2008 Forum Crossfire Re: Campy Ultra-Torque

by John Satory October 07, 2009

It all started with this thread that I started on Roadbikereview.com forum....

Hello All,

I hope that this message finds everyone well. To all who have a Campy Ultra Torque crankset/bottom bracket system, you might find this interesting...

http://roguemechanic.typepad.com/rog...nolo-ul-1.html

Let me know what you think and if you have any questions.

Thanks!

John

... and let the flames begin!!!

Editors Note: I the interest of fairness, I am including the posts in their entirety so nothing can be taken out of content.

<<<< C-40 >>>>>

You're missing a lot, John. I'm a mechanical engineer with over 30 years in the business of precision measurement, so I'll give you my explanation of how the system is supposed to work. I'll first say however, that I installed my first UT crank this spring. After 3500 miles, I've got no sideplay or creaking issues. My crank has worked perfectly all year, on two different frames.

Yes, there is a fixed distance between the bearings, but forget about the Hirth joint. It has nothing to do with the situation. No manufactured product is perfect and there is a chance that a crank could have been produced with a mistake in the overall bearing spacing. I wouldn't jump to the conclusion that this means that any, all or many cranks suffer from such a problem. There also two bearing cups in the system and either one of those could have a dimensional error. Unless you have the factory drawings to know what each component should measure, you're not going to be able to say where the problem lies. The toughest thing to measure would be the distance between the bearings, to verify a problem, but a long internal micrometer would do the job. Measuring the cup thickness between the shell and bearing contact surfaces, is one simple check than anyone with a micrometer could do. If you have several cups around, you could at least compare them for deviations.

Campy specifies that the BB shell width must be 68mm +or - .8mm. If I read correctly, you measured a nearly perfect 68.1mm BB shell width. Did you also verify that the shell faces were square with the threads? Since I don't own expensive BB facing tools, I screw both cups in until they contact a .010 inch feeler gage, then use .008-.012 inch feeler gages to search for high or low spots. Neither of my LOOK 585 frames needed facing to square the faces to the threads.

Another BB shell problem that can occur, but is nearly impossible to fix is misaligned threads. If the threads on each side are not in alignment with each other, no amount of thread chasing or shell facing will fix the problem. Thread chasers merely follow the path of the orginal threads and usually do little but remove burrs, unless the original thread was cut under low limit on the pitch diameter.

One of the confusing issues with the BB cups is the use of Loctite 222 (or not). I've bought two sets of cups this year, for two different frames. Both sets came with a large amount of a yellow thread locker applied to the threads, from the factory. I personally decided to grease the threads of the BB shell and torque the cups in place, rather than use loctite 222. Loctite should only be used on threads that are free of foreign material, so using it without removing the yellow thread locker would not make sense. Also, the yellow thread locker produces so much intereference that it is impossible to hand tighten the cups. Mine required a substantial amount of torque, just to get the cup faces in contact with the BB shell. I would not use Loctite 222 unless I knew the BB faces were not square and also had no way to correct the problem. The loctite is intended to keep the cup faces aligned with the threads, even if faces are out of square, but it won't help if the threads are misaligned. I also think a BB installed with the loctite would be far more prone to creaking, particularly if little or no torque is applied. If the loctite doesn't hold adequately, any small movement of the cup will result in a creak.

The purpose of the wavy washer is simple. It's nothing but a spring to apply a preload force on the bearings and eliminate all freeplay. If the BB width is not within the specified dimensions, then the washer would not produce the desired minimum pressure, or it would produce too much, resulting in binding and/or premature bearing failure. Of course, if there are errors in the dimensions of the crank or the bearing cups, then there could be a problem even with the proper BB shell width. There should never be any actual "freeplay" in the system. When you pushed on the crankarm and got movement, all you were doing is overcoming the spring force of the wavy washer - that's how it's supposed to work! You also mentioned a system that can't compensate for variations in the BB shell width. That's precisely what the wavy washer does. If all other dimensions are correct, then any BB shell in the specified range should produce an acceptable preload on the bearings. The reason that one spindle length can also accomodate a 70mm Italian BB is a no-brainer. The thickness of the cups is just made 1mm thinner on each side, so the nominal distance between the cups faces is the same. Get out your micrometer and compare the two types.

It seems to me that installing any amount of shims merely defeats the intended function of the wavy washer, immediately increasing the preload tension. I'd start with trying a new wavy washer, or better yet a new pair of bearing cups, that includes the washer. Install those and see if it works any better. Of course, if the crank is dimensionally incorrect, the problem will remain.

Be sure that all surfaces of the bearings that contact the cup are greased to prevent creaks. Also don't overlook another common source of creaks, the chainring and bolt area. If I think I've got a creak, the first thing I do is apply some thin lube, like Slick 50 1-lube to eliminate that area as the source.

Now that I've read even further into your posting on the subject, the more I realize you really don't understand the system and just guessed at a fix (adding shims). If you really supected a wear problem with the bearing cups or bearing OD, you should have taken some precision measurements rather than take the shade tree mechanic approach of guessing. Your fix really defeats the system and is likely to ruin the bearings, if they aren't ruined already.

There have been some reports of bearing failures on early model cranks, but changes were made at some point before '08 cranks came out. The latest bearings have plastic rather than metal cages around the balls.

Also, since you're dealing remotely with a customer, be sure the problem is not something totally unrelated like creaky cleats or a creaky saddle. I just put a new saddle on with no lube in the rail area and it's amazing how a creaky saddle clamp can sound just like the BB.

Last, I'll say that you final conclusions are totally wrong, regarding both the Hirth joint and the loctite. Perhaps you should just post your problem details and spare yourself the public display of ignorance (sorry, couldn't resist).

::::::::::: RogueMechanic:::::::::::::::::::

Hello C-40,

Thanks for your comments to my post and your experience is very impressive and valuable. Ok... be patient with me as I reply to some of your points.

If you recall, I never made a statement that all bikes with the UT system have this problem, but I am basing my theory on the fact that the majority of the bikes with the UT system do exhibit this issue. And an overwhelming majority of those are composite frames.

Your comment that no component that is manufactured is perfect. I agree, but neither are frames, specifically bottom bracket shell widths. But in this one case, the shell width was pretty darn close to industry standard 68mm. This has to be accounted for in the bottom bracket/crankset design. Additionally, it's been my opinion that Campy does not lack in the QC department when it comes to precision.

Yep... I checked the squareness of the threads... but if it was the rare case of misaligned threads in a high-end frame, binding would be apparent... I didn't observe any binding.

I'm with you regarding the use of Loctite... But I follow instructions to a T so eliminate that variable...

I guess that I'm confused about the use of the wave washer in the UT system... I agree that one of the typical uses of a wave washer is to preload the bearings... but in this application, maybe they need to supply different wave washers based on specific shell widths... I pushed on the NDS crankarm to replicate the knocking that my clients were experiencing... Again, I'm going to mention that this movement, even when compressing the NDS arm like I did, is not typical for any other system on the market.

With all due respect, I did look into the issue with the retaining clip. When the spring/clip is installed, the bearing is by no means locked into place. After measuring, I found that the drive-side bearing width is~5.88mm and the dimension of the depth of the cup to the inboard surface of the pins is ~6.42mm. That theoretically leaves us with a difference of ~.54mm. Additionally, the ability of the two pins to lock the bearing is also deficient. I have found this similar situation with every UT system, so I am not sold that it's a failure of the retaining spring/clip. I am leaning towards the chance that it's one of the factors.

I did everything short of beating my head against the wall trying to come up with a solution, and constantly came back to spacers. I have to think about the influence the wave washed would have on the bearing because it's dimensions allow for it to press on cartridge bearing "shell" or externals and not the ball bearings or retainer...

Regarding your final thought, this isn't a one time occurrence that I'm basing this on... I'm having a hard time accepting such a large percentage... well over 50%. This is not typical of Campagnolo.

Thanks again C-40 for your comments! Please let me know if you have any other questions or comments.

Edit: C-40, I just noticed your opening statement. Ouch. With all due respect, I guess that I need to have your experience to troubleshoot this issue and my 25+ years experience doesn't account for much. I'm just offering a theory and a possible solution to a repeating pattern... That's all. I didn't mean to disrespect anyone. If you took the time to read a little deeper into my posts, you will find that I take the stand more of an advocate for the cyclist than anything else. Thanks again for your insight and comments. -John

John, you may have 25 years of experience, but doing what? Manufacturing and measuring precision machined components, like I have, or just fixing bikes? Your postings are not those of anyone with a background in evaluating a problem with precision fits and clearances, or you wouldn't be so confused about how the wavy washer works and how simple it is to accomodate both 68 and 70mm BB shell widths. I took a rough measurement of an uncompressed wavy washer and got about 3mm. The washer material is only .63mm thick. I can easily see this washer having the ability to cover the specified 1.6mm range of BB shell width.

<<<<<<<< C-40 >>>>>>>>>>>>

John, you may have 25 years of experience, but doing what? Manufacturing and measuring precision machined components, like I have, or just fixing bikes? Your postings are not those of anyone with a background in evaluating a problem with precision fits and clearances, or you wouldn't be so confused about how the wavy washer works and how simple it is to accomodate both 68 and 70mm BB shell widths. I took a rough measurement of an uncompressed wavy washer and got about 3mm. The washer material is only .63mm thick. I can easily see this washer having the ability to cover the specified 1.6mm range of BB shell width.

To really evaluate the possibility of an dimensional error, you'd measure the inside to inside distance between the bearings, with the Hirth joint tightened. Then you mic the distance between the bearing faces on the bike. That dimension will be a lot less than the distance between the bearings, because the wavy washer takes up any extra space and applies a preload force. If you measured the stack height of the uncompressed washer and found it was not significantly greater than the gap between the bearing cup and left side bearing, then there is an obvious problem. The washer must be compressed by some mimimum amount or there will be undesired axial play and no preload.

You also made some pretty strange comments about the loctite process affecting the width between the bearing cups? If the cups contact the BB shell firmly, you'll get the same width as when they are torqued in place, at least within a couple of thousandths of an inch. Totally insignifcant with a large 1.6mm width tolerance.

FWIW, my carbon frames are both within a few thousandths of an inch of the nominal 68mm width, so mine is not a tight setup in the range specified for this crank. I have absolutely NO lateral play in my crankarms after 3500 miles of use, since the wavy washer is doing its job to eliminate all lateral play.

It makes no sense for some large percentage of frames to work properly and another large percentage to have problems, unless you can relate those problems to specific cases, where BB shell widths over a certain value work properly and those below a certain value don't. If the shell width was the problem, your spacer cure would have fixed it. Since the problem wasn't fixed, your guess was wrong.

Carbon frames certainly don't contribute to the problem, unless the real problem is just one of transmitting a normal sound. Aluminum frames can act like a sounding drum too.

You mentioned possible wear on the bearing OD or cup ID. The bearing race is extremely hard and unlikely to wear, so the nickel plating on the cup would be the first place to look for signs of wear. That type of wear would allow some movement at the ends of the crankarms, but that is radial play, not axial play (measured along the spindle centerline).

If the wavy washer is doing it's job, then both of the bearings should be held firmly in place against the inner faces of the bearing cups and the retainer clip will not be in contact with the bearing. The clearance between the clip and bearing won't change anything. It doesn't matter if the clearance is .5mm. If you push sideways on the left crankarm at the center (not leveraging the end) and manage to exert enough force to overcome the wavy washer, you might indeed get the arm to move .5mm to the right, until limited by the retainer clip. Once again, that's how it's supposed to work. My initial post gave the impression that the clip to bearing clearance might be a problem, but after thinking again about how the wavy washer pushes the drive side bearing to the inside of the cup, it would only come into play if a force was applied that was larger than the wavy washer's force.

When you talk about adding all these spacer and then checking for "play", were you (incorrectly) applying a force to the ends of the crank arms. If so, you were fixing one thing and checking something else.

If you apply leverage to the right or left, at the ends of the crankarms and get a lot of movement, you may indeed have worn bearings and/or worn cups. With a problem like this that's burning up a lot of shop time and producing no cure, most mechanics would just replace both bearings and cups and see if that fixes the problems. I'd upgrade to an aftermarket replacement bearing. What I really suspect is your last attempt at a fix has greatly increased the bearing preload and if the bearings weren't already cooked, they are now!

The last time I read Campy's instructions, I thought they were poor, since they did NOT (to my recollection) say anything about removing the factory applied thread locker. As I stated before, if this material is not completely removed, the cups could never be screwed in by hand and the loctite would not work properly. Perhaps Campy assumed that users would notice the loctite instructions saying that both internal and external threads must be clean and dry for the product to work.

I would leave the factory thread locker in place, grease the threads and torque new cups in place and skip the loctite.

:::::::::::::::::::::::::::::::: RogueMechanic :::::::::::::::::::::::::::::::::::::::

C-40...

Your condescending comments are a smacking reminder of why I don't visit/read cycling forums. I will try to answer a few of your questions, but remember that I have 25+ ONLY fixing bikes... so I don't nearly have the expertise and experience that you obviously have...

First a few points and some comments, then I'll be on my way...

1. I introduced this as a theory as to why this is happening to some bikes with the UT system. Never did I state that all bikes with UT have this issue. I tried to introduce this idea in a somewhat professional manner, not by saying "this sucks or that sucks...".

2. I posted this on this and another forum with the hope that I might shine some light on the situation. Do a google search, I'm not the only one who experienced this.

3. Do you have a solution to this problem? I'd be open to suggestions. Or maybe you can talk to my clients that have had this issue that is now resolved and you can tell them that it's normal for their Record or Chorus UT crankset to knock and click like it's nobody's business...

I think that you're having a hard time distancing yourself from the precision machining world and that of the cycling industry. The tolerances that you deal with are significantly more precise than those of the cycling industry.

If you go back and read what I said about the use of loctite on the cup threads, I did say that it was kinda far-fetched...

"If the shell width was the problem, your spacer cure would have fixed it. Since the problem wasn't fixed, your guess was wrong." ... Or was it? Again, go back and read what I wrote. After adding the single spacer between the cup and the shell, I added additional spacers between the wave washer and the cup internally. I suppose that I could have added those spacers to the cup frame area.... The way I see it is that's another way of doing the same thing...

Never did I say that carbon frames contribute to the problem. I stated that based on my experience the noise issue was more prevalent with carbon frames.

"If the wavy washer is doing it's job, then both of the bearings should be held firmly in place against the inner faces of the bearing cups and the retainer clip will not be in contact with the bearing. The clearance between the clip and bearing won't change anything." - C-40, you're a little confused... The wave washer sits between the NDS bearing and NDS cup seat... Please review.

"If you apply leverage to the right or left, at the ends of the crankarms and get a lot of movement, you may indeed have worn bearings and/or worn cups. With a problem like this that's burning up a lot of shop time and producing no cure, most mechanics would just replace both bearings and cups and see if that fixes the problems. I'd upgrade to an aftermarket replacement bearing. What I really suspect is your last attempt at a fix has greatly increased the bearing preload and if the bearings weren't already cooked, they are now!" I have a hard time believing that Record and Chorus bearings are wearing to this degree at 1-3k miles.... And if the aftermarket bearings have the same dimensions, what difference it that going to make in this situation? And in regards to bearing preload, the OD of the wave washer is pretty darn close to the OD of the bearings. I would think that the "preload" force is applied to the externals of the cartridge bearing and not the bearings or retainer.

Oh God, I love this one....

"Now that I've read even further into your posting on the subject, the more I realize you really don't understand the system and just guessed at a fix (adding shims). If you really supected a wear problem with the bearing cups or bearing OD, you should have taken some precision measurements rather than take the shade tree mechanic approach of guessing. Your fix really defeats the system and is likely to ruin the bearings, if they aren't ruined already." ... I seem to understand the order of assembly better than you in regards to where the wave washer is located. Again... this was my THEORY for the reasons contributing to the movement. Please explain to me how my fix defeats the system... I am all ears... or eyes in this forum. And I LOVE the shade tree mechanic comment...

"Last, I'll say that you final conclusions are totally wrong, regarding both the Hirth joint and the loctite. Perhaps you should just post your problem details and spare yourself the public display of ignorance (sorry, couldn't resist)." Maybe they are C-40, but at this point they haven't been proven to be wrong. I'll give you my weak argument regarding the loctite. But if I would have posted the problem details as you suggested, I would have more than likely received opinions and back-handed comments such as yours. Instead, I chose to research the issue and base my theory on first hand experience... But hey... what do I know, I'm just a bike mechanic but you are a mechanical engineer with over 30 years in the business of precision measurement...

Note: My intention of this post was to possibly help with this issue that some are experiencing. If you take the time to delve just a little deeper into my blog, you will see that I take the position more of an advocate for cyclists than anything. I do my best to bring some issues to light and maybe along the way, solve a few problems. But let it be known, that I have learned my lesson about cycling forums such as this one. Thanks for your time. -John

<<<<<<<<<<<<<<<<<<<<< C-40 >>>>>>>>>>>>>>>>>>>>>>>>>>>>>