ryoanji

I purchased this wheelset secondhand quite a while ago, American Classic 420. It stayed perfectly true and round, and I was very happy with it. A few days ago, while descending I didn't quite see a rough patch on the road and got a pinch flat on the rear. The wheel also came a bit out of true.

I tried truing it, but couple of nipples were very hard to turn. I applied a little bit more force and nipple snapped in half horizontally (perpendicular to the spoke). I never seen something like that. When the same thing happened to second nipple, I stopped. Was wheelbuilder using some kind of threadlocker? I was using PT spoke 4-sided spoke wrenches. Nipples are aluminum.

Can someone please tell me how can I get the broken nipple out of the spoke? Then how should I proceed truing the wheel, a lot of nipples are tight.

KBentley57

if you haven't, put a drop of penetrating lube around the base of each nipple and let it set for a few minutes before you start.

As far as getting the other nipple out; you can probably unscrew it from the back side, after removing the tire and rim tape. If that doesn't work, gently use some channel locks and see if you can break it loose. If all else fails, you'll just have to cut the spoke and replace it.

ryoanji

Will give it a try.

fietsbob

Aluminum Nips , apparently , Not surprised they broke . Try Brass "

I apply anti sieze to the spoke threads when I build wheels ..

There is a screwdriver slot inside on the head end

ryoanji

How frequent is nipples seizing to spokes in your experience? I thought about unscrewing from the nipple head, but the spoke sticks out too much, I can't really grab the slot.

fietsbob

I surmise you had half the nip shearing off because the threads seized. between steel spoke & Alloy Nip.


Ah perhaps the spoke was too long ? a Proper spoke length comes to the bottom of the slot in the head..

Make a tool out of a small Diameter tube of steel .. file it until there are 2 spanner pins protruding

to fit over the protruding spoke and un screw the Nip?

some security screw sets do similar a center pin in the bolt keeps it from being unscrewd with common tools ...


What did 'American Classic' reply when you asked Them?




...

ryoanji

To be honest, I didn't asked AC. The wheelset was bought secondhand, so I am not the original owner. But what is most important is that I think the rear wheel was rebuilt some point. AC420 were known for rear wheels spokes braking (too light), so whoever sold them to me got the rear one rebuilt with beefy wheelsmith 2.0 spokes.

FBinNY 

Most likely, the problem isn't the nipple, ir's the rim. Generally rims are drilled after anodizing. This leaves bare, unprotected aluminum at the holes. Water wicks in carrying various road salts, then evaporates leaving the salts to accumulate and attract the rim.

When aluminum corrodes it expands, so the holes shrink onto the nipples holding them very tightly, and they break when you turn them. Obviously having aluminum nipples doesn't help, but brass nipples get frozen just as easily when the hole shrinks.

Ronno6

If you have a small enough file, file a slot in the center of a screwdriver blade to allow for the spoke.