SHIMANO BB-RS500 BSA-Innenlager (Lagerschalen) // Tiagra, Sora

Product Information

However Shimano advertise that SM-BBR60 & BB-R9100 use 'small ball bearings'. This is not necessarily a good thing, in that smaller bearings are weaker. However there are more of them. Still it would be reasonable to assume that the RS500 will be DIFFERENT in durability from the other two, but not necessarily worse. From what I've seen with balls you have the issue of ball material Vs race material (probably best if they are both the same - stainless is probably not an advantage), then ball size, then lubrication, then sealing. It is possible there is a difference between the sealing on the different models however it doesn't seem to be something Shimano promote Cranksets with 30 mm wide spindles won’t fit into frames with BB86, or BB90 BBs, but with correct BB some can be made to fit into threaded frames. Note: crankset for mounting on externally screwed in bearings, with a hollow axle 24 mm in diameter, is compatible whichever manufacturer produces it. So: Race Face X-type, FSA MegaEXO, Truvativ/SRAM Giga X Pipe (GXP), Campagnolo Ultra Torque – they are all compatible with Shimano Hollowtech II standard, so only Hollowtech II will be named in tables and remainder of the post.

Crank designs that will fit: BB30, BB386 EVO, standard 24mm external-type, Specialized OSBB, BBRight If you have any questions (or additions and corrections), please use the BikeGremlin forum’s compatibility section: Once you’ve narrowed down your search by “mounting standard,” the last thing to consider is weight, color, and grade. Crank designs that will fit: BB386 EVO/BB392 EVO specific, standard 24mm external-type (can be adapted), BBRight, BB30 (axle width dependant),the genesis brand are owned by Madison, who are also shimano importers for the UK. I would imagine that someone in shimano has said 'this is the future' or something. Probably it saves about 50p in manufacturing costs too. Eyebrox wrote:It's the usual range of Shimano hierarchy options. The more you pay the better the quality.

Other notes Analogous to BB30 above, but uses pressed cups (with identical bearings) for relaxed manufacturing tolerances OSBB (Road) I think it’s more about the simplicity of the manufacturing process,” says Drew Guldalian of Pennsylvania-based custom builder Engin Cycles. “Boring out a [standard] BB30 is not impossible, but in my opinion it’s an unrealistic task from a manufacturer’s standpoint that needs to do something to make money. As stiffness is directly tied to cross-sectional size it’s no surprise that, theoretically, BB386 EVO has the most to offer, with both the added shell width and diameter that many frame-makers yearn for.From the outset, Cervélo introduced BBRight as an open standard that anyone could jump onto. While it seems to make good engineering sense, however, other bike companies have been slow to come on board.

This performance boost comes with no other changes to basic dimensions: the left bearing stays in the same spot; the aluminium cup is simply replaced with carbon frame now. And since the bearing’s in the same spot, the lateral position of the left crank isn’t changed at all, so Q-factor is also unchanged. Your feet are in exactly the same place as before.” The tolerances are not too different but the way they’re measured is. They both have the same needs for concentricity and placement relative to the frame. The threads are at a disadvantage in that they need to be machined from both sides and have a hard time sharing a centerline, whereas our OSBB is machined from one side all at once — and round holes are easy to measure.” Threadfit 82.5 is not really a new standard in that it is compatible with BB86 cranksets and bearings. BB shell width 86.5mm road, 91.5mm MTB. Other widths may be named according to shell dimensions: 89.5mm, 104.5mm, 107mm, 121mm, 132mmBB30 and PF30 cranksets won’t fit frames with different BB shell standard, because their spindle will be too short.