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>The pressfit junk they pushed on us was for ease of manufacturing and low cost. Consumers realized they were worse, and they started to avoid those. From what

>The pressfit junk they pushed on us was for ease of manufacturing and low cost. Consumers realized they were worse, and they started to avoid those. From what I've seen said by bike experts on YouTube, pressfit is actually superior, because it saves weight, and is (maybe) still used on top-end racing bikes for this reason. The problem with pressfit is that it requires very precise manufacturing, and apparently most mfgrs just can't make a proper round hole in carbon fiber. Threaded BBs are more practical because they allow for sloppier manufacturing tolerances. Of course, threaded is better for end users who want to do their own repairs, since it doesn't require special press tools like pressfit does.

hgomersall 3y ago
I don't believe that it's easier to make a threaded hole than a smooth hole. I suspect the issue is that if you're making a threaded hole you simply can't pretend it's good enough so you're forced do it properly in some sense.
- midoridensha 3y ago
  You can't make a threaded hole in carbon fiber at all; it's impossible. This isn't the issue. The issue (according to the YouTube experts) is that for mass-market bikes, the manufacturers have somewhat poor quality control and manufacturing tolerances (as far as drilling holes apparently). For a press-fit BB (bottom bracket), you need an extremely round hole, accurately sized for the BB to press into (hence the name). For a threaded BB, this isn't an issue, because those aren't pressed in. Those have an aluminum threaded part that's bonded into the hole; the hole doesn't have to be super accurate, just good enough for the aluminum part to fit into properly and get glued in. The aluminum part has the threads and perfectly fits the BB, and since it's machined out of aluminum at some other factory, doesn't have the problems with tolerances that the CF parts have apparently.

hgomersall 3y ago

I don't believe that it's easier to make a threaded hole than a smooth hole. I suspect the issue is that if you're making a threaded hole you simply can't pretend it's good enough so you're forced do it properly in some sense.

midoridensha 3y ago
You can't make a threaded hole in carbon fiber at all; it's impossible. This isn't the issue. The issue (according to the YouTube experts) is that for mass-market bikes, the manufacturers have somewhat poor quality control and manufacturing tolerances (as far as drilling holes apparently). For a press-fit BB (bottom bracket), you need an extremely round hole, accurately sized for the BB to press into (hence the name). For a threaded BB, this isn't an issue, because those aren't pressed in. Those have an aluminum threaded part that's bonded into the hole; the hole doesn't have to be super accurate, just good enough for the aluminum part to fit into properly and get glued in. The aluminum part has the threads and perfectly fits the BB, and since it's machined out of aluminum at some other factory, doesn't have the problems with tolerances that the CF parts have apparently.