joedab

I've tried searching the web for this topic, but so far haven't found anything definitive. The issue is that I newly installed a Campagnolo Record bottom bracket into my frame (it was to replace another spindle and cone bottom bracket because of shell threading issues on the non-drive side, but that's another topic). After tightening down the flanged drive side retainer very well, I moved on to tightening the non-drive side with a decent cinch and when then feeling the spindle, it had a new crunchy sort of feeling, with resistance at every certain fraction of a turn. I brought it into my LBS to get an opinion and it was concluded that I over tightened the adjustable retainer and that those should really only be tightened enough to not come loose, maybe only 5-10 ft-lb. I wasn't totally convinced and the manual for the BB says nothing in the way of torque specs; it just says tighten the sides, and I am wondering if this is something mechanics implicitly know to avoid damage to the bearings? One other thing is the retainers came with a stripe of yellow compound on the threads, and even though I greased the threads, I am wondering if this was a sort of thread lock so as to compensate for very gentle tightening?

fietsbob

Which era of BB are you talking about ? Square taper spindle cartridge types I dont think the mounting rings compress the bearings .

(thats the last Campag Components I have used, personally )

Torchy McFlux

Was your bottom bracket shell faced and chased before you installed the cartridge?

https://www.campagnolo.com/repository...cket-06-06.pdf

hueyhoolihan

IME, most modern BBs i have used are fine when i can just start to feel the bearings begin to tighten when turned (non-drive side). usually i back it off a half turn or so and leave it at that. i can still tighten down the drive side as hard as i want to.

FBinNY 

If you're talking about a square taper cartridge BB, of the 2001 or so era, the dealer is right. These are sometimes sensitive to the compression loads of the rings, which is probably why Campagnolo departed from past practice and pre-treated whese with a thread compound.

The carbon shell cartridges were prone to binding when overtightened, whereas the Chorus aluminum shell version was just about immune. Don't know if this was a tolerance or material properties issue, but it was what it was.

joedab

Is it really that easy to ruin the bearings with a snug turn of the wrench? I am still not sure of a proper torque and if mechanics are careful to tighten them ever so slightly (that said, caged bearing BB adjustable cups are this way, but they also have a lock ring). Granted I know bottom brackets are different, so yes it is a square taper and here is a picture.

reptilezs

you frame shell needs to be chased with piloted taps. cartridge bbs can take plenty of torque. only the plastic left cups need a lightly lower torque value. shimano has moved away from the plastic cups now too

rydabent

There is a big difference between sealed bearing BBs and cup and cone BBs. But the big thing is I have a running argument here about the fact of "preloading" bearings. I contend there are few bearing in machinery that should be preloaded. None on bikes. Simply put preloading causes bearings and races to deform. It leads to early failure. If you "preload" how do you know how much you are preloading. IMO proper adjustment means adjusting down to almost no clearance.

Back to your question, if you felt the bearing "crunch" when you turned the spindle by hand it was too tight. Did you ruin the bearing probably not. Just back off to zero clearance so the spindle turns free.

fiataccompli

I'm resurrecting this thread because after installing a number of these Campy square taper Record BBs, I had what the OP described for the first time while doing one yesterday evening . Spec says 51 ft-lbs. With 51 on the drive side I can only get around 20-30 on the non-drive before it binds. Guess I wanted to comment here to see if this is considered common....and how has the lesser non-drive side torque worked out for others. Thanks

fietsbob

AFAIK you are just pushing the bearings together more at the outer edge if there is a shoulder on the axe that is a fixed width.

In Shimano's UNxx the left side sleeve stabilizes the cartridge , the right side is the tightened one ..
that is why Plastic L side was adequate .

FBinNY 

I was Campy's east coast service tech when this BB was active. Yes it was a common problem with the Record BB with a carbon center sleeve. It was extremely rare with the Chorus BB of the same design but with an aluminum sleeve. We never identified a cause, but most likely a tolerance issue.

fiataccompli

Thanks! I got it to a point this morning where I am comfortable and of course it helps that I can do it myself so I don't freak out if something comes undone on the shakedown ride....perhaps with other bottom brackets I was lucky or something it turns out in my workshop I had three good record bottom brackets and one chorus but I wanted to use the record.