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Buellistic
| Posted on Tuesday, November 11, 2008 - 04:57 pm: |
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"i" did in 1963 in Anderson, Indiana at the Harley-Davidson Dealer and again in 1965 at the FORD Dealer in Norfolk, Virginia ... |
Scott_in_nh
| Posted on Tuesday, November 11, 2008 - 04:59 pm: |
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Ok John, thanks for clearing that all up - trust me I am an easy going guy too and have nothing to prove, but prefer to understand the truth! That said I am still confident that I am correct, and for whatever it is worth I queried 2 mech engineers at lunch. They both ride and one has done a fair amount of auto and bike mods over the years. They both concur that a longer extension with more twist still transmits the torque setting when the wrench clicks. So let's give it a go; I'll offer one last token of my point of view: We'll assume, for simplicity's sake, that one end of the extension is on a bolt, and we're torque-wrenching away on the other end. Agreed (I think we agree that if we're comparing two torque wrenches, the torque is split evenly between them. I'm still not sure why you think I said one would click first, but, I digress) not sure what you mean here, but let's let it go for now So, we start torquing, and the extension begins twisting, along with the bolt tightening, agreed? Agreed And then the wrench clicks. We've just inputted 20 foot-pounds of torque, according to the wrench. So, we let off. As we're letting off, the extension untwists. It's giving us back our motion (which is some of the force we just put into it). Agreed? NO, this is where I have a problem. Torque does not require motion, that is I can apply a twisting force to something and not have it move, but the force is there. If it does move or twist, I have done work and yes moved energy into the extension. Sure I can release the handle and the extension untwists, or I can remove the socket end from the bolt and release the same amount of energy from the other end of the extension. At the point of "click", in our example, we have: Input torque PLUS whatever torque is stored (twisted up) in our extension is our total torque. So our click is: Total torque (20 ft-lb) = input torque + stored torque (in the extension) So, when we let off, the "actual" torque on the bolt head is input torque MINUS the stored torque that was in the extension (because the extension twisted, and not the bolt). Some of our total torque was lost in the twisting/untwisting of the extension, which means that if our desired torque was 20 ft-lb, we're now somewhere under that. While you do put energy into the extension the amount of torque at both ends must be equal or the extension is rotating. The energy in the extension, as you point out, is not passive. To stop it from unwinding, you must continue to place 20 ft/lbs of torque on the end of it. In order for it to not rotate, the other end must resist with 20 ft/lbs of torque in the opposite direction. Unless you can dispute the above, nothing else matters. This is why I suggested researching "torque-sticks". This is the Exact principle they operate under, except they're calibrated. They absorb enough torque that they can't transmit any more than what they're rated for, regardless of the input force. (I think they're a piss-poor substitute for a torque wrench, and would weld them into art if I had a set, but that is how they work) This is (Going back to OP land, as intended) also why HD spec's engine oil, not anti-sieze, not assembly lube, not graphite, not butter, but clean ENGINE OIL, for use on head stud nuts. If you torque them down dry, then the stud absorbs some of the torque, and "springs back" when you're done twisting, and the various other lubricants (which ALL have their place, just not here) have differing coefficients of friction, and thus offer skewed torque results (And I've seen this proven, too. If you have the Snap-On digital torque wrench, try it out the next time you have your heads off.) I agree with using the oil as recommended to get the correct torque setting, but have a different explanation; Without oil the bolt stops turning and you are twisting the bolt (just like the extension) instead of stretching it. When the bolt untwists, it will be at a lower setting. The oil allows the bolt to continue to turn until it has the proper stretch! |
Buellistic
| Posted on Tuesday, November 11, 2008 - 05:01 pm: |
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The one and only thing "i" like about spoke wheels is they are easy to static balance on the bike with solder !!! |
Jstfrfun
| Posted on Tuesday, November 11, 2008 - 06:29 pm: |
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Coats solid state 700 w M/C wheel adapter. It clamps onto the tire with two arms NOT the rotor. The arbor is much smaller than the axle thus the use of the cones to center the wheel on the arbor, but the arbor does not spin the wheel, the arms do. No John sometimes you are succesfull at baffling with Bull shizzle, but not today. This is what I do...just tires. The rear wheel with the buffered hub cannot! be balanced togeather, I've tied and failed every time, it's just not stable. Buellistic, I'm sure the romans used a simple method to balance the wheels on there chariots too but in this century we don't do it that way anymore, except in some situations on heavy equipment or duallys. And yes I'm old enough to remember those machines that rolled under a lifted wheel and spun the entire assembly, hub, drum, wheel and tire. But thats not the way it's done any more. |
Buellistic
| Posted on Tuesday, November 11, 2008 - 07:06 pm: |
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Jstfrfun: MECHANIC verses technician Balance wheel(complete)on bike/balance wheel on machine ... MECHANIC shifts tire(balance dot)to balance, only use weights if has too ... technician balance on machine, adds weights ... (Message edited by buellistic on November 11, 2008) (Message edited by buellistic on November 11, 2008) |
Jos51700
| Posted on Tuesday, November 11, 2008 - 08:11 pm: |
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I've tied and failed every time, it's just not stable. Just because you failed at it doesn't mean it can't be done. I've done them for years that way. Like I said, Empirical observation at work. CBR600RR - a random selection, and also the first one I picked. Item 7 insures that, when all the rear wheel bearings and spacers are torqued together, there is no uncontrolled motion in the sprocket hub.
Wheel balancers without arms use the brake rotor to secure the wheel. The arm attachment is a new development, and an unnecessary one for most motorcycles. For you saying they "MUST" be balanced clean, how many have you done? I've done thousands on the machine I pictured earlier, with rotors, and cush drives (where applicable). So you're saying that Motorcycle Wheels "MUST" be done clean, i.e. with no rotor or cush drives, right? I still want to know: Everytime you get your wheels balanced, they pull the rotors and sprockets? |
Jos51700
| Posted on Tuesday, November 11, 2008 - 09:59 pm: |
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Scott- (Like, where'd this wheel balancing discussion come from?) I agree with this statement that you made: While you do put energy into the extension the amount of torque at both ends must be equal or the extension is rotating. However, in the example of the twisting extension, one end is moving. So, to me, the force is not equal because some of the force at the wrench end is being expended due to accomplishing work. I'm going to try the ultimate test tomorrow at work (Feel free to try it at home, but not without your parents' permission! ). Using a beam-type torque wrench on a clean well-oiled fastener, through a 12" socket extension, I will torque a fastener to a given amount. (I'm aiming for something I can torque to 100 ft-lb's, but it depends on what I can find in the shop). Then, I will remove the extension, mark the fastener, and have a witness observe (For redundancy. Also, the witness probably despises me as much as some Badweb members seem to, and so will not skew results in MY favor) any bolt rotation that takes place as I re-torque the fastener to the same amount. This would be best accomplished by a Snap-on Techwrench, but that will have to wait 'till Friday when the Strap-on dealer comes by. If the bolt moves after an equal indicated torque is achieved, can we agree that the extension provides a lower actual torque than what is indicated on the wrench? If the bolt does not move at equal wrench settings, then I will admit defeat, and that I am wrong, and that I know nothing of physics. Also, if the bolt does not move at equal wrench indications, I will go above previously indicated torque, to see if the extension somehow increased the torque applied (although I think we're all in agreement that that cannot occur). Does this seem fair/scientific to everyone? The actual calibration of the beam wrench should not matter, because we're only comparing it to itself. |
Preybird1
| Posted on Wednesday, November 12, 2008 - 02:05 am: |
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Me to thread! jack!! Ahh to my experience i do my own tires by the way!! On a car mag machine! and if it is a major brand name really good quality i have never balanced a tire yet, And i have test drove and commuted on said tires at least 2 times unbalanced no vibration! All were clean! Not sure it makes a difference I swear you said Balance wheel(complete)on bike/balance wheel on machine ... On bike what? Sorry jos51700 please clarify i think you typ'od no way to balance on machine. I think i am misunderstanding. |
Littlebuggles
| Posted on Wednesday, November 12, 2008 - 02:19 am: |
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Huh? (Message edited by littlebuggles on November 12, 2008) |
Littlebuggles
| Posted on Wednesday, November 12, 2008 - 02:23 am: |
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Well it has nothing to do with balancing wheels... but I'll go ahead and say thanks here for the chin fairing PB1. Sorry for the thread jack |
Blake
| Posted on Wednesday, November 12, 2008 - 06:48 am: |
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If a well calibrated torque wrench reads 20 ft lbs, you could have an extension from here to the moon and the nut/bolt would still be subject to the same 20 ft lbs. You'd have to twist the wrench about a million revolutions to develop that 20 ft lbs, and the extension would need to be stabilized to prevent it from buckling, but extension length has no effect on the torque transmitted from wrench to bolt/nut. What the extension does absorb is energy, this would be equal to the amount of twist (from one end of the extension to the other) times half the max torque developed; it's half on account of as the extension untwists, it imparts on average half the torque on it's way back to a zero torque condition Avg = (T+0)/2 where the twist is also zero. This is the same for a linear spring where F=KX (force equals spring rate times displacement). For torsion that formula becomes T=Kq (torque equals spring rate times angular displacement aka twist), with the clarification that "K" is the spring constant or spring rate, which is different for different springs and has units of LBs/IN for linear springs and FT*LBs/Rad or FT*LBs/Deg for torsional springs. So if your extension went from here to the moon and it took a million turns to develop 20 FT-LBs, the energy absorbed by the extension would be... 10 Million Foot Pounds. And the spring rate (K) would be... 20 FT*LBs / 1,000,000 revs / (360 degrees/rev) = 0.0000000556 FT*LBs/Deg (aka 5.56E-07 FT*LBs/Deg) or... 20 FT*LBs / 1,000,000 revs / (2p rad/rev) = 0.00000318 FT*LBs/Rad (aka 3.18E-06 FT*LBs/Rad) or... 20*12 IN*LBs / 1,000,000 revs / (2p rad/rev) = 0.0000382 IN*LBs/Rad (aka 3.82E-05 IN*LBs/Rad) Fun stuff. (Message edited by Blake on November 12, 2008) |
Blake
| Posted on Wednesday, November 12, 2008 - 07:10 am: |
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When trying to arrive at an empirically based conclusion, statistics and accuracy are paramount. For your test and any conclusion drawn from it to be meaningful, you'd need to repeat it at least a dozen times for each case and then take the average results while also quantifying the statistical characteristics of the sample data, meaning variance and mean and such and tossing any anomalous data. You are also dealing with relative magnitudes (torque and nut rotation) so you'll need very sensitive accounting of actual torque applied and nut rotation achieved. Rate of rotation may also be a factor, so you'd need to accurately measure and control that as well. It's a great idea though. If you are careful to replicate conditions equally for both cases, you should learn stuff. Also, and I'm sure you are all too familiar with this, rule one in torquing a nut or bolt, when torque begins to approach the desired value, never allow the nut rotation or bolt head rotation to stop until that desired torque is achieved. This since static friction is significantly greater than dynamic friction. Imagine the extension from here to the moon and you accidentally stopped the nut turning at 19 FT-LBs, but due to static friction being so much greater, it takes 23 FT-LBs to break the nut loose and get it turning again. The highly energized extension is going to impart that 23 FT*LBs of torque on account of it would take backing off some 3/20*1,000,000 = 150,000 turns to get the applied torque back down to the desired 20 FT*LBs. |
Jos51700
| Posted on Wednesday, November 12, 2008 - 07:54 am: |
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Blake, we'll see how our test turns out! (I still have faith in my "theories") PB1, I've never said anything about balancing ON a bike, I believe that was one of my detractors. Reason for no on-the-vehicle gravity balancing lies in brake-rotor drag, and wheel-bearing drag (from grease). Most gravity balancers use itty-bitty dry roller bearings. |
Scott_in_nh
| Posted on Wednesday, November 12, 2008 - 08:59 am: |
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John, i am interested in what happens in your experiment, but fear that things will not be as repeatable as they need to be. Blake thanks for chiming in! Scott |
Jos51700
| Posted on Wednesday, November 12, 2008 - 12:24 pm: |
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I'll try to be as scientific as possible. I'd rather be wrong and err on the side of caution, than ignorant! |
Jstfrfun
| Posted on Wednesday, November 12, 2008 - 03:46 pm: |
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In initial assembly the tire is only aligned with dot to stem, no weights. My practice is to align then balance for true. Must be that Coats sells different machines in Misery than they do in the rest of the nation, but until they make the adaptors available for the new 775 model the M/C adaptors for the current balance machine operates as stated. John, the rotors are bolted to the hub...not cleanable...only the buffered drive w sprocket. Maybe physics just isn't the same in Misery. Does your toilet water spin right or left? |
Reepicheep
| Posted on Wednesday, November 12, 2008 - 03:50 pm: |
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I think it will come out fairly consistent. Do it with and without an extension with the same torque setting (where you will get a nice little cluster of nut final resting spots), then change the torque setting by 20% and repeat again with and without the extension (which again, will give you another nice cluster of final resting spots, in a new location). You will see a big change going up 20% in torque, and no change with and without the extension. Unless your extension is made of boiled noodles or balsawood. |
Jos51700
| Posted on Wednesday, November 12, 2008 - 04:07 pm: |
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The rear wheel with the buffered hub cannot! be balanced togeather, I've tied and failed every time, it's just not stable. It's perfectly stable, centered, and balance-able when the inner spacer is in place, and the arbor is tensioned. As shown, the assembly is just as rigid and concentric as it is when mounted on the bike.
In fact, in this photo (A rear wheel from my own FZR600 two-stroke), the wheel was balanced without the cush-drive hub, and achieved a neutral balance with zero weights. (The brake disc was installed, because it's needed to prevent wheel rotation on the arbor. I'd have a photo for illustration, but the batteries died in my camera). When the cush-drive was installed, and the wheel re-spun, you can see the net result. An overall imbalance of 1/2 ounce. On this particular bike, that's not significant (top speed: 65mph), but the faster you go, the more critical wheel balance becomes. Obviously, the drive hub (and sprockets, and rotors, NONE of which are factory balanced, because, as the picture shows, balancing is typically performed, in motorcycle world, as an assembly) affects assembly balance. I've seen some go as much as 1.5 ounces out by adding the drive hub. This is the same basic machine that I've seen in every single bike shop I've ever been in, from Seattle to Daytona (and at MMI Orlando), from Milwaukee (Uh, in the Harley-Davidson University classrooms, where factory-trained techs get that training) to Texas. In fact, I've yet to see the monstrosity you posted in use by ANY shop. No John sometimes you are succesfull at baffling with Bull shizzle, but not today Clearly, I'm not Bull"shizzling", and you can apologize when you man up a bit. Edit: The above statement is not called for. My apologies to JstFrFun, and anyone else offended. (Message edited by jos51700 on November 12, 2008) |
Preybird1
| Posted on Wednesday, November 12, 2008 - 07:20 pm: |
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UPDATE HERE: Ok i rode the shit out of the bike to make sure the head bolts are ok! And its running very well the new exhaust valve is a little more tappy than i like....But i suspect it will get less noisy as it wears in. Now i need to reset the tps and run the ecm spy and it should be good to go. (Message edited by preybird1 on November 12, 2008) |
Jstfrfun
| Posted on Wednesday, November 12, 2008 - 10:35 pm: |
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Congrats bird,time to ride south for a weekend, I'll buy you a beer...or two! |
Preybird1
| Posted on Wednesday, November 12, 2008 - 11:31 pm: |
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Love to but the girlfriend got to fightin with the lower tenant and we all got evicted! Got a month to find a home, Maybe a rain check though. I forgot how fast and fun this bike is. |
Jos51700
| Posted on Thursday, November 13, 2008 - 07:48 am: |
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I've done some testing with various torque wrenches, bolts, and extensions, and the results are.......................Inconclusive? Torquing a new, clean, oil-lubed large-flange bolt, with multiple click-type and beam type wrenches, and marking the flange, showed to me that, for some reason yet to be determined, no method or combination provided consistant results! I don't know why (Yet), but every combination, with extensions, without, repeatedly torqued up to a different spot. This included repeated torquing with a given combination before making any changes. Even using the beam wrench to unscrew the bolt provided inconsistant UN-torquing results and turning torques. I'm not sure if the bolt was junk or what. Please note, none of these were MY wrenches, and the bolt was from a Kawasaki. I'll retest this weekend with my tools and a different set of fasteners. |
Blake
| Posted on Thursday, November 13, 2008 - 08:09 am: |
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Excellent findings which agree with industry convention. This is why no important structural connections rely solely on torque as an adequate indicator of bolt preload. The ones that do use torque, don't rely upon it alone, they either have a lot of extra margin built in or utilize very expensive, high quality, tightly toleranced fasteners and also wrenches that are calibrated daily for torque versus bolt preload. Why the variance in your results? Not all bolts and nuts are created equal. Rolled threads are much superior in fit and finish to cut threads. Harder alloys will retain surface finish better than softer ones. Some cut threads are much smoother than others. Roughly cut threads will provide a lot of opportunity for initial wearing in. Find some nice new high quality high strength fasteners, socket head cap screws for instance, and try again. Also, be sure to put a high quality hardened washer underneath the nut so that when it turns it doesn't gall the plate/part which it is fastening. Just a plain 1" thick steel plate with a standard sized hole (1/16th over size of bolt) would be the best medium to use for such an experiment. This in order to eliminate flexure and possible out of plane deformation of the clamped part(s). Welcome to engineering 101. There is nearly infinitely more complexity to engineering than most folks ever imagine. Taking science theory and applying it to the real world of imperfect materials, tolerances and uncertainties in loading and support/boundary conditions is what engineering is all about. Fun stuff. (Message edited by Blake on November 13, 2008) |
Blake
| Posted on Thursday, November 13, 2008 - 08:17 am: |
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The biggest failure of most engineers is not in their science, but in their lack of imagination to foresee challenging even dangerous issues. Been there, done that. Who knew anyone would use lifting slings that were half as long as specified and afix them in teh worst possible fashion contrary to instructions. Ductility is good. |
Reepicheep
| Posted on Thursday, November 13, 2008 - 12:33 pm: |
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It would be interesting to mess with the torque settings on the wrench and crank them up until your "cluster" moves measurably. That will let you know what percentage noise you are currently operating in... |
Jos51700
| Posted on Friday, November 14, 2008 - 05:58 pm: |
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Well, after a visit to a local calibration center, I am proud to admit that I was flatout WRONG about torquing through an extension!(See, it happens) |
Jstfrfun
| Posted on Friday, November 14, 2008 - 06:49 pm: |
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OMG! |
Buellistic
| Posted on Friday, November 14, 2008 - 07:18 pm: |
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S!!T, it happens !!! Read more Tech. Books ... |
Skntpig
| Posted on Friday, November 14, 2008 - 11:09 pm: |
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31*F in Hell right now. |
Preybird1
| Posted on Saturday, November 15, 2008 - 02:15 am: |
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What? I got 34?f here snow soon, Jonesin to ride! To much torque scared i make spill. Could ride but am moving so no time to enjoy a brisk cold ride! |
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