ZHVelo

So I foolishly thought I could jump over a split in the tarmac, of course not, got a pinch flat. Fixed it at home, used the opportunity to clean the bike and put the rear wheel back. I noticed immediately that one part of the rim was rubbing the brake pad. And the wheel seems to be egging as we say in German, like wobbling. I can see that it isn't running perfectly straight, I can see the gap between the rim and the pad getting smaller, until it touches, then getting wider again as the wheel turns.

Now I don't know if it was doing that before and I just inadvertently adjusted the brakes while cleaning so now this wobbling means it hits the pad, or if this has something to do with the accident I had. Any thoughts? If I leave the pad adjuster (for when you want the wheel out, the thing you can flip so the pads move apart and you can take the wheel out), it doesn't rub, and actually the braking is still ok. Just feels as if it is a little bit loose (i.e. I have to pull the lever more than I usually do).

mprince

Your rim got knocked out of true, so it's a wheel issue, the brake is fine...

Koyote

Doesn't matter when or how it happened -- your wheel needs to be trued. Doesn't seem like you are equipped to do that yourself, but any good bike shop can do it in a few minutes.

Doc_Wui

If you can change a flat you can buy a spoke wrench and learn to trim up the wheel. However, if that seems too scary, take the bike to a shop and they can do it,

cxwrench

This is not a GD topic, post in 'bicycle mechanics' for stuff like this.

ZHVelo

I went through the list of forums and did not see that.

ZHVelo

Amazing, thank you, that really doesn't look too difficult.

Edit: Well, seems to be worse, I had a look and one of the spokes is completely loose, turnable by hand but nothing happens, looks like the entry to the rim is broken, it now looks like a hole, with the spoke going into it, whereas the others look more fixed, more connected.

unterhausen

moved here from General

pdlamb

There's your problem, then. You need to replace a spoke and nipple; $1-2 for the parts. Perhaps another $5-30 for tools if it's the drive side rear. If you haven't touched any other spoke with the wrench, you can simply put the new one in and tighten it, with some stress-relieving (look it up!) until the wheel's straight and true. If you get frustrated and just want to ride the bike, LBS around here will true it for the same labor they charge for replacing the spoke, around $25.

cyccommute 

When you say the “entry to the rim is broken”, does the spoke seem to be pulling out of the rim? If it is, you broken the rim and need a new rim or wheel. Pictures would help.

ZHVelo

Yes, in photo 3 you can see that the nipple sits smug in the opening into the rim. In picture 4 you can see a lot of black around the nipple, and the spoke itself is still in the nipple, but the nipple is totally loose in there.

I also noticed that (in picture 1) the tyre where the valve is seems to not sit perfectly anymore (compared to the front wheel in picture 2)

Bill Kapaun

Pics are pretty blurry, but I "think" I see a spoke thread exposed. Sometimes the pic is too close to focus properly.
That would mean the spoke got so loose, the nipple has backed off. Probably non drive side (NDS) spokes?

IF you are very new to this, I'd have a shop true AND TENSION the wheel.
It's easy for a beginner to induce a severe hop in the wheel if you need to tighten a large amount of spokes.
You can "pluck" spokes and listen to the sound to get an idea how even the tension is. (DS have more tension than NDS, so will have a higher pitch)
If you take it to a shop, remove the tire & rim tape to reduce labor costs.

79pmooney

Question - can you slide the spoke out of the nipple? In other words, have the nipple threads stripped? If so, you need a new nipple. (It is also possible that the spoke broke at the start of the threads, You will see that right away because the spoke will pull out very easily but I doubt that is the case because it should have already come if that were true.

To replace a nipple, you remove tire and tube, pull back the rim strip tape over the spoke holes, shake the nipple out and replace. (Trick - screw the new nipple onto another spoke backwards. Stick through the hole from the tire side. Screw onto spoke. Grab nipple with spoke wrench and unscrew your starter spoke. Many of us cut down that starter spoke, screw a nipple on in regular fashion tight, bend a nice handle into the spoke and have a very useful spoke starter tool.)

You may have to replace the rimstrip tape after peeling it up. Not all re-stick satisfactorily. The very common Velox tape does. It has been my preferred rimstrip for many years, Might be worth picking up a roll when you by the new (2) spokes and nipples. (2) so you can make the tool.

I understand if you don't want to go through all this. But you might just find working on bikes is fun!

Ben

cyccommute 

It looks like the bead is has trapped the grommet on the inner tube. Deflate the tire...NOW!..., unscrew the nut on the valve and push the tube up into the tire. If you leave it there, the tube will eventually herniate from under the tire and a low noise will result.


The good news is that it doesn’t look like the rim is broken. You didn’t pull a nipple through. You have two different styles of nipples there. I would suspect that the square nipple is broken. It looks like it might be aluminum and they can break. It needs to be replaced. It would be better to replace it with a nipple that matches the other nipples. If they are square, then replace with a square one, if they are splined, replace with one that is splined. It will make wheel work easier down the line.

ZHVelo

I used a different tube and it looks exactly the same. What are the chances that "the bead has trapped the grommet on the inner tube" (not sure what that means) in both cases?

That is good news, thanks.

cxwrench

It means that the reinforced part of the tube around the valve is not fully inside the tire, the tube is preventing the bead of the tire from fully seating against the hook of the rim. Push the valve towards the tire a few times (into the tire) and then pull down. The bead of the tire should now be engaging the hook of the time and the line on the tire casing will look consistent rather than having that bulge like yours now does. I can't think of a better way to describe it w/o posting a video of what we're talking about. I feel like I just said the same thing @cyccomute did but I just used more words.

Bill Kapaun

With just a bit of pressure in the tire- So you can basically still push the beads together with thumb & forefinger-
Push valve stem in-
Massage bead to bead seat-
Pull valve back out-

cyccommute 

The chances of the grommet on the tube being trapped between two different tubes is fairly high if you aren’t aware of the problem. The valve grommet is the part of the tube that is circled. This one is fairly large but all tubes have them.


You can trap the tube under the tire and when you pump it up, the tube will sneak out from under the bead and cause a blowout.



When you put a tube in a tire, push the stem up into the tire (red arrow) and then pull it down (green arrow). This will put the grommet on the right side of the bead.

Bill Kapaun

All this tire seating is kind of moot until the rim is "fixed".

ZHVelo

Thank you for the explanation, and yes I decided to give it to a LBS to check out, don't feel confident in seeing if I can properly fix it.