Either system has its pros and its cons. Both for the bearing design, and for the frame mount system (i.e. the thru axle).

Thanks, Dragos - some good points. Cheaper "low-end" parts usually have more material than absolutely necessary. Instead of designing, testing and machining for minimum weight, they err on the side of caution (and lower production costs). So if I were to hack a hub and convert it to cartridge bearings, I'd go with a low-end one. So, not just for the cost-saving reasons, but because they might have a better chance of lasting after some machining. However, with those low-end hubs costing just a few dollars locally, I think it's simpler and cheaper to buy a new cup and cone hub, than to try to modify a damaged one to cartridge bearings. Regarding bicycle bearing "seals" - they are dust protectors really. Proper seals, that really prevent any moisture or dirt from entering need to be double, with some space in between, and with their contact with the metal always lubricated (so they'd be leaking a small amount of lubricant constantly, in order to preserve the seal and prevent anything entering the bearing from the outside). That takes a lot of room, and adds weight, so it's not very practical for the cycling industry. So both cup-and-cone bearing dust protectors and cartridge bearing "seals" are there to stop small rocks and larger grains of sand from entering the bearings, but they do allow water and finer dirt to enter them - the dirt intrusion being the nemesis of bike bearings and the main reason why bottom headset bearing lasts shorter than the top one, especially on off-road bikes without mudguards. And yes, cartridge bearings are more of a hassle to clean and re-lubricate, compared to cup and cone bearings that are designed to be serviceable. Here's a bikeforums .net discussion on a DT Swiss rear hub: www.bikeforums.net/bicycle-mechanics/1245022-dt-swiss-freehub-chain-slap-what-am-i-doing-wrong.html My "pearls of wisdom" are in reply #34. Long story short - it's 101 of poor engineering (in my opinion), poor design, which can't easily be compensated for even with the highest quality materials and machining. Bearing choice is not the problem there, but their position on the axle (too far inwards, leaving too much of the axle unsupported). Shimano has had their own blunders and mistakes. The point of all this drivel is that the cycling industry is run by marketing, not engineering. Major manufacturers have big advertising budgets, but their design choices are not always good. Thinking out loud: Opening and servicing a cup-and-cone hub lets you know (if) it's in good condition (no pitting) and then you're good for 5000 km. Without any service, Shimano hubs can go for about 20,000 km. Now, 20K without service results in pitted cups and cones, so you'd have to re-lace the wheels with some new hubs, but they won't break suddenly. Cartridge bearings are more difficult to open, clean and inspect. And they cost a bit more if you wish to "preventively" replace them, before any binding or play is noticeable.

Short answer: UN-300 is quite good. Explanation: When considering bearings (and mechanics in general), to me it helps visualize it all as if it were made of rubber. Stepping on a pedal creates some deflection in metals. Cup and cone bottom brackets used to be made to a very high quality (nowadays I can't find any good ones easily). But even with them, a common mistake was setting their preload so low, that they roll easily using fingers to test for smoothness. In my opinion, it's better to set them to spin a bit less freely - like UN-300 is set when the cups are tightened to the specified torque. NOT make it spin roughly, just not as easily as possible, i.e. not stop adding preload as soon as any play is gone, but make it a quarter of a turn more. Then, when a load is applied, there is no clearance in the bearing, the preload remains, which is an optimal setup. P.S. I've switched completely to cartridge bottom brackets. Shimano square taper ones last for about a decade. Still sticking with cup-and-cone hubs, but for bottom brackets, I've been happy with the cartridge models, and I welcome having dozens of overhauls per year fewer, since all the family and friends' bikes come to my garage. :)

@@BikeGremlinUS Thanks for tha quick and thorough reply! What you say makes sense, and Shimano does invest plenty in researching (engineering) their parts, not just in advertising them. Indeed, sealed BB's have a very long life, and free of maintenance too. Not having to fine tune the BB and headset (C&C ones) encourages me to maintain them (and all of the bike) more often :P. I have a 90's mtb which had "needle" bearings on the headset, but replacements are too hard and/or too expensive to get a hold of. Seems like top notch technology though. Anyway, thanks again! Cheers!

Bearings, as long as they are not problematic (severely worn or binding) should not make a measurable difference. A high level of fitness, high quality tyres, aerodynamic clothing and riding position make a 1000 times bigger difference (exact calculations depend on the particular bike, but it is close to literal thousand if not more). So, unless we are talking top-competition time trials and similar, don't sweat the bearings type. Relja

@@BikeGremlinUS yes I ride competitive. All the other things are taken care off. Aero clothing and tires. So I see you share the same perspective of Hambini that due to angular contact. Loose ball bearings are NOT faster compared to bearings. Some KZfaqr and articles says that loose ball bearings are faster. Thanks for re assurance that sealed bearings are faster

@@colecoleman1499 depends of exactly which sealed bearings you’re talking about in which hub and the same goes for cup and cone. I would say from my experience a good quality and well adjusted cup and cone will spin with less friction compared to an equivalent sealed bearing hub. If it’s outright speed you’re talking about then that’s what counts. Mainly though it’s the quality of the bearings and the fitting, and how much drag is generated by the freehub.

My new Shimano cartridge hubs are brilliant.

I svaka cast na video materijalima samo napred

Da ne bih lupao napamet - povoljne cene, znaju reći šta je najbolji odnos plaćeno-dobijeno za bicikl (da se ne kupuju superjaki, za velike brzine okretanja): www.kuglager.rs/

Whenever I get asked to recommend upgrades, my first reply, question to be more precise is: What is your current system lacking? I.e. what are you trying to improve?

@@BikeGremlinUS i wanna make the bike more efficient and les gears. little bit lighter. u make me think to keep going with the old BB. thanks for your reply Sir

I love this tool for considering different drivetrain setups and gear ranges: www.gear-calculator.com/?GR=DERS&KB=24 It's very intuitive to use - hope it helps you make the right decision for your use.

Suscripción o plomo :)

Each have their pros and cons. In my country, Shimano cup and cone hubs are the only ones that are available (and they cost a lot less than good quality cartridge hubs). The problem is that spare cones for the Shimano hubs are next to impossible to source. So it sucks if you miss the maintenance intervals, or don't set the bearing preload properly (so cones get pitted). For those who prefer 36 spoke wheels, it gets even more difficult to source decent cartridge bearing hubs. So, despite having the tools to easily change cartridge bearings when needed, I have no wheels with cartridge bearings. Relja Edit: Cheap cup and cone hubs by Quando are widely available for a few dollars here. They feel rough even when new. But they do last for a long time with regular maintenance, and they don't cause noticeable drag when mounted on the bike. Regardless of the hub quality, fresh grease (in sufficient amount) and proper bearing preload are very important. Well noted. Even Shimano XT and similar high-end hubs come with too much preload from the box, so if that's not adjusted before riding, bearings get pitted very quickly.