This is a first post. I'm hoping someone one this board may be able to share some experiences with the use of Campy UT Cranks on frames with a press-fit 30 bottom bracket.
The Campy press fit adapters (68x46) have been available for a while but those I know who have been using them are experiencing both creaking and movement issues. The drive side cup tends not to stay in place but actually moves out of the shell by up to a half mm and the bb creaks and grinds. This is in spite of using anti seize and Teflon plumbers tape. The bikes in question are Ti.
PF30 was developed by SRAM and I have not heard of major dramas using the SRAM/truvativ PF30 bb's and BB30 cranks but I (and others I know) would prefer to be able to stick with a fully Campy group if possible.
It would appear the Campy pf30 adapters are either poorly designed or there is a trick to installing them that is not being freely shared?
Please note, there appears not to be an issue with the Campy BB30 adapters (68x42) - only the PF30 adapters. PF30 uses a wider bb shell without any circlip grooves to retain the bearings. The bearings in a PF30 bb are retained inside a cup.
Lots of smaller custom builders seem to be adopting the PF30 "standard" due it being easier to manufacture.
Any experiences or tips out there?
assuming the fit is good, there are other things to consider:
for both campy's bb30 and pf30 adapter cups, you have a press in cup with a skirt of a particular depth that will hold a bearing mounted outboard of the frame. the high cyclical loads applied to a crank are basically trying to pry the cups out of the frame. the fact that campy allows for some space between the left bearing and the inside of the cup (the space is taken up with a wave washer) allows the cup to start moving out.
best possible install of current parts:
i would not grease or anti-sieze the cups. leave the plumber's tape for your kitchen sink. remove the cups and thoroughly clean them and the bb shell of the frame with alcohol. being a ti frame, i suggest using a scotchbrite pad on the inside of the bb shell, and cleaning it with alcohol again. spray the inside of the shell with some loctite primer (recommended for inactive metals, both ti and aluminum count) and apply loctite 609 all around the cup skirt. then press it all together.
if it STILL walks out of the frame, repeat, but install very thin shims next to the wavy washer to remove as much of the excess space as possible.
best possible scenario: Cannondale's SiSL crank, (optional: get the 135bcd spider and use genuine campy rings to be super-pro)
HillBilly wrote:Lots of smaller custom builders seem to be adopting the PF30 "standard" due it being easier to manufacture.
PF 30 was originated to allow for less than ideal frame tolerances........and frame BB's are exposed to various demands on them during construction...........the result is PF30 relies on the use of plastic material in the hope to down play the less than idea tolerance issues.......so OK Campy chose to make the cups in a finely machined aluminum alloy......so that the resultant precision could be part of the problem (but which originates from a less than idea BB surface)....
Do you know that the frame has been finished in an acceptable (tolerances) manner?...since a frame manufacturer who opts for PF30 might be hedging that they can get away with less than optimal tolerances........."thisisatest" has some suggestions - and although I can't agree with them they are food for thought. I suggest a talk with the builder to ask the actual tolerances followed by a few checks with a caliper to gauge the actual accuracy of the BB bearing surface. If it seems acceptable then a bit of grease at all pressure points as a first measure, then if things don't work out experiment with plumbers tape and similar options until the issue is resolved....but do keep in contact with the frame builder.....and keep in mind that he/she played the "easier to manufacture" card by going with PF30.
BTW - BB30/PF30 is NOT the cat's meow...............
My next steps are pretty much in line with what thisisatest has suggested, although I am a little skeptical that loctite with actually hold the cup in place given the force that is pushing the bearing/cup out. A small Shim to take up the wiggle room will hopefully help. Failing that, I happen to have a Cannondale Si crank on another bike that I can put in by using a PF30 bb. I would have preferred full Campy.
I fear the real issue here is simply that the Campy "solution" to PF30 is not a very good one. Like tommasini and others have said, PF30 was designed around the use of plastic sleeves. Campy have used a finely machined alloy option.
I'd still be interested to know if there has been any success at all with the Campy PF30 adapters? I can't seem to find anyone who has had long term success with them...??
Out of interest, my frame is a Moots Vamoots RSL and the tolerances seem to be spot on. I can't fault the frame at all. This is a Campy issue.
I'm using Campagnolo UT BB30 (68 x 42) cup set, and am having a devil of a time with them. They just aren't tight enough in my frame (Cinelli Strato). My LBS told me they could take out the cups with their hands, not a good sign.
We've taken them out, cleaned them, tried to glue them in, and it seems fine for one ride, but shortly after it degrades again. Oh wow is the creaking loud and scary sounding.
My next attempt to fix the problem is to use an FSA set up BB30 adapter cups with a mates Rotor cranks. I guess if they press in nice and tight its the Campy cups that are the the problem, and if they don't its the frame. Either way its a shitty outcome.
If anyone has any tips I'd greatly appreciate it.
in the end i used it as an excuse for a set of THM m3 cranks much better system
another option is the newish wheelsmfg bb30-to-campy adapters. you use bb30 bearings in the frame, install the adapters, then install your campy crank. you do end up with two sets of bearings, four total. one set is along for the ride, which bugs me, but like all other wheelsmfg delrin adapters, they should be a fit-and-forget, creak-free option.
The Cannondale manual specifies a minimum of 12mm width contact area for any PF carrier to the BB socket in the frame. The Campag cups have about half this contact area and if you take away the lead-in taper on the Campag cups and o-ring groove, what's left is about 4mm of useable contact surface. Not enough.
At the moment, I've installed a SRAM PF30 bearing adapter and a set of FSA SLK cranks. This arrangement is working well.
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