Help with Repair

I went to change the tire on my Nimbus Oracle 26. I found one of the 4 bolts that holds the wheel on was broken. The broken piece is recessed enough that grabbing it is out of the question.

Can I get away with 3 bolts? I may have ridden like that a long time already.

Should I drill it out (ruining the threading) and do a “cob-job” repair? I think there is enough space for this to easily work.

Is there some other solution?


Don’t drill it out. Use a screw/bolt extractor.

You mean run a screw in behind it and hope it screws out the backside?

No, there is a tool called a screw extractor, or an easy out. It will dig into what’s left of the bolt and unscrew it.

OK, thanks, just looked it up at Lowes, I will go but a kit tomorrow.

Bring it to your local bike shop if your unsure, bikeshops usualy have those kits in and are used to take broken bolts off :stuck_out_tongue:

I try to push it using another bolt first, dont screw too hard as you dont want to mess up the threads. It’ll most likely stay stuck because UDC usualy puts locktight on their bearing clamp bolts.

Not disagreeing but curious because I’ve never heard of that method before. How do you push a broken bolt out with another bolt? How can screwing in a second bolt from the other side possibly turn the original bolt?

You can also try drilling a hole through the center of the screw with a smaller drill bit - one that doesn’t come close to the threads. This is the first thing you’ll need to do to use a bolt extractor anyway, and there’s a better than not chance the drill bit will catch on the bolt and drive it all the way through anyway.

To do this, start by getting a center punch and hammer to make an indent in the center of the bolt to start the drill bit in the right place. This is very important; it is incredibly hard to keep the drill bit from walking over to the edge of the bolt and ruining your threads as you start drilling. Then drill your hole and I’ll bet the bolt screws all the way through before the hole goes all the way through the bolt.

As far as drill size - 3/16" is probably safe.


Friction. The second bolt will press onto the broken bolt, which will increase friction between the two, and if you are lucky enough, the broken of bolt now turns when you turn the new bolt and unscrews.

Just to throw another option out there that doesn’t require a bolt extractor set. Drill a small hole into the bolt from the backside, tap it, and screw a small bolt in there, which will allow you to get the broken of bit out by turning it. (I’d try this since I happen to have acces to a tap and die set, but not to a screw extractor set.)

Since you probably only need to overcome locktite (at worst) and little or no corrosion, this situation is likely an ideal situation for an easy out. I’d center punch the bolt to make sure you are drilling into the center of the bolt. Go very slow and do not put any side pressure on the easy out, as the smaller sizes break very easily. If you break an easy out in the bolt, you will need the services of a machinist with carbide cutters.

Another poster suggested drilling/tapping from the back side of the bolt. If the bolt was further away from the fork leg, that might work really well. However, being so close to the fork leg, you’re very likely to drill on an angle, or break a drill or tap.

As to living without the bolt… I wouldn’t do so, but I guess that is your choice.

Exactly, it rarely works, but it’s really easy and doesn’t require any specific tool. Worth a try. It worked a few times for me!

If it works, that’s great!
Did you get that bolt out, kayakzz?

Thanks all! I mail ordered the in/out tool. It arrived today and I had the broken piece out in a couple minutes.


Glad you were successful!

The threads don’t even look damaged, I wonder how the bolt broke :thinking: .


The screws for Nimbus Oracle 26s (probably most Nimbus products) that hold the wheel on are M6 x 1.0 x 20, available at Lowes for $2 for a two pack. Josh at UDC was cool enough to let me know it was a standard item and I sized it with the tread board.