Recently bought a '88 Trek 560, in great condition, I thought. Took it out, as it was warm here, got about 17 miles, and blew out the rear tire, loud, catastrophic failure, blew off the outer cover of what was apparently an old tire and tube. I stopped immediately, so shouldn't have damaged the rim at all, but now I see a few new problems.

One, the rim has pulled thru or broke off a part of the nipple?


Loose nipple? Whatever it is, this will fall down spoke....

Can this be fixed? Do I need a new rim? Or new just a new spoke?

Also, now the rear derailluer goes all the way to the spokes if I shift to lowest gear.

Is this bent?

Does this look bent? Was careful not to lay it on the drive side, not sure how it would be bent? Is there any adjustment? Again, '88 Trek 560

In my book, the rim is done. Sorry to deliver such a negative opinion but safety is really high on my build list for any bike.

Question. Why are there so many threads showing on the spoke?

That rim should probably be replaced. the loose bit isn't part of the spoke nipple, it's part of the rim, specifically the reinforcing eyelet It's what the spoke pulls against when tightened and it's no longer part of the rim. that spoke either has almost no tension on it, or if it does, it can spontaneously de-tension at any moment.

Not really repairable - putting a washer behind the spoke nipple isn't an option on a hollow-section rim. Sorry for the bad news.

Your derailleur hanger is bent and probably the derailleur bolt as well.

Yes unless there is some distortion the derailleur hanger is bent. Is it possible that when the tire blew/rim failed the rim went out of true, flexed, de-dished, whatever enough for the derailleur cage to catch in the spokes?

It didn't feel like it, I would have fell off, no ? Damn, this sucks, because I was truly pumped, felt like I got a great deal, and the warm day in November, plus the trust I put in the seller, made me take it out before having it all checked out. Didn't check the spokes like I should have, didn't look close at the derailleur, though it shifted fine when I picked it up, and I went up and down thru them all.

Something definetly happened to cause this damage, I just don't know if it was all from the blowout.

Blowout

I think if that damage were there before your tire blew, you would have felt it, so I wouldn't put it on the seller yet. An old rim with old spokes can sometimes spontaneously give way, especially if things were not quite set, like with a loose spoke (could have been the case since so many threads were showing on that spoke). It's definitely bad luck, and that sucks, but I suspect that might be all it is.

The rim should be replaced, as others are saying. On the upside, the derailleur hanger can be bent back easily with the right tool, and the derailleur, at least from that pic, looks like it may be just fine.

I feel for you... I know how great it feels to get out on a bike you're excited about.

I had a significantly bent dropout/hanger- I took it in to a shop- they have the tool to do it.

That's the spoke hole eyelet, pulled loose from the rim. Depending on the rim construction, it may be possible to re-peen it back into position. Remove the tire, rim tape/strip and spoke, support one side of the eyelet on something solid and use a blunt punch to re-peen it into place, like setting a rivet. This works best on single-wall rims; double wall rims have different eyelets and failure like yours would be difficult to fix. Also, check around the spoke hole for cracks or other damage. If there are cracks, the rim is failing and should be replaced. If it looks intact, but you can't get the eyelet re-set in the rim, you may be able to use a nipple washer on the inside to distribute the stress from the tensioned spoke and protect the rim. That was standard practice BITD before most rims had eyelets.

Looks like the inside wall of the rim has collapsed, leaving only the visible wall of the rim to support the spoke tension. Then the visible wall blew out, exposing the eyelet.
Often a tube will rupture as a result of the rim's inside wall collapsing.

The tire looks to have suffered an outer-ply delamination. Typically this happens only to aged or defective tires.
The three layers of tire casing under the tread are not woven, each ply has unidirectional threads which can allow the tube to blow outward between parallel threads and then burst.
This failure appears to involve two plies unless the single outer ply delaminated past the edge of the middle ply. Again though it's either advanced age or an insufficient-overlap defect that normally causes this to happen.
From the pictures, it appears that the old skinwall tire blew out, was then replaced with the Continental tire, and then the spoke eyelet pulled out(?).

The derailer hanger needs to be bent back to where the two pulleys both stay in a plane parallel to the sprockets even as the cage is rotated 90-degrees.

The rear wheel of a road bike is usually the most costly component to replace, and is the hardest to find in good, used condition since they are prone to failing before other major components do. So I always inspect any prospective purchase for rear wheel defects as much as anything else.

Thankfully it’s a steel frame, and hanger straightening is a quick job with the appropriate tool. I’ve fixed several of these in my volunteer work. Haven’t seen one yet where the derailleur bolt was also damaged.

I have personally come to the point in my life where I replace my bike tires before they start to look really bad and if I'm buying a used bike I figure in the cost of new tires before taking the first ride. Not saying I'm going to actually replace the tires but I calculate the cost in with the purchase. I have about 2000 miles that I put on a bike I bought used and still have the tires that came with it but I inspect them before every ride and have new tires ready to put on for next year. The tires that came with that bike are premium tires and are going to be replaced with premium tires. On another bike I had a pair of Performance Bike house brand tires with about less than 500 miles when both failed within two days of each other. You get what you pay for.

I had a blow out going down hill at a fairly fast pace and it scared the stuffing outa me. I regularly check the tires on my bikes and pressure. It can happen and cheaper or worn tires are the usual suspects. Joe

There are a number of threads with old trek matrix rims cracking at the spoke holes.

AS 6 speed is fairly forgiving, I probably straight that hanger myself.
I typically screw in a 3" M10 bolt and use that to straighten and not distort the mounting hole.

I’d say SOME double wall rims have different eyelets. Usually referred to as ”double eyelets”.
They’re a bit uncommon.
I don’t think I have any double eyelet rim in my inventory at the moment.
Most eyeletted double wall rims have a simple eyelet only attaching to the hubside wall of the double wall rim.

The original spec for the Matrix Iso rims called for nipple washers to be used, but no everybody used them.

Here is the rear derailleur when I bought it, although from a different angle. I must have bent it? I took the wheels off to replace the blown tires, and when I put them back on, I was on a hurry to try and get going before it got dark, and missed that the chain had come out of the bottom pulley and stuck, and when I jumped on and gave a push, it didn't move, and I had to dismount to try and see why. That must have been when it bent? I am really bummed, as I was enjoying this bike the little I had a chance to ride it.

Pretty much the same here.

There's a point where something is "fixable," and another point where something is "fixable, but not worth the effort or expense to fix." That point changes according to my financial state and what I'm willing to do.

I looked back on the pics of the bike as-bought and the driveline looked to be fine, though there was no shot directly from behind to confirm. But yeah, you may have bent it yourself in the scenario you described above. Not a big deal as you didn't destroy spokes or the derailleur as would normally happen in an overshift at speed. A shop can straighten that hanger back to normal in a jiffy and it shouldn't cost you much, either.

The rear rim, on the other hand, is toast. I had a similar issue with a Mavic rim early this summer, but in my case not only the eyelet but the surrounding material also failed and the eyelet pulled completely out of the rim with the spoke/nipple still attached. Rim went right into the trash. Cash outlay for new Mavic Elite (black anodized in my case as well), spokes, nipples and labor was nearly $200. A bit of a sting, but I've never had to replace a rim before; knock on wood it's another slew of years before I'll need to do it again.

The bike looks fantastic - like it was hardly ridden - so in my opinion, the outlay is worth it. Turns a $200 bike into a $400 bike, but you stole it at $200 anyway

I hope this all works out okay in the end!

DD

Some Mavic rims like the popular Open Pro are double wall/double eyelet. So is the H Plus Son tb14 rim, often recommended around here as a modern item with classic look.

https://www.universalcycles.com/shop...&category=4013

If possible get a pair of nuts, one each side, and do them up tight - that way you are not using the threads of the hole to transmit the bending stress, you are using the flanks of the dropout. With the cheapest form of dropouts-with-hangers this'll also lessen the likelyhood of elongating the hole, there isn't a lot of metal between the sides of the tang and the hole.

However, if you do use the nuts, remember to check that the seating surface (for the rear mech bolt) flatness, the nuts may hide a bend there.

That's a thoughtful post-mortem Chuckk.

The OP will want to observe while tightening the derailer bolt (after straightening the dropout) that the derailer doesn't rock as the bolt turns, would indicate a bent bolt. I've got a New 600EX rd here with a badly-bent mtg bolt.

Before I got a proper hanger alignment tool, I used to use a known-straight, long-cage rd to use as a hanger straightness indicator. Got the Microshift long cage mech from Nashbar for a few dollars and the cage was very long. I could swing the cage through 90-degrees rotation and observe the hanger alignment versus the larger cogs, checking for bend and for twist of the hanger. When the cage looked parallel to the cogs even an indexed setup always worked perfectly if everything else was in good order.

I might use a large adjustable wrench on this one for initial gross straightening, but only bend it with the rear wheel tightened into the frame backwards to support the dropout and to provide wrench clearance away from the cogs.
Did this a hundred times this way myself, always made sure the wrench jaw completely supported the hanger all the way around the hole so as not to distort the threaded hole(!).
This can be repetitive/tedious since the rear wheel needs to be reversed each time one bends the hanger and each time one checks the straigthness against the big cogs, so best to allow enough time to patiently do it right the first that one goes at it.

Great observation. Also - of all of the components on a vintage bike, rims are the one that can be swapped without in my opinion on taking away from the bike. Lots of aluminum rims from Mavic, Ambrosia, or Velo Orange can be purchased without IMHO causing the look of the bike to be altered to a state where I would no longer consider it vintage. Except for brake pads, cables and bar tape, rims are the next item on things on a bike you should plan on replacing a few times in the life of a good bike.

Replacing the rim is the conservative option, certainly what any bike shop would recommend in our litigious society.

For my own use, i would try to fix that wheel. If it fails, it will go out of true, but it will not collapse without warning.

Appreciate all the help, taking it to the local co-op this week, they say they have the tools and experience to give it a try. May ask about rims while there, to see what they have. Hope it goes well, I'll report back