Huzband Posted August 18, 2006 Share Posted August 18, 2006 I pulled the rear wheel last night for a tire change. The bolts were a bit tough to break loose, & when they did, it was more of a pop than just normal torque. They also show slight corrosion. This is the first time I've had the wheel off in the 7k/2 months I've owned it. The bike has 22k & I don't know the service history. So, I'm strongly considering applying a light dab of anti-sieze to the threads upon install. Unless you know of a definite reason not to. Thanks. Link to comment
BMWRich58 Posted August 18, 2006 Share Posted August 18, 2006 Some do some don't, just like the oil threads,matter of personal opinion. Do what makes you feel comfortable. Link to comment
Smoky Posted August 18, 2006 Share Posted August 18, 2006 I use a small amount of anti-seize. Link to comment
PrinceAZ Posted August 18, 2006 Share Posted August 18, 2006 No. Anything on the threads will change the torque applied, and this is critical! (Unless of course you want to chase your rear wheel down the road.) What I recommend is cleaning the threads with CLR or similar rust remover, then washing and drying them throughly. I also have found a buildup of rust in the hub and they are harder to clean, but should be done too. I have replaced the bolts once at 40k miles and think in the future I will do them at every other tire change. They cost less than $4 a piece at Bike Bandit. Link to comment
bmwmick Posted August 18, 2006 Share Posted August 18, 2006 Clean and dry is what the service manual says. Anti-seize can allow the bolts to loosen and you don't want that. You can hit the bolts with a wire brush to clean off the corrosion. Mick Tucson Link to comment
RFW Posted August 18, 2006 Share Posted August 18, 2006 So, I'm strongly considering applying a light dab of anti-sieze to the threads upon install. Unless you know of a definite reason not to. All you need is a light coating of ordinary grease on the threads. It'll work as well as anything. Used this for 40 years with no problems. Link to comment
steve.foote Posted August 18, 2006 Share Posted August 18, 2006 I have to strongly disagree with the use of any lubricant or anti-sieze. PrinceAZ and bmwmick are absolutely correct on this (looks like an Arizona conspiracy here ) Seriously, no lube. Clean and dry, torqued to proper spec. Link to comment
bmwmick Posted August 18, 2006 Share Posted August 18, 2006 I have to strongly disagree with the use of any lubricant or anti-sieze. PrinceAZ and bmwmick are absolutely correct on this (looks like an Arizona conspiracy here ) Seriously, no lube. Clean and dry, torqued to proper spec. Yeh, but it's a DRY BOLT Mick Tucson Link to comment
ShovelStrokeEd Posted August 18, 2006 Share Posted August 18, 2006 OK, a little lesson in bolts and nuts 101. First off, the manual specifies clean and dry threads for the torque used. A bolt is an elastic device. It works, and holds its position by stretching of the material of the bolt due to the clamping forces applied. Torque specifications are carefully engineered to apply the proper amount of stretch to the bolt to achieve the clamping force desired under the conditions specified. While there is little danger that a bolt torqued to specification with lubricated threads rather than dry will loosen, there is a very real danger of exceeding the stress level that the bolt can withstand which can lead to failure of the bolt or the threaded portion of the assembly. Even if the bolt doesn't snap off, it may stretch beyond its elastic limit and instead of providing the clamping force it is supposed to, and incindentally keeping your wheel on, it will be as if you failed to tighten it in the first place. The wheel lugs are in real danger of this as they have a hardened washer between the taper and the head of the bolt and that greatly reduces the friction forces when tightening the lug. Stay with what the engineers recommend on this one. They do actually learn this kind of stuff in school and the good ones apply it. If they wanted you to lubricate the threads, they would have told you so. Link to comment
John Dickens Posted August 18, 2006 Share Posted August 18, 2006 Why do we get so introspective about every issue? Cars have lots of wheel nuts or bolts and I bet car drivers don't really give a damn. Some of them go very fast too. Personally I do use copper grease on the rear wheel bolts but I also understand the issues involved in the stress and torsion of said bolts. I guess it's an educated personal choice Link to comment
SageRider Posted August 18, 2006 Share Posted August 18, 2006 Why do we get so introspective about every issue? Cars have lots of wheel nuts or bolts and I bet car drivers don't really give a damn. Some of them go very fast too. Personally I do use copper grease on the rear wheel bolts but I also understand the issues involved in the stress and torsion of said bolts. I guess it's an educated personal choice Where is the "educated" part of the choice in going against manufacturer's directions? Please tell me how cars are directly applicable to our motorcycles? Link to comment
T__ Posted August 18, 2006 Share Posted August 18, 2006 Huzband, my 1150RT BMW service manual specifically has a warning about NOT greasing or lubricating the wheel bolts or mating flanges.. "36 20 Installing rear wheel e Attention: The contact faces on the spacer (3), the rear wheel drive and the wheel hub must be free from grease and clean. Do not scrape the wheel – mask it off if necessary. • Place the rear wheel in position with spacer (3). e Attention: Only use wheel studs with length code 55. Do not oil or grease wheel studs! • Hand-tighten wheel studs (1) with taper rings (2). • Tighten the wheel studs (1) in diagonally opposite sequence" Twisty Link to comment
Joe Frickin' Friday Posted August 18, 2006 Share Posted August 18, 2006 Why do we get so introspective about every issue? Wouldn't be much of a discussion board if we didn't discuss things. There is a pretty basic formula that relates applied torque, bolt diameter, and bolt tension/preload: T = K * F * d Where T = applied torque (the torque spec) K = torque coefficient F = bolt tension (preload) d = bolt diameter Just make sure you get your torque and diameter in compatible units. IOW, either the torque is expressed in N*mm and the bolt diameter in mm, or torque in N*m and bolt diameter in m. The torque coefficient, K, accounts for thread surface condition, geometry, pitch, and lubrication. The math is pretty ugly, but the fact is that because of friction, thread pitch differences don't matter much until you get to ludicrous thread pitch angles; IOW, where torque vs. preload is concerned, UNC or UNF really doesn't matter. But lubrication does. Here's a table, from Shigley & Mischke's "Mechanical Engineering Design:" Nonplated, black finish: K = 0.30 Zinc-plated: K = 0.20 Lubricated: K = 0.18 Cadmium-plated: K = 0.16 Anti-seize: K = 0.12 As you can see, the torque coefficient can vary widely with conditions. Heck, just replace your original black-finish bolt with cad-plated, and you could nearly double the bolt tension for a given torque. Likewise with going from zinc-plated to slathered with anti-seize. "Lubricated" is pretty ill-defined; it's not clear whether they're talking about WD-40, sewing machine oil, or bearing grease. And that's the problem: you just don't know what kind of K-factor you're getting when you deviate from what the manual says. As Ed points out, excessive preload may plasticly distort the bolt, in which case you're not even getting the expected preload. OTOH, the bolt may take it without a problem, but you just don't know unless you know what the bolt grade/class is, and have crunched the numbers. And even if the bolt can take it, the over-spec preload may distort sealing surfaces or damage parts. One guy may get away with it ("been using lubed bolts for XXX miles now"), but may be within a hair's breadth of catastrophic failure and not know it; the next guy may use a more slippery lube or torque it a smidge tighter, or hit a slightly bigger bump, and have his overstressed wheel hub crack to pieces at 80 MPH. Bottom line: if you haven't done preload-versus-torque testing for the thread conditions you're working with, then it's a shot in the dark. BMW has determined the optimum preload and the thread/torque conditions that are most likely to get you close to it; if you deviate from those conditions, you're not likely to hit the desired preload. I'm not saying you will crash/burn/die, but you definitely are adding an unknown factor into things. If you have a concern about excessive corrosion, I'd recommend simply buying new bolts. Link to comment
Huzband Posted August 18, 2006 Author Share Posted August 18, 2006 Well Ed, once again, thanks for more than just answering the question. Your responses, & Mitch's too, always go beyond the "some do, some don't" answers. The info ya'll give is most appreciated. Thank you both. Link to comment
RFW Posted August 18, 2006 Share Posted August 18, 2006 I have to strongly disagree with the use of any lubricant or anti-sieze. PrinceAZ and bmwmick are absolutely correct on this (looks like an Arizona conspiracy here ) Seriously, no lube. Clean and dry, torqued to proper spec. Man! After I have put a dab of grease on wheel bolts/nuts (both on bikes and cars) for 42 years now, and the only "problem" I ever had was that the bolts/nuts never siezed or were ever hard to remove, this is a fine time to tell me that it doesn't work! Reminds me of the saying "Those of you who say it won't work, are really annoying those of us who have already done it!" More seriously, exactly what are the engineering reasons for your disagreement? For starters, if one reason is the fear that a lubed thread will somehow loosen, at the torque that wheel bolts are required to be tightened, that is not a valid engineering reason. Link to comment
Albert Posted August 18, 2006 Share Posted August 18, 2006 I think I'd agree with you Bob. If for no other reason than consistency. I've checked one engineering reference that indicates as much as 10:1 differences for unlubricated torque. I'd sooner take my chances with slight, consistent overtorque than have values all over the board. Not to cause any debate on this but can those of you who use a synthetic lubricant on your lugs please post the brand and why. Please justify your answer with an example. Link to comment
Paul Mihalka Posted August 18, 2006 Share Posted August 18, 2006 I am terrible. I don't put anything on my wheel bolts. They never have time to stick, the wheel gets a new tire every three month or so. For fifty years or so, car wheels, and the last twenty years bike wheels with lug bolts, I "torque" them with a long wrench to two grunts. I absolutely don't recommend this method to anybody, but it works for me. Besides, not everybody has calibrated grunts Link to comment
russell_bynum Posted August 18, 2006 Share Posted August 18, 2006 More seriously, exactly what are the engineering reasons for your disagreement? See Mitch's post, above for details. Link to comment
Dances_With_Wiener_Dogs Posted August 18, 2006 Share Posted August 18, 2006 Besides, not everybody has calibrated grunts Link to comment
GordonB Posted August 19, 2006 Share Posted August 19, 2006 Bottom line.....If it requires torguing, it DOES NOT get lubed or anti seized. Link to comment
Smoky Posted August 19, 2006 Share Posted August 19, 2006 I usually use a very samll amount of anti-seize. Last year when I got tires mounted at a rally, by one of the big dealers that was doing dozens a day, I found they used a big amount of copper coloured anti-seize. There was enough on there for a couple of tire changes. In June I put new rubber on the bike for my trip to Alaska. The last of the copper stuff was wearing thin, so I wiped it off, and put my usual amount of anti-seize. I always use the tools from the bike, so I know I have the right stuff in case of need on the road. And I use the one-grunt method of torquing. However, this time I thought that wheels and tires going to Alaska needed to be properly torqued. So out came the fancy wrench, and I torqued 'em to spec. Six weeks later I was back in my shop putting on another back tire. I was shocked at how easy those wheel nuts came loose. They have always been much tighter with the one-grunt method. I guess I have been over-torquing them all along. I guess I'll go to a half-grunt in the future. Link to comment
Phill Posted August 19, 2006 Share Posted August 19, 2006 yes I use small amout of Copper grease too and Torqued to spec. Never had any problems either nor never had any come loose. Link to comment
Eckhard Grohe Posted August 19, 2006 Share Posted August 19, 2006 A wonderful explanation of bolt torque whys and wherefores. And they still don't get it. For the non believers I would like to say that these torques are calculated to give safety factors that will allow the bike withstand a variety of operating conditions and allow for a variety of manufacturing tolerances. Over torquing does not guarantee failure but reduces the safety factor that the assembly has. To site a particular case, I think Smoky's bike has experienced bolt stretch, because the bolts seemed too loose when he removed the wheel, and if he continues to use the bolts he may be getting into a world of trouble. I would recommend that he changes the bolts. Engineers are paid to design things that will perform within certain parameters. These parameter are based on untold hours of testing and many years of accumulated experience. If you exceed these parameters you have to accept the responsibility for your actions. BMW is a quality product and we should maintain in a quality way. Link to comment
Eckhard Grohe Posted August 19, 2006 Share Posted August 19, 2006 To all of you torquers that use the yet uncalibrated grunt. A humble missive. Grunts are very variable. I can only begin to guess at what factors would effect the strength of a grunt. First, we need to have an agreed to unit of measurement for the strength of a grunt. Then, we need to form a committee to study the strength of a grunt and its variability under certain factors such as: Time of day Location of where the grunts are delivered Posture when delivering a grunt Near term activities before delivering the grunt Long term activities before delivering the grunt Lunar cycles and tides Other factors yet to be identified. I think we could go for a grant from the National Research Council on this and if not we could try some Arts funding body to turn this into a comic standup routine. Time to go walk the dog. Link to comment
Smoky Posted August 19, 2006 Share Posted August 19, 2006 Since I am in Canada, I'm using metric grunts, I have no idea how they compare to imperial grunts that would be used in the US. Link to comment
JamesW Posted August 19, 2006 Share Posted August 19, 2006 Recently removed wheels for new tires and found I could not accurately torque the rear wheel nuts because the bolts would bind and cause the torque wrench to "click" prematurely. I decided the only way to get an accurate torque on these bolts was to apply just a little WD40 to the bolt heads to prevent binding. I just don't see anyway around this if the bolts bind during tightening. Grease or anti-seize I wouldn't use. Same thing happens when torqueing head bolts and it is common to loosen the se bolts and apply a little motor oil to the contact surfaces. This from a dealer. Link to comment
ShovelStrokeEd Posted August 19, 2006 Share Posted August 19, 2006 Yep, and the specification for the head bolts is that they be lubricated with motor oil. Note that the specification for the wheel lug bolts is clean, dry threads. Now, there is a hardened washer on top of the taper portion and that must also be clean. Nothing against using a mild solvent such as WD-40 on the threads and under the face of the bolt head to remove corrosion and the like, although you should probably use something like a brake cleaner afterwards to remove residue. I use a brush with stainless bristles on my wheel lugs if they show signs of corrosion and do use a rust remover followed by a flush with brake cleaner. I use that stuff in lots of places, probably going through a couple of cans per work session. Link to comment
smiller Posted August 19, 2006 Share Posted August 19, 2006 The BMW factory service manual says, and I quote: "Do not grease or oil wheel studs!" (their exclamation point.) Kind of ambiguous, but I'm going to take a wild guess and surmise that means that you probably shouldn't lubricate them. Link to comment
DavidEBSmith Posted August 19, 2006 Share Posted August 19, 2006 Jeez, Seth, haven't you learned yet that we, through anecdotal experience and Internet rumor, know much more about these motorcycles than the engineers who designed and built them? Just as I'll never understand why people who spend $18,000 on a motorcycle then insist on reusing crush washers and buying Wal-Mart oil filters to save $2, I'll never understand why people who buy BMW because of its reputation for fine German engineering then turn around, ignore the collective wisdom of those same engineers, and do exactly the opposite of what they say to do. Link to comment
millbert Posted August 19, 2006 Share Posted August 19, 2006 W-D 40 means "Water Displacer" formula no. 40.Its probably some kind of a variation of silicone.What good would that do? Threads should be clean and dry,but if you have to use something,use blue loctite.Best feel good stuff around! Link to comment
T__ Posted August 19, 2006 Share Posted August 19, 2006 W-D 40 means "Water Displacer" formula no. 40.Its probably some kind of a variation of silicone.What good would that do? Threads should be clean and dry,but if you have to use something,use blue loctite.Best feel good stuff around! Millbert, you are correct the WD in WD-40 means water displacement.. The 40 was derived from the fact that the formula was the 40th one concocted.. Twisty Link to comment
tomk99r11 Posted August 20, 2006 Share Posted August 20, 2006 So we are agreed then? It is okay to use anti-sieze or lube on wheel bolts? Just want to make sure I understand. Those engineers are really a bunch of educated idiots, right? Link to comment
Eckhard Grohe Posted August 20, 2006 Share Posted August 20, 2006 Ever heard the term 'idiot savant'..... They are your bolts on your wheels, right. Go ahead and do as you like. Have a safe ride. Link to comment
GordonB Posted August 20, 2006 Share Posted August 20, 2006 This whole thread started cause some 'grunted' while removing his rear wheel bolts. The guy before him probably over torqued the suckers If you torque them correctly you won't need any lube or anti seizee, geez, that's my 3 cents. Link to comment
Mr. Frank Posted August 20, 2006 Share Posted August 20, 2006 This whole thread started cause some 'grunted' while removing his rear wheel bolts. The guy before him probably over torqued the suckers If you torque them correctly you won't need any lube or anti seizee, geez, that's my 3 cents. I always torque mine correctly, and they are always very hard to get out because of rust. If you do much rain riding, they are going to bind. Link to comment
ShovelStrokeEd Posted August 20, 2006 Share Posted August 20, 2006 They are very hard to get out because the breakaway torque is always higher than the tightening torque. I have never had trouble getting them out once broken loose. Of course, if I am home, I use a burp gun to remove. Link to comment
No_Twilight Posted August 20, 2006 Share Posted August 20, 2006 I didn't take time to read all 4 pages because this thread is a multiple repeat but I strongly believe in lubricated threads. I've seen many wheels start wobbling because rusted or dinged threads didn't get tight. BMW recommends dry because if you put too much antiseise on you'll throw it all over the break and tire and it won't be as pirty as a BMW should be. If you really are worried about overtorquing, decrease the torque 10%, but lubrication makes very little differnce compared to a new, dry bolt. An old rusted bolt, however, makes a lot of difference. And oh, BTH, I make my living doing this type of thing in a multibillion dollar industrial facility. But you make your own decision, it's your wheel. --Jerry Link to comment
Haynes Posted August 20, 2006 Share Posted August 20, 2006 I use anti-sieze on the rear wheel bolts. I've worked in the motor trade for 35 years and having knowledge of torque values married with tactile experience, I may be advantaged over a novice but I'm still cautious. I understand clearly thatBMW recommends torques be set using dry threads and I accept all responsibilty for any variance. It would be very nice is there was an anti-rust that was not also a lubricant. Link to comment
ShovelStrokeEd Posted August 20, 2006 Share Posted August 20, 2006 If you apply the formula supplied by Russell on page 2 of this thread, by your reckining, use of anit-seize compound on the bolts will result in a 2.5x increase in the tension applied to the bolt. I wouldn't exactly call that minor. Of course, a buggered thread, if it is bad enough, will reduce the clamping force, but, if you can screw the bolt in with your fingers, it will produce all the clamping force you need when a torque wrench is applied, if you can't, well, the bolt should be discarded anyway. The lubricant won't fling either, there is plenty of room below the bolt for it to remain there and anything that comes up the stem will be sealed by the taper washer and the head of the bolt. I'm assuming people would use a rag to wipe off any excess that showed on the outside. The brake, being on the opposite side of the wheel, is in little danger of acquiring any goop, as is the tire. Centrifugal force is a function of the radius and I doubt, at no more than 2" from the center, it is enough to even reach the wheel rim at normal speeds with something as viscous as antiseize. Link to comment
tomk99r11 Posted August 20, 2006 Share Posted August 20, 2006 My comment was tongue in cheek, which I would guess MOST readers would have seen. Despite direct statements by BMW in the manuals, and by knowledgeable authorities here, guys STILL don't get it about lube on those bolts is a no no. I don't use lube on wheel bolts, never have. Never made sense to do so. Ed explained very clearly how bolts hold and about torque. Yet guys still don't get it. Pretty funny acutally. Link to comment
Eckhard Grohe Posted August 20, 2006 Share Posted August 20, 2006 Didn't mean to offend! My comment wasn't aimed at you. It is just that the BBS needs to reply to someone and you had the misfortune to give me the opening for that one and I took the opportunity. We can still have a beer and laugh about it if and when meet. I am not an engineer but work in that environment and have a lot of respect for them. They have hard decisions to make and unpopular stands to take and I guess this is a case in point. I wouldn't want to lose any of our riding fraternity because of poor practices. We do have too much fun sparring here. After all if someone gets hurt because of a wheel or bolt failure it will be the lawyers who will be going after the engineers and we the consumer/enthusiast will lose. Link to comment
John Dickens Posted August 20, 2006 Share Posted August 20, 2006 Where is the "educated" part of the choice in going against manufacturer's directions? Please tell me how cars are directly applicable to our motorcycles? If you don't like the word 'educated' then call it an informed choice. I know the pros and cons of the procedure and I make my choice. We all do it to some extent. We fit non OEM pads, we try alternative tyre pressures, we use alternative spark plugs or move the fuel filter outside the tank. Every time we take these actions we are going against manufacturers directions. The reference to car wheels is particularly relevant to this discussion since the BMW RT rear wheel attachment has much more in common with a car wheel fixing than it does with a normal, through spindle, motorcycle wheel. Link to comment
SageRider Posted August 20, 2006 Share Posted August 20, 2006 So what are the "pros" of directly violating manufacturer's instructions and lubing the bolts? Link to comment
John Dickens Posted August 20, 2006 Share Posted August 20, 2006 For me the 'pros' are the certainty of always being able to remove the bolts as needed and the fact that the threads of the bolts will not become damaged by corrosion. Link to comment
KMG_365 Posted August 21, 2006 Share Posted August 21, 2006 Is this thread still alive??!! So what are the "pros" of directly violating manufacturer's instructions and lubing the bolts? Could it be like those of removing your charcoal cannister? [ducking and running] Link to comment
SageRider Posted August 21, 2006 Share Posted August 21, 2006 [ducking and running] Yep, this one shows the potential to outlast the oil and tire threads put together... Link to comment
GordonB Posted August 21, 2006 Share Posted August 21, 2006 But will it outlast the reuse crush washer threads Link to comment
Eckhard Grohe Posted August 21, 2006 Share Posted August 21, 2006 Non OEM Parts: Most time we replace them with functionally equivalent components or even functionally superior. Fuel filter outside the tank. is functionally equivalent but does have inherent risks and additional exposure to danger. I have been struggling with this one for quite a while. Non OEM plugs are usually replaced by ones of the same heat range and thread length and represent no direct treat to life and limb. Link to comment
Huzband Posted August 21, 2006 Author Share Posted August 21, 2006 I was gone for the weekend & just got to the computer this morning. Logged in to see what I missed, & WOW, 24 new responses! Very interesting the variance of opinions on this topic. I had no idea the can 'o worms I was opening when I posed the question. But as I stated before, I valued Ed & Mitch's input the most. Although many answers had much basis on pure knowledge, thiers had valuable facts that could not be faulted. So, Friday night, when I installed the wheel, I cleaned the threads with a brass wire brush, removed any remaining residue with compressed air & a rag. They went in easily with fingers, & I tourqed them following Haynes manual two-step procedure. I then spent the last two days exploring 500 Miles of N. Floridas best country roads, with quite a bit of "spirited" riding. Thanks again for everyones input, it's what makes this a great place to hang out. Oh, & BTW, I LOVE my new Pilot Roads! Link to comment
John Moylan Posted August 21, 2006 Share Posted August 21, 2006 ... I'll never understand why people who buy BMW because of its reputation for fine German engineering then turn around, ignore the collective wisdom of those same engineers, and do exactly the opposite of what they say to do. .....probably because, and I don't believe this for a moment, and have absolutely NO proof of it, BUT, the guy who did the bolt spec sits beside the guy who spec'd the FD bearing. He of course is in the cubicle next to the guy who, when his electronic engineering tenure came to and end, overheard the accounts guys in the canteen giving out about the price of ABS servo's seeing as they only do 1 simple job anyway, jeez wouldn't you think they (i.e. engineering) could justify the cost with an extra task seeing as they're on the bike anyhoo......., auf Deutsch, naturlich....... Needless to say that electronic engineer subsequently got a job-for-life in the brake dept. Or so he thought....cue: look at TEVES thread .....but it's o.k., on overtime he had a go at design as they were a bit short in the car dept....and came up with the trunk design on the 'flame edge' 7-series. On foot of that rip-roaring success, he got to do the whole Z4. Ah yes, progress indeed.......... 'discuss!' Link to comment
Recommended Posts
Archived
This topic is now archived and is closed to further replies.