Shock mount bolt snapped - help (82 GL1100)

[NotSoLilCrippseys]

Today, just as I was ready to bolt up the grab bar and take my '82 project for her maiden voyage up/down the street, disaster struck!

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I had those shocks on and off perhaps 6 times in the last 6 weeks, and don't recall ever putting any serious torque on them. Strange.

I did a search on issues with shock mounts and found a post by toomanybikes that included the following image.

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I'm wondering if what I'm seeing means I COULD extract the shock mount from the frame and install a different one by simply threading it into the frame. (I didn't think I could do that, as all seemed welded up on my visual inspections.)

If I'm seeing things incorrectly, what are my options here? Get a welder to add threads to the post on the frame? Not sure an epoxy like JB Weld would do the trick.

[flyin900]

Cut it off flush with the outer mount of the shock assy ( it looks like a thread or two remaining on that stub) and get a threaded stud or cutoff bolt of the correct TP and metric size as the original broken off piece. Drill the cut off flat surface on the stub and cut new threads with a tap into this new hole for the stud. Double nut the stud and screw it into the tapped hole to the correct outer length for the broken off piece.
Use red Loctite to secure the threads of the stud going into the repaired hole.

Hopefully you have these tools available for the repair or can borrow them from a friend.

Oh FYI, what your seeing from "Toomanybikes" is a stud from the rear end drive of the Goldwing. It is from the right hand side and the lower right rear shock then mounts onto that stud.

Totally different that what your dealing with and your correct that these upper studs are welded at the factory into the frame.

[NotSoLilCrippseys]

Thanks for the guidance.

As I lack the tools or a friend with a tap/die set, looks like I'm in for a tool purchase and on-the-job trial and error.

I thought that photo showed something different from what I have. But then wishful thinking plays tricks on the mind.

[toomanybikes]

sorry to see the snap. As already mentioned, that was from the lower shock mount in the final drive, not the upper on the frame.

One of my other bikes has a similarly mangled shock mount. Someone has already welded on a replacement, but maybe i'll cut that off and try the method described here.

[Whiskerfish]

The stud looks fine. I would center drill it and tap for a large flat head screw like a binding screw. All it has to do is keep the shock from sliding off. No real load.

[NotSoLilCrippseys]

Toomanybikes: Weld was my first thought, actually, but I also imagined a bit of a "mess" in that spot.

Whiskerfish: The mount is definitely solid, and there's about 1/2 a turn of thread left. I'm planning on running the bags on the bike, so there will be some load.

I do like the idea of a bolt/screw.

My only concern was in weakening the shock mount strength by drilling it. I suppose the bolt compensates.

[pidjones]

Having a small lathe, I would drill the plug out of the frame and turn a new mount to weld (won't need much welding) in.

I had a footpeg mounting bolt break on a GL1000. Was able to center drill and tap for a 6mm bolt and washer as the full body of the bolt supporting the peg was still there. I'm still careful not to stress it, though.

[Sagebrush]

I might explore the possibility of removing the stud completely and through bolting it. Might even have the bolt welded in place to act as a stud.

I'm sure it would be extra work but your confidence in the through bolt would be greater than a drilled stud. Make sure you use a proper grade bolt to withstand the shear forces applied by the shock.

[NotSoLilCrippseys]

Oh, to have PidJones' tools/skills.

Sagebrush: Not sure what grade the bolt would need to be, but I'm thinking pretty strong.

Welding a stud to the frame means dismantling much of what I've put back on the bike and getting the frame or rolling chassis to a shop, as I don't weld.

I'm pretty frustrated, but I'll learn some things through it. And it's not like I don't have other bikes to ride.

I'm not going to be able to take the work on for another week or three, as work has been crazy - with no end in sight.

[desertrefugee]

The stud looks fine. I would center drill it and tap for a large flat head screw like a binding screw. All it has to do is keep the shock from sliding off. No real load.

This is actually pretty good advice here. I had a similar thing happen on a bike once on a long trip. I had enough of the stud left under there to slip the shock over. Then I used several loops of bailing wire to hold it on and finished another 600 miles before I got home.

[pjlogue]

I would be hesitant to effect a make do repair to a suspension component on a bike of this size. I.E., drilling into the stud and using a bolt to hold on the shock. If it were to fail while negotiating a turn at speed (perhaps over some bumps) the results would not be good. Honda, when they designed these bikes, did not use a lot of "overkill" in a lot of the frame because of cost and weight. That stud diameter is probably the smallest the engineers thought was safe. Drilling into it will weaken it even if there is a bolt to replace the removed material. Either cut the stud off and weld a new one on or cut the stud off and drill out what is left and use a good grade bolt through the frame to replace it.

-P.

[Sagebrush]

Having a small lathe, I would drill the plug out of the frame and turn a new mount to weld (won't need much welding) in.

Oh, to have PidJones' tools/skills.

You can measure and take pictures of the good stud on the other side and then take them to a machine shop to have one made. Then you just need a welder. Sounds complicated but then you would be confident of the repair and it would be easier than swapping everything over to a new frame to get the same results.

(Yeah I know, you didn't mention swapping to a new frame but I bet you thought about it )

[pidjones]

I drilled and tapped a footpeg mounting bolt. And it is probably risky at that (I keep my weight off of it).

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The shock mounts undergo much more stress including hard shock loading. I suggest you drill it out of the frame and replace.

[Sidecar Bob]

The stud looks fine. I would center drill it and tap for a large flat head screw like a binding screw. All it has to do is keep the shock from sliding off. No real load.

This is what I'd probably do too except I would use a regular hex head bolt and a large washer and maybe see if I could find a spacer that would fit inside the end of the grab.
You wouldn't want to drill too big enough hole in the stud to weaken it but an M8 or 5/16" would be more than strong enough to keep the shock's eye and the end of the grab in place. I think I would remove the shock and grind the broken end flat before I tried drilling into it too.

[ericheath]

If you choose to put a boot through, keep in mind the tire can come up into the area. Too big a protrusion might cause contact over larger bumps when fully laden.