Broken Swing Arm Bolt

[Thumper35]

I fully agree that when these go wrong they really go wrong, however, there are a few things you can try before you take it to a machine shop. Know when to stop what you are doing and making it worse before you "just try one more time" is the trick. Soak it with PB Blaster over night and then use what we call in the ship yard an easy out. It is a kit that comes with a drill and a bit. The drill treads and bit rotate opposite to the regular direction on the threads. Drill the hole in the very center of the broken off bolt and then simply insert the bit with the drill still set to the opposite rotation and back it out.

Edited June 18, 2013 by Thumper35

[rgray556]

There are a lot of ways to get it out. Weld a nut to it and then soak it with penetrating oil while it is hot is a good one (small wire feed will do).

Another would be to buy a set of rounded bolt extractors from home depot or somewhere like that, they are the same concept as an easy out but grip on the outside. They go down to really small sizes and it looks like there is just a little sticking out. Heat it with a torch pretty good and cool it with penetrating oil like above so it gets sucked into threads.

Instead of an easy out, use a torx socket (a quality steel one, not the soft cheap ones) because a lot of easy outs that are found at auto stores are junk. Find the torx size that is AT LEAST 1/2 the size of the bolt, but not wider than the inside of the threads. Get a drill bit a little smaller than the torx bit and drill the bolt about as deep as the torx bit is and as close to center as possible. Beat in the torx then heat and use penetrating oil to cool. This is how I do most of my small broken bolts that are broke flush. Just get a good torx as the cheap ones will twist off and you will be where you started at.

Unless the shop you take it to has specialized machinery they will probably do something similar to what has been stated by me or others anyways. I doubt you can get the aluminum hot enough to cause problems with a small propane torch, there is a lot of surface area and aluminum transfers heat well.

I dont know how the subject changed but it was about a swing arm, now it is a spark plug hole.

When I worked on Fords I had a couple vehicles come in with stripped spark plug holes that were on 4.6l and 5.4l engines. What I did was pulled heads and put in inserts. It was pretty easy, the kits came with 3 taps, inserts and locks. I just pulled heads and used the first tap to get the hole started straight, then the second would put the correct size through to the comb. chamber. The insert would go in next with tapered locks that you had to tap in with a punch. The 3rd tap would then go through the insert and thread the locks. It took a little time, but you didnt have to worry adout them stripping again, and loctite on the outside of the insert sealed them good.

I work on heavy equipment now and caterpillar uses similar inserts when a bolt hole strips, so there may be something that is made for dirt bikes or a kit that will work.

If not, maybe you can find a good deal on a complete or stripped head.

Edited June 18, 2013 by rgray556

[Dragon67]

If whatever OP is still following this and has not solved the problem yet part of the solution is PB Blaster. Just let it soak the bolt over a night or two. Next, based on the picture, use a Dremel with a cutting wheel to cut a slot in the middle (diameter) of the bolt. Then use a flat screwdriver to remove the bolt.

Heat is fine. I would use a heat gun if necessary (not a torch) but I think the combo of PBBlaster and flat-head screwdriver would be my first attempt. If you start backing it out and it gets stuck, turn it back in a bit and apply more PB Blaster. Honestly, the stuff works wonders if you let it work.

If that fails, which it won't, easy-out is still an option. If that fails, a machine shop is still an option. I guess. If necessary. . .

[Dragon67]

I thought I just responded to this, but I guess I will try again. Based on the picture, the first step would be to soak the bolt in PB Blaster overnight or maybe over two nights. Stuff works great if you give it time. Then use a Dremel to cut a slot in the diameter of the bolt. Looks like there is a lot sticking out there, so this is an easy solution. Once the slot is cut, use a large flat-head screwdriver to remove it. . .

never mind, my post from before just showed up. maybe there is a delay on this thread?

[Eddie8v]

See that little white plastic brake line holder a bit forward on the swingarm? Remove the Phillip's head bolts that hold it down. You'll now have easy access to the internal cavity of the swingarm, where the rusted-end of the bolt resides. This rusted end is typically the reason you can't remove the bolt as once you start backing it out a turn or two, you're now into the bunged-up rusted threads that sit in there and corroded over time. Squirt a boatload of PB Blaster down that small attachment screw's hole while tipping the swingarm up to keep the liquid PB residing on the end of that bolt. Let it sit for a day or so, then have at it. You're welcome.

Edited June 19, 2013 by Eddie8v

[FORMA MOTO]

I notched mine, screwed it IN to the swingarm, and left it inside.

And no, I never hear it bouncing around.

[Power-Dome]

Good info about the access to the other side of the bolt. I haven't touched this since I broke the bolt last Friday and every now and then I hit the area with PB blaster. I figure I'll keep doing this until I get time this weekend to attack the problem.

My first inclination is to remove swingarm and bring it somewhere to have a nut welded on. Then I will purchase a small propane torch and use a combination of heat, PB blaster, and light impact to jostle the bond and attempt to back it out.

I think the mods got a hold of this thread and moved it around and changed the title on me. I originally had the thread in general dirt bike discussion because I figured this problem was not specific to CRF450's.

Thanks to everyone for the input.

[Power-Dome]

It was strange. I thought I had posted in a dream because the thread seemed to vanish from my history. Then it wound up in CRF450R with a different title. The only thing I saw wrong with my original post was the title. If someone were searching for a thread about broken swingarm bolts, they would not have found it given the title I had previously.

[Ud_Luz]

It was strange. I thought I had posted in a dream because the thread seemed to vanish from my history. Then it wound up in CRF450R with a different title. The only thing I saw wrong with my original post was the title. If someone were searching for a thread about broken swingarm bolts, they would not have found it given the title I had previously.

A moderator accidentally merged it with the wrong thread and then corrected it.

[Thumper35]

Did you get it out yet ?

[Alan Marshall]

the torx way is the best it never fails drill a hold in the centre of the bolt about 3/4 the side of it get a quality torx bit a little bigger that the hole and taper the end of the torx bit, put a dab of coarse grinding paste on the end of it and hammer it in as far as possible , then get your heat tortch and heat the aluminium for a minute around the bolt thread then unscrew it gently, thats the best way , ofcoarse welding a washer on it then a nut will definetly take it out but thats a last resort, a easyout or reverse threat tool will only expand it ,

[KXcam22]

It tough to weld that close to the aluminum swingarm without marking it. If it was my bike, soak it in something ( gunpowder solvent works amazingly well as a rust loosening penetrant), drill a pilot hole and then use an easy out or a bolt extractor. Easy outs are tapered square shafts and the bolt extractor is a round tapered shaft with a reverse swirl of threads on it to grab the inside of the hole. I like the idea of just screwing it into the swing arm. Never thought of that. Hope this helps. Cam.

[Power-Dome]

Status update:

I've routinely been hitting the bolt with PB Blaster. It's been a long week at work and tomorrow I will have some time to try and attack the bolt. My first inclination is wanting to weld a nut on. Maybe a series of tacks around the nut and letting that cool before filling a nice plug weld. another option I am considering is slotting the bolt and then attempting to get movement with a manual impact driver.

On a side not, I went to remove my swingarm this evening and my dang pivot bolt will not come out. The nut came off fine but I'm having trouble getting the bolt out.