Bent frame.... any hope?
 

I have a very nice Raleigh aluminum frame that I would love to start building, but I need to know if I'm wasting my time. One of the rear stays is slightly bent, starting about 1in below where the brake attaches. It's barely enough to see with the naked eye but it's about 1/2 inch too narrow to mount a wheel.

What I'd like to know is.... how much am I risking the integrity of the frame to bend it back, and are there any good methods to do this? It's a super light frame and doesn't even have any scratches on it, would make a sweet bike but I don't want the stay just to break off or something... any advice? Thanks!

If it was a steel or Ti frame, the answer would be clear that realigning it is possible and worth the trouble.

For an Al frame, particularly a very light one, I'd be hesitant to straighten it. Aluminum tends to fail rather suddenly and doesn't take to bending and rebending very well. I assume if the seatstay is bent, the chainstay is too and realigning the stays would require some real effort.

Short answer; kiss it goodby.

If it's a Raleigh Technium, then it would have steel stays. What model is it? Even with the steel stays I would be a bit leery. A 1/2" movement is ALOT. There's likely more unseen damage/misalignment. If it's all aluminum, then +1 what HillRider said.

Technium
 

The frame is a Raleigh Technium... so does that mean it has steel stays?

Probably so but, IIRC, these were bonded frames with the steel rear stays "glued" into lugs on the aluminum front triangle. That would make the force needed to straighten the stays even more likely to cause other serious problems.

Agreed. I used to own one. That's why I said I'd be very leery of re-aligning it. An impact of enough force to collapse the rear triangle 1/2" is likely going to cause other issues as well. As is the re-alignment. The Techniums were not known for their rigidity anyhow. You're talking about a roughly 20 y.o. frame now. The glue joint could have easily been compromised.
I'm not saying it couldn't be done, but it would never be a frame I'd trust.

thanks
 

Was hoping I could use it to race, but I wouldn't want to ride very fast on a frame I don't trust... oh well, thanks for the feedback though!

Take a magnet to the rear stays to ensure they're steel. If so, I'd try to bend it back without putting to much tension on the joints. Worth a try. If it seems questionable/disaligned/creaky after that, put a basket for trips to the grocery store.

Pictures are worth a 1000 words

I know this thread is old but I still have the frame. And sorry for crappy phone pics, I'll try and borrow someone's actual camera. The first pic shows the bend on the right stay about a half http://bikeforums.net/attachment.php...hmentid=156286http://bikeforums.net/attachment.php...hmentid=156287inch below where the brake would attach. The second pic shows that the stays are too close to fit a wheel. When the axle is in the left dropout, the right dropout is on the second smallest gear of the cassette. Other than the bend, the frame is in almost immaculate shape. Barely even a ding at all! So is it possible to fix this? How would I go about it besides just pulling at it with my hands?

It would likely take more than your hands. And you'd want to use something more focused to ensure it bends only where you want it to bend in any event.

An excellent way to make up clamping pads to support and lever on the tubing with is to drill very slightly undersized holes through some wood and then saw down through the hole along the grain so that you split the hole. The two sides of these clamping forms, or cauls, are then clamped securely to the tubing and then you can apply pressure to straighten the stays. The wood will ensure that there's no harsh point loads and with a bit of time, thought and elbow grease you should be able to straighten the stays out nicely. The good part is that because you're clamping the tubing right next to the bent area you're not going to put any bending stresses onto any of the bonded joints. So assuming the stays are steel (tested with that trusty magnet) then straightening the stays so that the frame is useable should not be all that hard to do. Just go slow and think it all through. You may also need to buy a couple of specific sized drill bits to produce the accuracy of the holes needed to ensure that you support the tubes well. A hair undersize, like by a1/64'th or less and let the wood "bruise" out to an ideal all around fit during the clamping is much better than going over size and having the clamping cuals put more pressure on only the clamping axis. If the fit does end up a hair loose despite your efforts a slip of business card or file folder card stock can be used to shim to an ideal push fit to get the cauls to properly support the tube.

From there build it up and ride it a lot for local short rides for errands. If you don't notice any issues with the bonded joints or other frame related catastrophes start riding it a bit faster and harder along with regular inspections. If it's passing all those tests then do some longer and harder rides on it. The point here is that you don't want to trust it at first so you ride a little slower and do frequent frame inspections. As it builds up a level of trust you can ride it harder, faster and longer in steps along with the same frequent inspections. At some point it will have either started to crack, as indicated by paint failures or other clues, or it will have earned your trust and you'll have yourself a useable frame. Whether or not it turns out to be useable for racing will depend on how you feel about it compared to some other frames by that point.

So, are the stays steel or not?

thanks BCRider, that's the most helpful advice yet- going to try the wood block idea this afternoon. Magnets stick to the stays, so I reckon they're steel. It was a free frame so I'm not too concerned if it doesn't work, but man would it be sweet if it does.

Try posting this in the Framebuilders section as well. You may get some good advice there too.

unbrokenchain, I used this in the past to check an aluminum frame...Get a ~ 6"length of all thread that'll fit into the drop outs and four nuts. Use the all thread to spread the drop outs to what the width would be with a hub and tighten. Place the frame on the floor and mark both sides of the bottom bracket tube and the insides of the drop outs. Using a square draw a straight line rearward for each side of the BB tube and then measure to that line from the drop out marks. They should be the same left and right.

I'm know there are better and more accurate methods so use this as a quick check.

Brad

well i got the spacing set so that a wheel will fit and the stays are even. i don't see any issues as far as cracking or other bends, so i'm going to get some more components in the next few weeks and see how this thing rides. thanks yall.