jens wrote:
@BW_Tri wrote:
Once you figure out that the installation sucks, rather than bashing Cervelo, you can change the subject line to "My mechanic / I suck at installing BBRight" You can blame the installation and the 3 different bike mechanics involved with my bike. And all the other hundreds, or thousands of people who have posted about problems with the BBright/PF. Or you can realize the problem is a badly flawed design philosophy.
Insuring that two sets of bearings,~7 cm apart, are lined up absolutely perfectly within 10ths of a millimeter is a very high precision task, that should be the responsibility of the manufacturer. Cervelo has pushed that responsibility and the quality control of it onto the consumer.
With the old threaded BBs, the two sides absolutely had to line up perfectly, or the cartridge wouldn't screw in. And the manufacturer couldn't sell the bike. With BBright, they don't need to line up. And from what the mechanics tell me, they often don't (you may have just been lucky with your bikes) But that's up to the consumer to discover...... later. The bike will work, but it will creak and the BB bearings will wear out repeatedly.
The only people I've talked to who have had BBs last more than a year had to install something like this:
http://www.bbinfinite.com/products/bbright-30mm?variant=9864593283
Why? Because it's essentially like installing your own threaded BB shell. Which is what the manufacturer should have done in the first place. If you think that screw type is the answer, just ask how many power /ultra torque problems there are out there when the BB has not been faced before installation.
Threads can easily be cut out of line and we have all seen them and dealt with them.
That is why there is a whole line of BB's made to fit into misaligned threads by having one side with no threads that just interference fits.
The faces of the BB becomes just as critical to BB as the frame mold for pressfit.
Hard to face a carbon BB.
The threaded Shimano cartridges had terrible life compared to loose ball bearing types.
That is nothing to do with types, just the quality of the bearings.
The pattern I see is that some mechanics/ shops have never ending problems with BB's, some don't.
Says more about the mechanics than the equipment to me.