fatigue life. I'd think it would be simply safer for you to buy a new fork.

trash it.

You need a new fork...

Going to a composite fork... just a few options and, even if you want to keep your front disc, they're not direct replacements.

All of them use shorter fork legs with less rake so there would be a trade-off / change in how your tandem handles as well as a drop in the front bottom bracket / cornering clearance.

As to whether or not that change would be for the better or worse, that would depend on your post-change impressions / preferences.

Sorry to hear about your fork. I have avoided a roof rack because I know that I would make the same mistake the OP did. Luckily forks are fairly easy to replace. I have heard of ruined frames and car racks ripped off.


See thread on Enve carbon fork for more info. Scroll down to read TandemGeek's post.
http://www.bikeforums.net/showthread.php/842902-Rake-for-an-ENVE-fork


As for a carbon fork I would check on the availability of a old style Wound Up brand fork. Race height 387 is about as high as any carbon fork. Some tandem specialty dealers may have on in stock.
http://www.woundupcomposites.com/specs.html

Thank you guys for your opinions and information. This is our first tandem purchased in April of this year. This is the only "handling" I know. We have just shy of 1000 miles on it and we both feel quite comfortable on it. Don't know if I would like twitchier handling. So assuming there is not a direct carbon replacement for a Cannondale I would still like to keep the front disc brake. Would there need to be much modification to keep the Avid brakes? Also what would be my chances of getting an exact replacement, original fatty?

We have a three day ride coming up at the end of September and really don't want to miss it. We had an over night ride scheduled for tomorrow but that won't happen.

Contact Cannondale or Mel at Tandems East re: Direct Replacement. Note that Mel is at the Midwest Tandem Rally this weekend thru Tues and may not be immediate in reply.

Ouch, that hurts to see. But it sounds like you have a bunch of good avice in the above posts. Good luck.

If the future, you might want to try what I do. As I back the car out of the garage to put the bikes up top, I place two bright orange cones in the garage just inside the door. When I come home, I'd have to run them over to get in and it's an instant reminder. Just don't ask me why I started doing this. It's a sad story.

If you have no luck locating a replacement, any experienced custom frame builder can make a fork for you with the same rake and length as your current fork, though probably not the proprietary Cannondale materials.
Brent

I figured I would wait for Mel From Tandems East to get back from the tandem rally to get his advice. In the mean time I called a local Cannondale dealer to inquire about a replacement fork. I was told that if my steerer tube was bent then my frame was also bent. I have looked it over and seen no other signs of damage but admittedly I'm no expert.
As I was backing into the carport I first hit the rear trunk rack and also my Thule rack was moved forward about 8 inches so there was some give.

Would I be out of line to throw on a fork from one of my single bikes and just ride it down the street to see if I feel anything funky?

I was told that if my steerer tube was bent then my frame was also bent. I have looked it over and seen no other signs of damage but admittedly I'm no expert.

I'm not an expert either, but from what I'm seeing the damage looks to be confined to the fork; specifically, at the bond joint between the steerer and the fork crown. If there was any damage to the frame it would likely be at the welds that join the frame tubes to the head tube. Look for any cracks in the paint; I'm guessing you won't find any. Again, it appears that the energy from the collision with the garage was consumed by the steerer being pulled out of the crown. It doesn't appear as though the steerer is actually "bent".

I figured I would wait for Mel From Tandems East to get back from the tandem rally to get his advice. In the mean time I called a local Cannondale dealer to inquire about a replacement fork. I was told that if my steerer tube was bent then my frame was also bent. I have looked it over and seen no other signs of damage but admittedly I'm no expert.
As I was backing into the carport I first hit the rear trunk rack and also my Thule rack was moved forward about 8 inches so there was some give.

Would I be out of line to throw on a fork from one of my single bikes and just ride it down the street to see if I feel anything funky?


Here we meet the problem with often heard and read advice to check with your local dealer for advice about damage to a frame/fork after a crash. As someone in a profession that gives advice at the risk of being sued I can hardly blame any dealer for concluding that that frame/fork needs replacing. The dealer in this case is playing it safe and has evaluated the problem without needing to see the frame or the fork.

Even if the dealer gives an honest opinion, the risk is really the owner's and he must decide if he is comfortable riding the bike.

You are correct. I was looking for cracked paint over the entire frame and found none. And yes, the tube appears to be yanked out as is evident by gap at the crown. I wonder how the tube is installed, is it pressed in?
Would you not recommend putting another single bike fork on and test riding?

Here we meet the problem with often heard and read advice to check with your local dealer for advice about damage to a frame/fork after a crash. As someone in a profession that gives advice at the risk of being sued I can hardly blame any dealer for concluding that that frame/fork needs replacing. The dealer in this case is playing it safe and has evaluated the problem without needing to see the frame or the fork.

Even if the dealer gives an honest opinion, the risk is really the owner's and he must decide if he is comfortable riding the bike.

I understand the CYA approach especially in this day and age and I'm taking it with a grain of salt. I want Mel's advice on a possible carbon replacement and availability of parts.

Would you not recommend putting another single bike fork on and test riding?

I personally would give it a try if you're really curious. But, if you haven't ridden your tandem solo, just beware that it'd feel funky with a good frame. And if the temporary fork has a different rake, that'll add to the funkiness too. I'd probably try riding it with the full team just to check it out. Certainly no killer record setting ride, but... :-)

I'd think it'd be visually apparent if the frame were damaged, but I agree, the advice of the LBS is the standard CYA answer.

I bent a fork on my single mountain bike years back. I replaced it with another aluminum non-suspension fork. Eventually I realized I couldn't adjust the headset correctly. Turned out that the lower race didn't sit properly in the lower part of the head tub any more because it had ovalized from the time I bent the fork. I mean, the bore of the head tube ovalized, not the lower bearing race. I had to get a new frame.

But nothing scary ever happened... it was just an annoyance. I'd try getting any old $25 steel fork that fits and carefully try it out around the neighborhood before you spend a lot on a nice fork. Or borrow a buddy's fork just long enough to see if the lower bearing race can shift under weight. I'm just passing on my (bad) experience from what I thought was a simple bent fork, but hopefully tandem frames have beefier head tubes than a single mtb. That mtb frame happened to be a Cannondale, but it was from about 1993. Maybe head tubes were thinner back then. (It was 1-1/4" I believe.) Keeping my fingers crossed for you.

Sorry for your bad luck , we've all done that or something just as silly. Regarding damage to the frame, I don't want to bring you down here, but I would also be very concerned about the the shape of the lower portion of the head tube ....specifically the area where the lower bearing race is seated in the HT. I can't imagine how the amount of force required to bend that heavy duty fork would not transfer some of that force to the relatively thin walled head tube without tweaking it. Hopefully I'm wrong... Your idea of installing another fork of any kind should quickly show if that lower race was seriously bent out of alignment Good luck.

Bill J.

well I took a carbon fork and lower race from a single bike and installed it on the tandem. Took it outside and put the front tire against a brick wall and with the rear disk brake engaged tried pushing forward. There was no movement at all at the fork and head tube. I only noticed the tire giving somewhat.
I then took it for a ride solo and ran through the gears. Everything felt fine sans the obvious difference in rake.
What is the general opinion of caliper brakes on a Tandem, not that I will use my single bike forks as a permanent solution? Just want to weigh all of my options.

I think it was Zonatandem who said they use a caliper on the front of theirs with no problem.