Rear sprocket install disaster

[skipperT]

1 hour ago, petshark said:

I was just looking into that, yes. I'm still pretty new to wrenching so learning as I go along. That seems a good option. I can also try to source a hub from a crashed MT09 (I suspect they crash more often than Tracers and it's the same part)

I just learned this the hard way. I've been using the torque wrench on a lot of stuff because I thought that way I could develop the feel, but if it's all too tight I might as well forget it. Talking about the axle, that should be 150 Nm but that is also way to tight according to many so I did 100 Nm. At least I read about that before I ruined the aluminum wheel alignment block.

Torque values gave me peace of mind but that's all over. I'll try to go back to developing a "feel", it's what I always did before. But working on a motorcycle is serious business as there's a lot less margin for error so I tried to follow the book.

Could we perhaps make a sticky post with community torque settings and/or warnings for high torque values? If you're like me and don't have the experience it sucks to never be sure if you're going to strip a bolt or if it might come loose and potentially cost you your life. That's an obvious downside from learning these things from video's and books, I wish there was a thing like community garages over here.

There is one about torque values, I’m on a mobile otherwise I’d link it for you. 

what kind of torque wrench did you use? Because I hate to be the bearer of bad news but you definitely get what you pay for when buying a torque wrench. (I’m gonna get flamed for this ) but Plan on spending close to $100 at least USD on each wrench (double and triple for snap-on, etc) if they are of any quality. 

you’ve just learned the hard way why a good torque wrench is essential. If you’re not going to invest in a quality tool then you may as well go back to a “by feel” method of tightening fasteners (as you mentioned). I don’t agree with that when it comes to Critical fasteners, but hey I’m not the one riding your bike.  

I’ll say it again: I follow published torque specs (including rear axle and sprocket nuts) to the letter and have NEVER stripped a fastener because I own quality torque wrenches. 

you guys can disagree with me and under-torque and second guess the manufacturer values all you want, but I still say they came up with those numbers for a reason.

sorry that this has been a hard leaning experience but don’t give up one continuing to work on your bike the right way.

-Skip

Edited May 14, 2021 by skipperT

[peteinpa]

The below listed bikes are WAY more powerful then our 900. Most have #530 chains.

               Sprocket bolts           Axle

Hayabusa     43.5                      72.5

ZX10            43                         94

ZX12            43                         94

ZX14            51                         94

954RR          47                         83

1000RR        47                         83

All above in FT.LBS.

I'd be willing to bet that every one of the above axles and studs are larger than ours.

Yamaha R1:  They have the same problem as us on their forum.  Stripping axles and sprocket studs trying to torque to spec.  axle 108      sprocket bolts 72.

Suzuki GSXR's had a factory bulletin, they lowered their called for torque for the rear sprocket bolts from  67.5 to 43.5 FT.LBS.

Yamaha needs to step up.

 

Edited May 14, 2021 by peteinpa

[Warchild]

There is no way I am taking these Titanium sprocket nylocs to that ridiculously high torque value of 59 ft-lbs. Then again, I have been doing these sprocket changes on very high-powered chain-drive bikes for the best part of 30 years, and have the experience to know better. Currently with the BMW S1000XR, the Hayabusa before that, the YZF-R1 before that, the CBR1100XX Blackbird before that, and the Honda CBR1000F before that. The R1 aside, none of these bikes call for such insanely high torque values; that is how you get into trouble as poor petshark has experienced.

I will take these Ti nylocs to ~ 43 ft-lbs when I replace the factory drive train in early June. That is more than sufficient.

[skipperT]

2 hours ago, Warchild said:

There is no way I am taking these Titanium sprocket nylocs to that ridiculously high torque value of 59 ft-lbs. Then again, I have been doing these sprocket changes on very high-powered chain-drive bikes for the best part of 30 years, and have the experience to know better. Currently with the BMW S1000XR, the Hayabusa before that, the YZF-R1 before that, the CBR1100XX Blackbird before that, and the Honda CBR1000F before that. The R1 aside, none of these bikes call for such insanely high torque values; that is how you get into trouble as poor petshark has experienced.

I will take these Ti nylocs to ~ 43 ft-lbs when I replace the factory drive train in early June. That is more than sufficient.

Yes, but that’s not an OE fastener, you said it yourself that they are Ti. Different ball game and totally different scenario. 
 

-S

[petshark]

Follow up

The epoxy has locked the stud in place and I was able to undo the nut. It too is completely stripped. So again a glimpse of hope that the hub is actually not (that) damaged, seeing that the stud looks really bad and the nut had no thread left in it.

I spent all day trying to find a M10 x 1.25 nut, called at least 10 nuts-and-bolts specialty shops and none had it in stock. The same for Yamaha dealers, I even tried some Honda dealers because I found some references that they also use this fine-thread-flanged-locking-nuts-M10's. They all could order but none had it. One said they did so I went to get them and then found out home it was just a regular 1.50 thread. So I started calling Yamaha dealers further away and found one that had 2 black nuts in stock. And it works! It's on there tight and I will leave it like this for now and check it regularly.

5 hours ago, skipperT said:

what kind of torque wrench did you use? Because I hate to be the bearer of bad news but you definitely get what you pay for when buying a torque wrench. (I’m gonna get flamed for this ) but Plan on spending close to $100 at least USD on each wrench (double and triple for snap-on, etc) if they are of any quality. 

you’ve just learned the hard way why a good torque wrench is essential. If you’re not going to invest in a quality tool then you may as well go back to a “by feel” method of tightening fasteners (as you mentioned). I don’t agree with that when it comes to Critical fasteners, but hey I’m not the one riding your bike.  

I’ll say it again: I follow published torque specs (including rear axle and sprocket nuts) to the letter and have NEVER stripped a fastener because I own quality torque wrenches. 

you guys can disagree with me and under-torque and second guess the manufacturer values all you want, but I still say they came up with those numbers for a reason.

sorry that this has been a hard leaning experience but don’t give up one continuing to work on your bike the right way.

-Skip

I'm not giving up. 💪 As always, once it's fixed frustration turns into a feeling of accomplishment and I'm ready to tackle the next job. Interesting that you have no problems with the stated torque values. I wonder what else can be a factor in this; how fast/slow the wrench is pulled, and even confidence against hesitance. I have to admit that using a long wrench with the wheel flat on the ground and me keeping it still with me feet was not inspiring the most confident movements on my part. Also I did clean off some sticky grease residue with WD40 which probably lubed the thread. This could also cause over-torquing, perhaps?

On the other hand the points that the others make also make a lot of sense. I can't see any logical reason that Yamaha should have these much higher torque values while the parts are essentially the same. But they could be there for a valid reason, but that reason could have nothing to do with what's best for a bike that is already sold and out of warranty. I don't know.

One interesting thing; none of the three Yamaha dealers I talked to was aware of any issue with the torque values in the manual. All said that they DO NOT use new nuts and DO follow the manual specifications.

About the torque wrench. I agree with you. So I bought a German brand with a German calibration certificate that I am happy to share and the price was a little more than 100 dollars which was a good deal. As you can see, my set value of 80 Nm was likely a little lower seeing that 120 Nm was recorded as 116 Nm each time. I'm willing to do a test and hang 8 Kg of it if you still think it is suspect but I'm pretty confident that it was either user or Yamaha error. I could be wrong of course.

 

[JonnyB]

Just for info. At work we had an electronic torque test machine that we used to on-demand or annually check  through their range the dozen/ 15 wrenches used in our workshops. It did confirm that the more expensive wrenches, especially the click-stop setting versions that have a locking ring (like snap-on) gave the best results. Any wrench > +/-3% error was replaced. Generally, this error gradually came in at the highest settings. Basically,  don't expect a cheap / old / uncalibrated wrench to give accurate results, especially as the target settings are generally based on new dry fittings rather than the bolts you may have pulled and refitted x times.

[JonnyB]

P.S. Getting the Snap-on rep to take our torque wrenches away for factory service, calibration and return was more expensive than buying a new wrench. This is in England.  I guess it should be more achievable in U.S.

[petshark]

3 minutes ago, JonnyB said:

Just for info. At work we had an electronic torque test machine that we used to on-demand or annually check  through their range the dozen/ 15 wrenches used in our workshops. It did confirm that the more expensive wrenches, especially the click-stop setting versions that have a locking ring (like snap-on) gave the best results. Any wrench > +/-3% error was replaced. Generally, this error gradually came in at the highest settings. Basically,  don't expect a cheap / old / uncalibrated wrench to give accurate results, especially as the target settings are generally based on new dry fittings rather than the bolts you may have pulled and refitted x times.

They were replaced? Aren’t they easily calibrated with an adjustment screw if you have such a machine?

[Warchild]

2 hours ago, skipperT said:

Yes, but that’s not an OE fastener, you said it yourself that they are Ti. Different ball game and totally different scenario. 
 

-S

Nope, I would treat the oem steel sprockets the very same way - 43 ft-lbs, not any more than that

[betoney]

With as many reports of stripped  or over-torqued fasteners over the years, I am very skeptical using Yamaha's values.  Sprocket nuts are one of the few things that I use a torque wrench on but I always start at -15% of whats listed in the manual and then add just a bit more.  YMMV.

[piotrek]

I don't remember if my bike had thread locker on the stud threads (nut side) from factory, but according to the service manual it is a dry assembly. Do I see thread locker just under the nut in the photo, or is that just a bit of corrosion?

Interesting read on torquing fasteners from Yamaha here. Marine engine talk, but applicable just the same.

[skipperT]

4 hours ago, petshark said:

They were replaced? Aren’t they easily calibrated with an adjustment screw if you have such a machine?

No. 
i’ve had to replace 2 torque wrenches over the years because I sent them in to be calibrated and the part I wore inside the wrench wasn’t available as a separate part, or adjustable in such a way as to calibrate the torque wrench. The calibration company didn’t charge me and gave me a credit toward a new one but still that only softened the blow. 

I now have 3 digital torque wrenches. No more “clicker style” for me. Unless I drop them, I calibrate them every 2-3 years especially the 1/4” drive one because I use the F!$* out of that one. 

And @petshark I did see your posted sheet from your wrench, glad you spent some money. Who knows what happened in your case? Just chock it up as a learning experience and move forward. 

-S

[Warchild]

11 hours ago, peteinpa said:

Yamaha R1:  They have the same problem as us on their forum.  Stripping axles and sprocket studs trying to torque to spec.  axle 108      sprocket bolts 72.

 

Yep, I recall this now - I belonged to that forum when I had my Yamaha R1, and couldn't believe it when folks said that the service manual said to take the sprocket nuts to 72 ft-lbs of torque. I thought "YGTBSM, that can't be right". Nope, they were right, the manual said 72 ft-lbs.

 

 

Never understood why Yamaha would do this. Still don't.  I really loved that bike, I had the Arterial Blood Red version.  Got more citations on that bike than on the Blackbird and Hayabusa combined. And I only owned it 2 years - traded it in for the brand new Gen II Hayabusa in the Fall of 2007, before I got another citation and endangered my driver's license. 🙄  You can see why all discipline went out the window once you swung a leg over this baby:

 

[JonnyB]

It was rarely successful adjusting out-of-tolerance wrenches, it just moved the error up or down the scale. 

[petshark]

4 hours ago, JonnyB said:

It was rarely successful adjusting out-of-tolerance wrenches, it just moved the error up or down the scale. 

Oh I didn’t know that but I guess it makes sense for professional tools that are used daily..

Adjustments are probably still successful for amateurs like me that use it once in a few weeks (and always return to zero). I saw some videos where the results were very good. 

I suspect with light use it may just offset over time because of temperature and humidity whereas a pro’s tool will wear because of friction and compression.