Bottom Bracket Selection Guide
Bike Creaking? Solve that PressFit mystery today
In this bike service tip video, Gary and Wes host a primer on PressFit bottom brackets, covering basic functionality and construction as they compare and contrast the BBInfinite system and the other bottom bracket products on the market.
Hi I'm Gary, product manager with BBInfinite. Hi I'm Wes, product engineer and together we are the team that's bringing you BBInfinite precision cycling components. What is a bottom bracket? Well in layman's terms a bottom bracket is that part of your bike where the crank goes. And it needs to spin smoothly and if you just spin it by hand while the bike has no load on it whatsoever, no chain attached it should spin you know 20 times and that's just the assumption. Well the dirty little secret is currently in the bicycle industry since the advent of the press fit bottom bracket the fact is it doesn't spin that smoothly. Press fit is bearings pressed into a cup which is then squeezed into a frame for retention. The bottom bracket is all about the bearings. The vast majority of bottom brackets out there today run what's called a radial contact bearing. The relationship between the various components that make up the bearing is critical and the three things you never want to do to a radial contact bearing are - first, you never want to radially compress the bearing. If you take a one-size-fits-all cup and press it into a hole that's too small, you introduce what is called "radial compression" causing drag on the bearings which also causes creaking bearing longevity issues it also means that you have a rotational performance that is being sacrificed. The second thing you never want to do is side load a bearing. When you side load a bearing, you deflect the inner race causing friction making the bearings hard to turn. Lastly, you never put bearings in a place where they are not properly retained or supported or unitize so most of everyone out there right now is looking for a solution to some of these problems and that's what BBInfinite is so as Wes just talked about the problems. What is the BBInfinite solution? Well, the solution is the One-Piece design. You no longer have those two pieces that are getting pressed in independently. By going in with one piece we are able to get the same retention as the other guys, but we're squeezing it only half as hard. And what this alleviates is radial compression. Which is the number one thing that literally drags a rider down and saps wattage. But at the heart of the BBInfinite module is the real solution - and that is the Tru-Drive sleeve. This is what maintains the proper relationship between the inner races so that the side loading that Wes was talking about is completely eliminated. And the team mechanics are going to appreciate - and do appreciate how much easier BBInfinite is to install the one-piece design slides right in and it is easy to service you service the inside of the bike you don't have to just take a hammer to the bike to remove the bearings anymore so initially we designed it around just trying to get rid of creeks and increasing the longevity but what we heard back in a resounding chorus right away was the athletes themselves felt faster sure they were glad it wasn't creaking anymore but one guy even told me you know if that was this much faster and my bike creaked even worse I still wouldn't care and the best thing that for me as a product developer is when I have the captain of a race team get a video on YouTube of one of our crank spinning in the very bike that she's supposed to be racing and she says I want that it's very gratifying
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