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This post is to document what I did to solve an issue with a clients new 2012 Cervelo R5 VWD. This issue was specifically related to the BBright bottom bracket. You do not have to search very long to find a list of folks who have had issues with their BBright. All that I want to share with you here is my approach to this problem and what I did to resolve it.
This 2012 Cervelo R5 frameset was purchased from a local Cervelo dealer and was assembled by the same dealer with Shimano Dura Ace 7900 using a Rotor BBright bottom bracket for Shimano Hollowtech 2 cranksets. From day one, the owner was getting a loud clicking/knocking noise coming from what appeared to to be the bottom bracket area. He returned it to the dealer where he purchased it from to get it looked at and fixed. He took it out for ride after getting it back only to find that the noise was significantly worse. He took it back a third time and mentioned to them that he read on a Cervelo forum that the fix was to use Loctite 609. After he picked up his bike from the dealer for the third time, he rode it and said that the noise was worse than it ever was. At this point, I was called.
I always take initial test rides on bikes that are making unwanted noises in order to get a baseline. This situatuion was no different. I didn't take long at all to hear the noise. It happened in most of the gears as well as both in and out of the saddle. I was also able to feel movement thru the pedals... There was no mistaking that there was a problem in the area of the bottom bracket.
I removed the non driveside crankarm and found damage to both the Rotor cup and the crankarm. While removing the driveside of the crankset, the driveside Rotor bottom bracket came out at the same time and remained on the spindle. This was a concern for me because of how easily it came out of the bottom bracket shell. I was more like a slip fit instead of a press fit. I then removed the non-driveside Rotor cup from the frame and found what appeared to be Loctite 242 (blue medium strength threadlocker) that was applied between the bottom bracket shell and the cup. I was both surprised and not surprised to find this knowing the Cervelo dealer that swung and missed three times with this bike... As an aside, Loctite 242 is a threadlocker, not a bearing retaining compound. It has little if any retaining capabilities. This is basic stuff here folks and a major league half-assed attempt...probably would have been better to use nothing rather than 242...unbelievable. If you're curious, this is the only Cervelo dealer in the CLE area.
Since there is absolutely no way to check the roundness of the shell or the squareness of the faces, I had to assume that they were "within spec". I hate doing this...even with a frame that has a MSRP of $4900US. Moving forward, I advised my client to get an Enduro PF30 bottom bracket along with Enduro BB30 to Shimano Hollowtech 2 adapter kit.
Plan of attack:
After receiving the Enduro parts and testing the fitment of the cups in the bottom bracket shell, I talked to the owner of the bike to share some of my thoughts and ideas about how to approach this. I then called someone in customer service at Cervelo on the owners behalf to see what Cervelo had to say about this. I was told that I should use Loctite 680 (high-strength, for larger gaps) along with the Loctite 7471 Primer so that I wouldn't have to "deal with the issue in the future"... I also asked if I should leave the bearing press in place overnight to allow it the retaining compound to cure square in the frame. He said that I should instead imediately install the crankset and let in cure with the crankset installed so that we wouldn't have to "deal with any bearing alignment issues". Well, this gave me a ton of confidence in Cervelo's quality control and there products in general... Did I mention that this is a $4900 frameset?
Armed with this info, needless to say, I was full of doubts, frustrated, and had very little confidence in doing what I was suggest to do by Cervelo, I did more research and then I made a call to tech support at Loctite. I shared my concern using the 7471 primer on the composite shell and the Delrin cups as well as I wanted to be certain that I will be able to remove the cups from the frame in the future without damaging the structural integrity of the shell itself. After a long conversation, the tech suggested using Loctite 7649 primer instead of 7471 as well as Loctite 609 retaining compound instead of Loctite 680. This was mainly because the 7471 primer is specifically for metals, not composites and Delrin. He recommended using the medium strenght 609 retaining compound if the gap is more like a slip fit. He said that the 680 would be somewhat of an overkill and wasn't certain that removal wouldn't damage the shell. I felt good about this approach regarding keeping the cups secure in the frame. Now onto the BBright adapters...
In order to make the crankset work, I needed to modify (i.e. machine down) the non-driveside reducer/spacer. While I liked the quality of the Enduro aluminum reducer/spacer for the driveside, I wasn't thrilled about using the other Enduro reducer/spacer on the non-driveside. This was mainly due to the fact that the OD of it was recessed into the cup next to the bearing. I thought that it was better to have an overlap with the bottom bracket bearing cup. Fortunately, the adapter made by Wheels Manufacturing does exactly that. Additionally, it's a engineering grade machined Delrin, so it could easily be modified on the lathe at the off-site RogueMechanic machine shop...
Armed with this info, I called my client and laid out my plan of attack. He gave me the approval to move forward.
I installed the Enduro cups after having to notch out a small area of the NDS cup so that it would clear the cable guide insert that was protruding into the shell without the retaining compound. I wanted to do a dry fit first. I then machined down the outside surface of the NDS adapter to the needed dimensions. I then took the bike out for a quick test ride to see if what I did reduced the noise. I knew that I was heading in the right direction with this fix when I couldn't get any noise from the bottom bracket area. Needless to say, this was good news.
After removing the crankset, adapters, and the PF30 cups, I prepped all of the surfaces and then applied the Loctite 7649 primer to the bottom bracket shell inner surface as well as on the mating surfaces of the cups. I then applied the Loctite 609 and then pressed the cups into the frame. As per Cervelo's advice, I installed the crankset and allowed it to cure overnight.
I took the bike for a quick test ride the next day and it was as quiet as a church mouse. At this point, all that I had to do before returning the bike to my customer was to align the rear derailler hanger that was wasn't even close to being in proper alignment and correct the chain length...yes, this shop couldn't even get these basics right.
The rest of the "story":
I delivered the bike to my customer and he immediately took it out for a several hour ride. I told him to not baby it and to call me after the ride to give me a report. I received his call later that day and he gave it two thumbs-up. I got a second call from him a couple days later right after a very hilly local race. He reported that it was quiet and smooth and that he placed first in the race.
I was satisfied with the results. If I had to point a finger at the cause of this issue (besides that the bottom bracket doesn't have any threads...), I would have to say that it's 50/50 bottom bracket ID and Rotor bottom bracket cup OD specs not being as precise as they should be. The whole BBright is what it is. I think that it's sad that someone who drops more than $8K on a bike had to spend several hundred dollars more for me to make it right...this is just me being honest. I think that bike shops and their mechanics need to be held more accountable and to much higher standards. If you are not going to do something right, don't do it at all. I shouldn't complain because bike shops seem to be some of my best "customers".
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