Caution: Wheel Bolt Torque Issue

[kenk]

While living in Washington D.C. in 2001, a BMW rider had a rear wheel bolt failure on his R1100RT, resulting in the wheel coming off at interstate speeds. The conventional wisdom at the time was the bolts weren’t properly tightened to the recommended torque requirements. The bolts eventually worked loose to the point where they broke under stress. However, can bolt failure occur if over-tightened?

While changing the rear tire on my R1150GS, I accidentally tightened the rear wheel bolts to 105 Ft lbs vs. 105 Nm. BMW recommends 105 Nm or 77 Ft lbs. My large ½ drive torque wrench clicked on three out of the four bolts. However, the fourth bolt wouldn't tighten. So I removed the bolt and noticed the metal had weakened and stretched (see photo). So I removed the other three bolts and noticed slight stretching, but nothing to the degree of this bolt. By simply over-tightening the bolts from the recommended 105 Nm to over 140Nm (105 Ft lbs), the bolts stretched to a point where they could have broken in the hub or on the road while operating the bike.

An additional word of caution. The rear wheel bolts are not universal on all BMWs. My R1100RT and K1100LT rear wheels use a 60mm bolt. My K1200RS rear wheel uses a 55mm bolt. My R1150GS uses a 63mm bolt. Mixing the wrong sized bolts could have disastrous consequences.

Even if you have a dealer change your tires, I would recommend checking the rear wheel bolt torque after the bike returns from the dealer. For those of us that change our own tires, paying careful attention to the torque specification is very important.

The Top Bolt is new. The Bottom Bolt was over-torqued.
http://i205.photobucket.com/albums/bb12/kenk_bucket/DSCN23611.jpg

[HFD190]

Good post! Any sense of how many miles you rode with the over-tightened bolts to cause that damage?

[kenk]

Good post! Any sense of how many miles you rode with the over-tightened bolts to cause that damage?

That was all torque wrench damage. So I rode no miles with the over-torqued bolts. Since I over-tightened all four bolts, I replaced all of them with new bolts.

I do plan on removing all the rear wheel bolts from all my BMWs and inspecting for similar damage. Since the bolts are only $5 a piece, its a cheap fix.

[r11rs94]

That was all torque wrench damage. So I rode no miles with the over-torqued bolts. Since I over-tightened all four bolts, I replaced all of them with new bolts.

I do plan on removing all the rear wheel bolts from all my BMWs and inspecting for similar damage. Since the bolts are only $5 a piece, its a cheap fix.

Just asking, but when you but them back at 105 ft lbs., were you standing on the wrench to get them this tight. Either that or you are one strong dude.

[kenk]

Just asking, but when you but them back at 105 Ft lbs., were you standing on the wrench to get them this tight. Either that or you are one strong dude.

I was using a 1/2 Drive Craftsman Torque Wrench capable of torquing to 210 Nm or 150 ft lbs. The long handle makes it very easy to torque to 75 Ft lbs. I have used a 3/8 Drive Craftsman Torque Wrench in the past for rear wheel bolts. However, the 3/8 drive is limited to 100 Nm or 75 Ft lbs. So, I broke my 3/8 Drive Torque Wrench by torquing beyond its manufactured capability (105 Nm).

The rear wheel bolts came off an R1150GS with only 38,000 miles. I bought the bike two years ago with only 1,200 miles. Since that point, I've changed 4-5 rear tires on this bike. I have never over-torqued the rear wheel bolts on this bike because previous tires were torqued with the 3/8 Drive Torque Wrench. To be on the safe side, I replaced all the rear wheel bolts with new ones.

[19991100RT]

Have a look and count the threads on those bolts. 14 look right? Here is some insight on just how important correct torque is.
The first two threads of any bolt carry a full 50 percent of all torque on the bolt. The last thread carries 25 percent of all torque load and thus, the remaining threads carry 25 percent of load.
Your pic shows the damaged bolt if used in it's condition would have only carried at best 50 percent of it's Engineered load or another way to put it.... try riding with only half of the wheel bolts in place. Makes me scared!
Quite often, Mechanics will use torque limiting extensions on the air tools. These in effect stop applying drive to the bolts at the design torque no mater how long or hard the bolt is being driven. Simple terms are the extension twist rather than turn the bolt once the design torque is met. Over years of use, these limiters become less reliable so, who knows what torque has been applied. Best advise is (as written above) is always check the torque values with your own "well kept, properly stored and used" torque ratchet
:deal

[bradleypurple]

Checking torque on a bolt that you didn't install wouldn't be good. You would literally have to remove them to get an accurate torque. Torque values are extremely important especially when you think of the failure modes of over torqued bolt on a motorcycle wheel.

Also you bring up a good point about cyclical stresses on those bolts. How often should they be replaced. In theory, if properly torqued they should be good for a very long time.

[kenk]

It's great to have an engineer comment on this subject that understands the properties of metal far greater than I do. All the rear wheel bolts stretched to some degree. Engineers describe this as the elastic properties of material using "Youg's Modulus" or "Modulus of Elasticity". The bolt in the photo stretched to a point where it could no longer be torqued, but yet could be removed. That's because the stretched portion does not rest in the hub threads. Only 1/2 the threads do. I think this is positive because it show the bolts were engineered with enough elasticity to stretch and not break; even when torqued 35% greater than recommended on the specifications. However, the stretched portion has no external support. Stretched steel that doesn't return to it original length is weakened steel and could end in failure.

[Jfixit]

I've read that you should reduce torque a certain percentage if an anti sieze is used, I usually don't. Is that a mistake?

[henzilla]

I've read that you should reduce torque a certain percentage if an anti sieze is used, I usually don't. Is that a mistake?

If you are talking wheel bolts...never oil or put anti sieze on them.
But ,yes to any change from a dry bolt will alter the readings...a few bolts are recommended to oil prior in certain engine building steps,and the torque ratings are adjusted for that.

And on the OP...YIKES! can see how that can happen on almost any clicker or digital scale wrench...I ALWAYS put my glasses on and check twice...almost done it myself.

[PGlaves]

I've read that you should reduce torque a certain percentage if an anti sieze is used, I usually don't. Is that a mistake?

In simple terms there are two components to the torque reading - actually resistance to torque or resistance to twisting - that you see with your torque wrench. One of those components is the clamping force developed by the pitch (circular inclined plane) of the threads, and the other component is friction - a little under the head of the bolt but mostly friction along the threads.

The torque specification provided by the manufacturer has two components. A numerical specification in ft. lbs. (or newton meters or inch pounds) and a thread condition - ie "lightly oiled" "clean and dry", etc.

If you vary the thread condition from that specified then you have altered the friction component of the resistance to torque (twisting) so the number specified is no longer the right number. In this specific case - using anti seize where "clean and dry" is the spec. - means that at the same number you have lower friction and higher clamping force. Higher enough clamping force that you risk thread failure or elongation of the bolt as shown by Ken in the original picture in this forum thread.

I don't recommend anti seize on wheel bolts. If you have used it then you do need to reduce the measured resistance to torque to account for the reduced friction. How much is a bit of a question but the rule of thumb is from 25% to 33% less measured resistance to torque to avoid damage to threads or elongation of the bolts.

[nrpetersen]

The loss of developed bolt shank load from head friction component is roughly the same as the thread friction component. The threads are loaded at an angle causing a wedge effect, but the bolt head is presented with the same axial force but at a larger average diameter.

To each his own I guess, but in my pre-retirement engineering life torquing bolts without anti seize (actually we used Moly paste) was a no-no for any critical fasteners. Many times we took bolts beyond yield, and our mechanics developed a pretty good feel for the onset of plastic deformation of smaller fasteners without a torque wrench.

Using a series of long 1/2-13NC 180,000 psi SPS socket head cap screws, I personally ran developed-load tests on various lubricants & as dry. Antiseize gave the most consistent results. This allowed us to get a greater and more consistent preload from a given bolt. Interestingly we needed only grade 2 nuts to fail grade 8 or 9 fasteners.

We also tried a couple of our mechanics in a blind test to see how repeatable they were without torque wrench, only to find they did about as well as the torque wrenched ones, except they averaged a little tighter.

It is possible that BMW's logic to leave the threads dry is to prevent them from loosening without creating excessive wedging action in the aluminum wheel under the wheel bolt heads, but frankly, I'd be more concerned about thread damage and corrosion effects.

Observation - do a disproportionate share of torquing errors come from clicker type wrenches?

MN MechEngr

[JerryAttrick]

I already had two torque wrenches of the torsion beam style (3/8" and 1/2") left over from being a motorcycle mechanic shortly after bikes were invented. Last month, I bought a pair of Craftsman click-style wrenches for the BMWs.
The old wrenches are probably unchanged from the day of purchase, but they have one drawback. You have to have your eye aligned 90 degrees from the scale to read them, and somebody put a sidecar body right where my head needed to be. The click-style wrenches can be used accurately without looking at anything.
For initial confidence in the clickers I calibrated them at work, but that option won't last forever. The long term plan for confidence tests is to connect two wrenches of the same range together using an Allen socket and hex socket, and the handles pointing in opposite directions. (Two people required.) The center part where the wrenches meet are placed on a wood block or other appropriate fulcrum. Both handles will be pressed down until the click, while the operator with the torsion bar wrench reads the highest number achieved.
The logic is this: The torsion-beam wrenches are very stable over time, and have no failure mechanism that could result in significant errors while appearing to be correct. The same can not be said for the clickers, where the critical parts are not visible. So any time in the future, if the two styles of wrench are in agreement, I feel the new clickers are not plotting my untimely end.
Comments?

[moondog]

As a former aircraft tech. all my torque wrenches were calibrated once a year. Not sure if it was a FAA requirement or company but I wasn't arguing. If a rider finds him or herself using a torque wrench and wants a peace of mind about the accuracy of the wrench I would recommend finding a company that does calibration. In Connecticut there was one in Windsor Locks that my company used. I don't know what the expense was because I never paid to have it done. There is probably one local where ever you may be or within reasonable shipping distance. My .02

[Rich]

Another thing on torquing your wheel bolts that hasn't been mentioned yet is to tighten the bolts to an initial value, and then to the final torque value. I don't have the settings in my head and I'm not about to run out to the garage, but read your manuals and follow directions. There are reasons for this, namely getting a nice even torque on all the bolts.

[heychooch]

I had a little problem last time i torqued the rear wheel. I use a clicker type torque wrench. I torqued the bolts to the first setting of 50 Nm and everything was fine. When i set it to 105 Nm i torqued two of the bolts and all was well. When i got closer to the torque on the third bolt it started giving me a squeaky creaking feeling like it was dry or something. Not smooth at all. It creaked so bad i couldn't tell if my torque wrench clicked or if it was just the wheel creaking. I loosened all the bolts and started over. Same thing happened again on the third bolt. This time i made sure it was a different bolt just in case it was one of the bolts. I tightened the last bolt and went back over all the bolts. All clicked at 105 Nm so i know there all tight enough but did i over torque that one bolt. I don't know. I did clean all the bolts and wheel wedges by wire brushing them so there was no corrosion on them. They were (ahem) ...squeaky clean. This sometimes happens with lug nuts on a car but on the bike i don't like it. I did check the bolts before i put them on the wheel. None were stretched. They all looked good. Anyone have any suggestions on how this can be avoided? Is it me?

[PGlaves]

The loss of developed bolt shank load from head friction component is roughly the same as the thread friction component. The threads are loaded at an angle causing a wedge effect, but the bolt head is presented with the same axial force but at a larger average diameter.

To each his own I guess, but in my pre-retirement engineering life torquing bolts without anti seize (actually we used Moly paste) was a no-no for any critical fasteners. Many times we took bolts beyond yield, and our mechanics developed a pretty good feel for the onset of plastic deformation of smaller fasteners without a torque wrench.

Using a series of long 1/2-13NC 180,000 psi SPS socket head cap screws, I personally ran developed-load tests on various lubricants & as dry. Antiseize gave the most consistent results. This allowed us to get a greater and more consistent preload from a given bolt. Interestingly we needed only grade 2 nuts to fail grade 8 or 9 fasteners.

We also tried a couple of our mechanics in a blind test to see how repeatable they were without torque wrench, only to find they did about as well as the torque wrenched ones, except they averaged a little tighter.

It is possible that BMW's logic to leave the threads dry is to prevent them from loosening without creating excessive wedging action in the aluminum wheel under the wheel bolt heads, but frankly, I'd be more concerned about thread damage and corrosion effects.

Observation - do a disproportionate share of torquing errors come from clicker type wrenches?

MN MechEngr

If by this post you are intending to recommend a revised torque procedure for these wheel bolts that is different than the BMW specification of 105nm, threads clean and dry, by advocating the use of anti seize or moly paste - then at least revise both the thread condition and the numerical specification. It sounds like you are advising that anti seize or moly are good in your opinion as a registered professional engineer. If you are saying that anti seize is good and moly is good - and the 105nm can stay the same then I think you are advising a condition that will over stress the threads and or bolt shank and risk a dangerous condition.

[vetbmwrider]

Last spring I had almost lost my rear tire on my R1200c because the bolts worked them self loose. I was lucky that day. All I have to say is check them often and make sure you carry a 17mm wrench to retight those bolts to get you to a safe area to tight them to spec.

[nrpetersen]

Expanding my comments on the above posts:

OP Kenk - 105 NM on a lubed bolt is way too much as you now know. A bolt in simple preload can still perform satisfactorily if accidentally over torqued but the pictured one is grossly yielded. Your note on bolt length is VERY important.

R11S94 - 77 Ft lbs on a 1/2 inch drive isn't that hard to get.

19991100RT - I agree except the use of air tools to achieve torque is questionable as the tool's drive line (any extensions, and the socket type and wall thickness) is a substantial variable. A final torque wrench verification should be done for each setup.

Bradleypurple - Cyclic stress will quickly fatigue a bolt. That's why it is important to generate enough preload that there is no cyclic motion in a joint. Bolt threads are otherwise recognized to have a stress concentration factor of about 6!

Kenk - Typically in important but routine bolt applications there is about 1/3 again torque before a bolt yields. But yielding in itself is not that bad as long as the distortion is within reasonable limits. For example, headbolts on newer car engines are routinely tightened to a substantial rotation after a set torque is achieved. The manufacturer uses the bolt heat treat properties to plan on the bolt to be yielded to get the desired preload on the head. Those bolts are not intended to be reused.

JFixit, Henzilla, & PGlaves The torque reduction of 1/4 to 1/3 is reasonable for the use of antiseize. Be sure to use a dab under the head too then.

nrp - no comment------

Jerry Attrick - Using a beam type wrench to verify a clicker type calibration is an excellent concept. I have cheap clickers and am not at all impressed with the apparent accuracy of the same.

Moondog - (where do these names come from?) Calibration per FAA standards is probably quite expen$ive (like everything else in aviation) and is probably mostly CYA and really uneeded - except for Beech center section carry-through bolts etc.

Rich and Heycooch - The squeaky threads described are scary and are my main concern with unlubed threads.

PGlaves - Antiseize is good in my opinion ("to each his own"). Your torque reductions for such use is reasonable.

VetBMWRider - Good idea.

I was a PE in MN and MA for 30+ years, but now 6 years after retirement, am no longer registered (is there registration for curmudgeons?).:bikes

[Rich]

Last spring I had almost lost my rear tire on my R1200c because the bolts worked them self loose.


I have to ask, we're they originally torqued to proper specs? Without lube as the manual states?

[bradleypurple]

To nrpeterson, you certainly understand the concept of Torque, as it seems all persons in this thread do but if I had to give a grade for response, you definitely receive the A+.

[kenk]

If cyclic stress will quickly fatigue a bolt, should older bolts that have stretched through normal used be replaced? Does anyone have any information on when a bolt is stretched beyond serviceability?

The rear wheel bolts on an R1100RT that has never been over-torqued. How do I know? Because I previously only used a 3/8 drive Craftsman Torque wrench manufactured to a limit of 100 Nm. My R1100RT has 112,000 miles on the clock. If you figure I've replaced the rear tire approximately every 7,000 miles, that equals 16 rear tire changes in the past 13 years. The rear wheel bolts are 60mm bolts. However, they have stretched through normal service to 62mm. Since the bolts are only $5 each, should I replace these bolts?

I know many folks that don't use a torque wrench to tighten rear wheel bolts or any bolt on their BMW motorcycles. We all understand the dangers of not properly tightening a bolt. So many of us give that bolt that little extra effort to make sure its tight. Unwittingly, we may be compromising the structural integrity of the bolts.

[nrpetersen]

If you can't see that it's stretched (although the picture above is one of the most stretched I've ever seen), it probably hasn't yielded enough to be concerned about it. A small amount of previous-application yielding doesn't compromise the clamp load capability of a bolt. Age doesn't affect strength either.

There even comes a point in bolt applications where I don't like to arbitrarily replace them - especially if they are plated. If the bolt happens to be cracked and you don't know it, you will fail it when initially tightening it up. If the plater hasn't done his job right, brittle fracture (from hydrogen embrittlement) can happen several hours after a bolt has been tightened. I suspect BMW watches that very closely for critical fasteners.

If the wheel-axle flange is flexing in service due to an inadequate preload, you have other problems..........

Geez - wheel bolt torquing is like an oil thread!

[Rich]

So if a bolt stretched like the picture shows, which is extreme, what happened to the receiving threads??

[moondog]

"Moondog - (where do these names come from?) Calibration per FAA standards is probably quite expen$ive (like everything else in aviation) and is probably mostly CYA and really uneeded - except for Beech center section carry-through bolts etc."

Name comes from aviation workmate.

I disagree with your comment about "unneeded". Think about the picture of the bolt at the beginning of this thread. You want a bolt holding on a wing or engine to look like that? Didn't think so. It was never CYA. It was peace of mind. That the job was done right. How about the rider who lost his wheel? You think he wants his wrench calibrated next time? Thought so.

Yea aviation is expensive. You can't pull over to the side of the road if something breaks or comes lose....

[moondog]

To nrpeterson, you certainly understand the concept of Torque, as it seems all persons in this thread do but if I had to give a grade for response, you definitely receive the A+.

Don't swell his head...

[nrpetersen]

"Moondog - (where do these names come from?) I disagree with your comment about "unneeded". Think about the picture of the bolt at the beginning of this thread. You want a bolt holding on a wing or engine to look like that? Didn't think so. It was never CYA. It was peace of mind. That the job was done right. How about the rider who lost his wheel? You think he wants his wrench calibrated next time? Most aviation airframe applications load bolts in shear, so a torque error isn't critical. Engine cylinder base and rod bolts are specified to be lubed w oil to get a repeatible preload, and if the only thing I had was a clicker torque wrench, I'd want it calibrated today. Otherwise, if it was a 3/8 drive bending beam wrench that would repeat its zero, that would be enough for me. The FAA makes no distinction.

The OP must have continued to try to reach the book torque even though the fastener (or something) was obviously yielding - and for several turns at that.

[kenk]

So if a bolt stretched like the picture shows, which is extreme, what happened to the receiving threads??

There appears to be no damage to the receiving threads. The rear wheel bolt stretched portion does not rest in the final drive crown gear threads. Only 1/2 the threads (about the first seven turns) secures to the final drive. The stretched portion has no external support.

The rear wheel bolts appear to be softer metal. Replacing the crown gear set for boogered up bolt threads would cost $563, not counting shims and seals.

[nrpetersen]

Kenk - If you have at least 1 thread diameter of good thread enagagement, you should be OK. Be sure the new bolt isn't bottoming out though. In this type of application that would be a really bad situation.

[JerryAttrick]

In all of this excellant discussion, nobody has mentioned safety wire. Has anyone ever considered some sort of after-torque retaining system to guarantee that they won't be backing themselves out?
I understand that if everything is put together right, the bolts aren't going anywhere. But for all of us belt-and-suspenders types, it would be a nice security blanket.

[kenk]

One of the learning points for me from this rear wheel bolt issue is proper torquing is required to properly seat the rear wheel bolts, as well as insuring you don't over-torque the bolts. Over-tightening the rear wheel bolts can stretch and permanently damage them.

However, most flats that I have experienced over the years occur on the road. I changed or fixed four tires on the road in the past couple years alone. One repair was in six inches of mud, just south of the Arctic Circle on the Dempster Highway, Yukon. You can't pick your flats. I personally don't travel with a torque wrench. I don't know anyone that does. Helge Pedersen states in one of his videos that he believes the BMW tools are designed to not allow a person the ability to over-torque based on their size. However, the rear wheel bolt wrench come with a cheater. So, what do many of us do when we have a cheater? We use our leg to put that little bit of extra effort to snug down the bolt. We learned this technique when changing car tires.

So, I like to practice replacing tires on my GS my using the side stand as bead breaker and only the tools I have on the bike; replicating the same conditions when on the road. Part of my practice technique will now include learning the approximate amount of pressure to apply to seat the rear wheel bolts, then following up with a torque wrench to check the values afterwards. I may not need the cheater. I certainly won't use my foot. I will also add a rear wheel bolt to my packaging list of spare parts.

[nrpetersen]

Safety wire on preloaded tension fasteners is pretty much only for keeping the fastener parts around after failure.

In our wheel mounting application, if a bolt is going to work its way loose, safety wire won't be strong enough to keep it in place. The preload will be lost, and the bolt will soon fail from cyclic loading. Reliability depends on an adequate joint preload.

The best machinery joints are those preloaded together with long bolts and good enough mating surfaces that there can be no flexing. Many of the aircraft con rod and cylinder base nuts referred to above are not being wired or cotter keyed anymore. They depend on bolt/stud shank stretch.

[MotorradMike]

Interesting thread!

Somebody mentioned checking your wrench against another set to the same torque. I did that once and they both clicked at the same time - very reassuring.

There is another very accurate way. Simply hang a 10Lb weight at the end of a 2foot stick, cobble up a drive square and use your wrench to torque the load against gravity. Set at 20 foot pounds, it should just click as the stick goes horizontal.

And if you're fussy, look up the force of gravity in your town and compensate accordingly.

[vetbmwrider]

I have to ask, we're they originally torqued to proper specs? Without lube as the manual states?

To be honest dealer had to remove the tire for another issue. I just put blind faith in the dealer to have done correct.

[GlobalRider]

I grease my wheel bolts.

35 years later...I've never lost a bolt, they've never loosened, I've never snapped a bolt, I've never stretched or damaged a bolt, I've never distorted anything causing some type of failure.

Luck, I guess, even after 35 years.

[kenk]

I think we are really talking about damage that rarely occurs, unless we violate the extremes at both ends. I doubt (don't really know) that the rear wheel bolts would work themselves loose at 75Nm vs 105Nm. Likewise, I doubt you can damage a rear wheel bolt if you tighten to 120 Nm vs. 105 Nm.

However, I do know at the extremes at both ends, they will either work loose or permanently damage by stretching. I also know for some bikes that have higher miles and eat tires, the bolts will stretch a couple mm over the years from cyclic stress. Is this a problem? :dunno

For the engineers that design these products, its rocket science. However, for us users of the product, we just need to pay attention to detail when torquing bolts. Simple distractions can have serious consequences.

[nrpetersen]

Likewise, I doubt you can damage a rear wheel bolt if you tighten to 120 Nm vs. 105 Nm.

However, I do know at the extremes at both ends, they will either work loose or permanently damage by stretching. I also know for some bikes that have higher miles and eat tires, the bolts will stretch a couple mm over the years from cyclic stress. Is this a problem? :dunno

For the engineers that design these products, its rocket science. However, for us users of the product, we just need to pay attention to detail when torquing bolts. Simple distractions can have serious consequences.

If you can see that a bolt has been stretched, it really should be replaced - especially if it has also or will be exposed to fatigue.

It isn't necessary for the load to go to zero for fatigue. The greater the static load, the less of a superimposed cyclic load it takes to start a crack (Miner's rule) - even if the fastener is not deformed plastically.

The fancy words for it are cumulative fatigue damage. The higher the load cycles, the fewer cycles it will take to initiate a crack - and cracks propagate to eventual failures under fatigue loading. If the preload is adequate, there will be near zero fatigue loading. But if the preload is inadequate, there will be high cycle fatigue.

A bolt that is too loose will many times fail before one that is too tight in a fatigue situation.

On the other hand, 120 NM is a lot of torque for what, a 12 mm bolt? And the aluminum hub could also start cracking from the wedging action of those special tapered washers BMW uses.

[knary]

Does anyone else not use a torque wrench on those bolts? :lol

[BubbaZanetti]

Does anyone else not use a torque wrench on those bolts? :lol

threads like these always make me wonder just how out of spec my 4 year old, beat and battered and uncalibrated torque wrench really is.

[knary]

threads like these always make me wonder just how out of spec my 4 year old, beat and battered and uncalibrated torque wrench really is.

Is that the only thing they make you wonder about? :ha

[Rich]

I was riding with a non-hotrodding harley riding friend a couple of years ago and we had just left a little restaurant after a fine day of riding. We were both taking off in different directions to head home, and as I rode away I saw him swing his leg back over the seat to get off, and then he was kneeling down. When I got back to see if he had problems, sure enough he did. The rear sprocket had sheared all five bolts off from the wheel. The pulley spun free and pretty much disintegrated his wheel.

My point is, if you don't already: Use a torque wrench.

[beckgr]

This is a very interesting thread. Great info. I have a question. I have a torque wrench that has the "clicks" as you reach your torque setting. How many clicks to I listen for? Is it the first one and then back off, or does it just keeping clicking without applying too much pressure?

[Rich]

One click, you are done.

[beckgr]

Great, thank you.

[knary]

My point is, if you don't already: Use a torque wrench.

No.
And you can't make me.

[kenk]

I was riding with a non-hotrodding harley riding friend a couple of years ago and we had just left a little restaurant after a fine day of riding. We were both taking off in different directions to head home, and as I rode away I saw him swing his leg back over the seat to get off, and then he was kneeling down. When I got back to see if he had problems, sure enough he did. The rear sprocket had sheared all five bolts off from the wheel. The pulley spun free and pretty much disintegrated his wheel.

My point is, if you don't already: Use a torque wrench.

I wonder if the dealer mounted the rear wheel? Regardless, whether the dealer mounts a tire or you do, I would recommend checking the rear wheel bolts as part of regular maintenance with a torque wrench.

BMW recommends checking the rear wheel bolts at the 600 mile check on their maintenance schedule. Its the same on all the maintenance schedules for all my BMWs. Although only listed on the 600 mile check, I recheck the torque on the rear wheel bolts after the first ride on all new rear tires.

http://i205.photobucket.com/albums/bb12/kenk_bucket/MaintenanceSchedule.jpg

[MCMXCIVRS]

I wonder if the dealer mounted the rear wheel? Regardless, whether the dealer mounts a tire or you do, I would recommend checking the rear wheel bolts as part of regular maintenance with a torque wrench.

BMW recommends checking the rear wheel bolts at the 600 mile check on their maintenance schedule. Its the same on all the maintenance schedules for all my BMWs. Although only listed on the 600 mile check, I recheck the torque on the rear wheel bolts after the first ride on all new rear tires.

http://i205.photobucket.com/albums/bb12/kenk_bucket/MaintenanceSchedule.jpg

I agree with the need for re-torquing wheel bolts within a few hundred Km of the installation. This has become pretty much standard procedure for automotive and heavy duty applications. Since the BMW rear wheel uses a similar mounting bolt to those applications, it only makes sense to apply this policy to our motorcycles.

[Rich]

No.
And you can't make me.

:nyah Your wheel is going to fall off. :nyah

[henzilla]

threads like these always make me wonder just how out of spec my 4 year old, beat and battered and uncalibrated torque wrench really is.

or my grandfathers 1950's beam model I still use at times...needle still rests at 0 in spite of me

[henzilla]

Does anyone else not use a torque wrench on those bolts? :lol

I used to do it by feel like I have always done on my four wheeled vehicles and trailers...when the 1100's wheel started wobbling at 70 MPH one day...I thought I should change habits on two wheeled vehicles..." I THOUGHT it was tight" was not going to sound good if it happened while Helen was riding it.

[queretaro]

I used to do it by feel like I have always done on my four wheeled vehicles and trailers...when the 1100's wheel started wobbling at 70 MPH one day...I thought I should change habits on two wheeled vehicles..." I THOUGHT it was tight" was not going to sound good if it happened while Helen was riding it.

Truer words were never spoke.