Loose hub bolts

[77 golden eagle]

this is what im talking about..

 

[coldair]

All the race track bikes I've worked on have safety wire on everything works really good.

 

[tarry99]

this is what im talking about..

Here's the tool, the wire and some random special bolts for reference that are drilled specifically for "Safety Wire" .........Everything in my race car is Safety Wired.

You will have to drill the head yourself for almost all course threads bolts as the racing industry mostly uses only fine thread........no big deal as mentioned above using a good drill press vise and cobalt drill bits...........
I used head drilled Allen bolts on my hubs and never have they come loose.........of course if you want to take them off you have to cut the wire.

 

[Rescue Diver]

After reading all of this, I had to run back down to the garage to check mine! Is this problem specific to Warn hubs? My hubs are AVM and they've never come loose, even after the beating I gave them last Sunday at Kansas Rocks with the front locked. Mine are regular old external, and they bolt to the standard 5 bolt hub the same way a Warn does, so you'd think they would have the same problem? I'm just using stainless bolts and lock washers.

 

[tarry99]

After reading all of this, I had to run back down to the garage to check mine! Is this problem specific to Warn hubs? My hubs are AVM and they've never come loose, even after the beating I gave them last Sunday at Kansas Rocks with the front locked. Mine are regular old external, and they bolt to the standard 5 bolt hub the same way a Warn does, so you'd think they would have the same problem? I'm just using stainless bolts and lock washers.

Rescue,

I think for the most part a lot of different hubs have the same problem with loose bolts........I have not given it much thought why they come loose but the most obvious would be just the transfer of torque through the hub , axle and tire...........I have safety wired mine since the 1970's so I never had an issue. Studs, locknuts, locktite, star lock washers are all common fixes that sometimes work........what people tend to not understand is once the thread has been stretched and work hardened by being loosened and tightened over several cycles the thread becomes worn out.
The key in high stress applications is to apply the proper torque and maintain that stretch by some locking devise hence the use of Safety Wire.
If someone has this problem I would heli-coil the threads.

 

[Rescue Diver]

Rescue,

I think for the most part a lot of different hubs have the same problem with loose bolts........I have not given it much thought why they come loose but the most obvious would be just the transfer of torque through the hub , axle and tire...........I have safety wired mine since the 1970's so I never had an issue. Studs, locknuts, locktite, star lock washers are all common fixes that sometimes work........what people tend to not understand is once the thread has been stretched and work hardened by being loosened and tightened over several cycles the thread becomes worn out.
The key in high stress applications is to apply the proper torque and maintain that stretch by some locking devise hence the use of Safety Wire.
If someone has this problem I would heli-coil the threads.

Are we talking about the threads in the hub itself, or something in the lockout? I thought the problem was the holes elongating in the lockout that the bolts go through and then thread into the hub?

 

[tarry99]

Are we talking about the threads in the hub itself, or something in the lockout? I thought the problem was the holes elongating in the lockout that the bolts go through and then thread into the hub?

The elongation is the after effect once the bolt comes loose..........if the bolt did not come loose there would be no twisting motion IE; Elongation.
Keep the bolt / thread tight stops the motion & stops the problem...............and yes I am talking about the threads wearing out. Once the bolt is loose and I'm not talking about finger tight, just a 1/16 turn and the thread bore is now subject to a twisting motion and the bore slowly becomes elongated and over sized. At this point the thread will not hold since the contact area in the root of the thread has been upset..........If you have a standard machinery handbook handy there are several chapters on thread design inside.

 

[Rescue Diver]

The elongation is the after effect once the bolt comes loose..........if the bolt did not come loose there would be no twisting motion IE; Elongation.
Keep the bolt / thread tight stops the motion & stops the problem...............and yes I am talking about the threads wearing out. Once the bolt is loose and I'm not talking about finger tight, just a 1/16 turn and the thread bore is now subject to a twisting motion and the bore slowly becomes elongated and over sized. At this point the thread will not hold since the contact area in the root of the thread has been upset..........If you have a standard machinery handbook handy there are several chapters on thread design inside.

Could the problem be that Warn comes with bolts that are too short? The stainless bolts I'm using go way deep in the hub threads. They're the same length as what came with my AVM hubs when I bought them used.

 

[tarry99]

Could the problem be that Warn comes with bolts that are too short? The stainless bolts I'm using go way deep in the hub threads. They're the same length as what came with my AVM hubs when I bought them used.

It could be a number of reasons........I would bet that each time an aluminum hub has been tightened and loosened the area behind the washer or bolt has been roughed up and compromised to the point there is not a flat surface anymore.
I would say that looking at the Warn hubs with the cast aluminum housing if I wanted to improve upon them I would probably counter sink a hardened washer in each of the six bolt locations...............that alone would probably fix the problem as now there would be a flat hardened area to tighten against and not the soft aluminum. You could also use a floating hardened washer but I would then at least spot face each location to make sure it was flat..........
In your case stainless is hard and brittle & should normally be used with an anti-seize when threaded into a dissimilar metal. Now I'm not saying you should change anything if its working but stainless has that bad habit of galling other metals.

 

[Rescue Diver]

With so many people posting in this one thread that their bolts have come loose, I'd really like to know if every one of them was using Warn hubs? If so, that's a surprise because aren't Warn supposed to be the best?

 

[tarry99]

With so many people posting in this one thread that their bolts have come loose, I'd really like to know if every one of them was using Warn hubs? If so, that's a surprise because aren't Warn supposed to be the best?

I know for a fact that a lot of them do use the Warn Premium Hub which is a good product........but it really doesn't matter what hubs are being used its more so the tightening techniques that are most important..............
I still have an old set of Cutlass Hubs on the shelf made out of steel and chrome plated.......... pretty much bullet proof. Went out of Business, made to good of product.