Wheel Came Off!

I noticed a vibration on the freeway and thought my front tire was vibrating because it is worn out.  Wrong!  The back wheel pulled 3 bolts out with the threads.  Looks like I'll be needing a new flange at least.
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Gotta make sure they are torqued correctly.

Scary business and you’re not the first. I recall 2 or 3 others reporting the same in previous posts here. Luckily nobody’s crashed as far as I remember. I check mine weekly. 110 Nm and make sure you have an accurate wrench. Some of the Chinesium ones are dangerously inaccurate. Thanks for sharing. Everyone needs to be aware.

That first happened to me on a Breva 1100 when it was first released.  Bad workshop prep was to blame, I reckon.

Could have been quite serious.

I ended up using Loctite to discourage them form loosening again.

Yep.  How hard and expensive is it to replace the flange?  Just glad I didn't end up in the hospital!  It fully locked the brake about 20 feet after I pulled off the freeway.

Wow.  

You, Sir, are a lucky man.  That could have been catastrophic, with this space being used to say what a nice guy you were.

I need to check more frequently than I do.  

"Once a week" would get a success rate about the same as my New Year's resolutions and Lenten promises, but I will do more than I do now, which is only at servicing fluids.

Hope the repair costs are not too $teep.

Bill

Didn't know this was a common problem on the CARCSs...
110 Nm (cross pattern I guess?), any kind of mild thread lock?
When we change wheels on a car we torque the bolts, drive for some tiime and then check the torque again, but this is not enough on the CARCs?
Stupid questions, maybe, but can't afford to go wrong here...

It's not common. I think it's been reported here 2 or 3 times. If you correctly torque the screws, they won't come loose. I don't let any non GRiSO person touch mine, and I routinely check mine every few months anyway.

One of the reasons I like the wire wheels is I can check the paint marks on the bolts at the same time I check the tire pressure and oil level -- Often!

We do know a local rider who actually lost the rear wheel on his Norge and crashed. He and his pillion were both pretty banged up, but not seriously injured, luckily. That inspired me to do this when I did the swingarm bearing service.

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Street wrote:

We do know a local rider who actually lost the rear wheel on his Norge and crashed. He and his pillion were both pretty banged up, but not seriously injured, luckily. That inspired me to do this when I did the swingarm bearing service.

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You know, I was just thinking about safety wire when I saw your post.  Easy enough to do.

I have nobody to blame but yours truly for the torque on the bolts.  I did it in a cross pattern with a 3/8" breaker bar and a 12" extension about as tight as it would go.  That was about 1,500 miles ago.  I noticed the wobbling sensation about 120 miles before it came off.  Lesson learned!

PS, the last thing you will hear before the wheel locks up is the faint sound of your plastic hub cover bouncing off the road!

Looks like I'm in for a wallet lightening. Looking at item #1 here. I  don't think you can buy just the flange but the entire bevel drive is toast.  Ideas? [You must be registered and logged in to see this image.]

Drill them out and put thread inserts in.

What Sideshowbob said.

Properly installed Heli-coil inserts will be fine. No thread locking compounds on Heli-coil unless you want to reinstall new inserts every time the wheel is removed. A machine shop that does thread repair should be able to set you straight. It'll not be cheap but less than the new Bevel Gear Kit, if you can get it.

Yes, you're one lucky dude.

The hub is incredibly hard. I don't know exactly how they are hardened but it's probably by more than heat.

Before panicking though it would probably be worth buying a good quality, (ie NOT Harbour Freight!) tap and seeing if you can clean the threads up. If you can't? Buy a second hand bevelbox and do all the 'Fix' things to it before installation. Please send the old one to me and I'll replace the flange with one from a dead crownwheel here. Actually thinking about it that won't work as the threads are actually in the crownwheel, not the spindle. Sorry. I'm sitting at the side of the Great Ocean Road in Victoria. Not near a CARC!

The only one I've ever had a wheel come loose on was Mark Salkeld's bike. Now I know it was torqued 'Correctly' but it was done with my old torque wrench and although it had been recalibrated in living memory it can't of been good enough. Luckily no harm done. I'm super careful nowadays!

If you could machine out the damaged threads using a tungsten carbide bit or the like a Time-Sert might work but I wouldn't trust a helicoil in this application.

The only

just thinking out loud, would it help to replace the bolts each time the wheel comes off?

that's a lot of torque, I could imagine that the bolts get stretched after 2 or 3 cycles of tightening...

scary stuff!

Pete, would you mind driving over here for a service call (again) . I hear the National Rally is in San Diego this year....

So if the torque is 110nm (please correct me if I am wrong) what is the best/most accurate torque wrench can one buy without breaking the bank. I currently use a warren and brown torque wrench (Australian).
Also what would be a good range on the torque wrench to cover most applications in the shed when working on our bikes.
Your thoughts and experiences most appreciated.

alanlemansiv wrote:

So if the torque is 110nm (please correct me if I am  wrong) what is the best/most accurate  torque wrench can one buy without  breaking the  bank.

Are you torquing them dry or lubricated? There's a helluva difference. The best way is to measure bolt stretch, but this is impractical for many situations.

This is why I stopped using a torque wrench and use my right arm to "feel" the correct amount. YMMV.

Yeah, if your nuts (bolts in this case) are not tight, this will happen. Feels odd when it starts, really odd. Tighten them nuts boys and girls!

Can anyone give me the thread pitch of the lug bolts?  I think they are 1.50 but maybe 1.25?  I found an Irwin brand tap that looks good to me.  I'm hoping the bolts are much softer than the flange so it might not be too bad....

I too am a fan of the old tech beam torque wrenches. I have one of those fancy click style, it even says Snap-On on it. It doesn't often come out of it's case.

I grew up wrenching on farm equipment, often brand new, as we were John Deere dealers. I never used a torque wrench until I started working on motorcycles, instead relying on the "elbow strain" to get it right. My stuff didn't break, nor did they fall apart.

Oh, the thread lubricant....without looking it up in the manual, I'd say a light spritz of something like WD-40 or even diesel fuel would suffice. Nothing more. Just clean, VERY lightly lubed threads. I'd ask Pete to correct me if that's not right.

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Adding a lubricant affects the final torque tension value, except possibly in the case of WD-40, which isn't a lubricant. If you're adding an actual lubricant, you shouldn't be torquing to 110Nm. Since I don't know the actual tension values of the hub and bolts, mine will remain dry and torqued to 110Nm by my calibrated torque wrench.
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