My BB30 bike creaks. Help!
It's basically a daily occurrence. Someone emails me, "My bike is creaking" or "My bottom bracket is creaking" and I ask them what they've got. Once we wade through the confusion of today's bottom bracket standards we often arrive at "BB30" or "BB30A". Cool. And then they tell me they've got a 30mm spindle. Bummer.
It's a bummer because I'd rather they just ditch the 30mm crank and get a Shimano, Campy UltraTorque, or GXP crank and use one of our DirectFit modules because our BB30 DirectFit Modules never creak. Ever. And they give users mind blowing performance. But if you don't have the cash to invest in a different crank, then we've got your best-case scenario-fix right here. For those of you who think you simply must have a 30mm spindle for some esoteric performance advantage then we've got you covered here too.
To clarify, BB30 is not the same as PressFit30. BB30 calls for bearings to be pressed directly into 42mm ID interfaces in the frame bottom bracket shell whereas PressFit30 bikes have 46mm ID frame bottom bracket shells and use a housing, often plastic, with a bearing pressed in it to do the job. We're only talking BB30 in this article.
Most BB30 bikes come with 30mm spindles because that is exactly what the system was designed around, so it "makes sense". BB30 was rolled out by Cannondale years ago in alloy bikes. It's a superb economy of components from a design standpoint: bearings press in frame, crank slides into bearings, BOOM...done. And then it creaks. You fix it. A few weeks later it creaks again. And again.
To fix it we must understand what is causing it. So why is it creaking? Answer: movement. A creak, any creak, is movement. The leading cause of BB30 creaking is bearing migration within the frame bb shell during use. The bearings shift around a minute amount, resulting in the dreaded creaking sounds. Typically somebody greases the bearings to fix it. This only masks the problem, or more often, exacerbates the problem. To fix a creak one must stop these micro-movements.
So here's how we deal with a creaking BB30 bike when a 30mm spindle is in use:
Remove your BB30 crank, clean it, and put it in the freezer. Trust me, just do it.
Knock those old BB30 (6806) bearings out and throw them away. Now take those brand new Ceramitech or BBInfinite ABEC-7 bearings out of the package and meticulously clean every bit of oil and grease from the outside. Don't mess with the grease inside the bearings. We just want to degrease the outer, flat face that interfaces with the frame bb shell. Now give the frame bb shell the same treatment. Use White Lightning Clean Streak or rubbing alcohol and a clean rag or paper towel. Don't use automotive brake cleaner or carburetor cleaner, for God's sake. You'll strip the finish off your bike. Now, let it all dry. Is it clean? Good. Now soak a q-tip with some loctite 609 or VibraTite 530 and dab the fluid onto the flat outer surfaces of the bearings. Start the bearings in the frame by hand and...
What, you don't have any Loctite or VibraTite? Just ask us when you order and we'll send some with the bearings.
Now that the bearings are started in the frame by hand, make sure they're nice and square. Next, engage the dies and the press. We recommend our own Master Tool Press for this, but the Wheels Mfg. Large Sealed Bearing Press (Press-1) is good too. Just make sure you use a press that ONLY pushes on the outer race, like ours, or one that presses on both races simultaneously, as does the Wheels Mfg. one. Never, ever press bearings in with a tool that primarily engages the inner race. You will ruin the bearings as quickly as if you had struck them.
Begin driving the bearings inward. This is a critical moment. If the bearings go out of square by even the slightest degree, stop, remove the crooked bearing, and reset it squarely before recommencing your press operation. Press the bearings in until they seat firmly against the back stops or snap rings. The thin coat of VibraTite or Loctite will take it from here. Use alcohol or Clean Streak to clean off the residual Loctite. Let the whole thing sit for at least 3 hours if possible.
Install the crank with all hardware as recommended by the manufacturer. Yes, grease the spindle.
Why did we freeze the crank? We advocate this because aluminum shrinks appreciably at moderately cold temperatures. Shrinking the spindle slightly is enough to let it slide in by hand instead of going at it with a mallet. This allows the wave washer to do its job and prevents you from using the crank spindle as a drift to dislodge a bearing you just got done installing with Loctite.
So there you have it, all done and guaranteed to be creak-free for a good long while.
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