Hollowtech II safety check

[@BikeGremlinUS]

To clarify: In terms of axle diameter (24 mm), material (steel), crank attachment (with enough preload) and failure mode (for the non-top-tier-super-light models axles break usually when they are worn from busted bearings), Hollowtech II is probably the least bad existing BB & crank design. In terms of crank arm design, it still has some nonsense, as discussed here: kzbin.info/www/bejne/bZaVe6yebdV7qdU Square taper axles, on the other hand, fail in the spot between the crank arm and the axle, and that is highly impractical to regularly check - as explained here with photos: bike.bikegremlin.com/10123/unsafe-cycling-patents/#3.2 Edit: Yes, square taper bearings last several times longer than Hollowtech II, that is an advantage, but I'm not comfortable with that BB patent for stuff that isn't commuting on separate bike lanes (i.e. no climbing hills in traffic, bombing down hills off-road and similar). Other modern 2-piece crank designs (SRAM, FSA and others) are basically a workaround Shimano's patent and not optimal (in terms of axle diameter for one, at least in my opinion). It is one of the silly things about capitalism, but that's what we have to work with (I heard that Park Tool company has trademarked the blue colour for tools - go figure...). :) P.S. I suggest using the BikeGremlin forum for any questions or comments, since KZbin is a bit buggy when it comes to notifications and later search: www.bikegremlin.net/ Relja

[@carlosgaspar8447]

not to worry, the hollowtech bearings have plenty of friction by design. if you can break a square tapered axle before the bearings wear out, then it's bragging rights.

[@BikeGremlinUS]

@@carlosgaspar8447 They break due to material fatigue, not for being too strong. It is a known problem - see the link above for the pics and more details.

[@carlosgaspar8447]

@@BikeGremlinUS yes, but by then the bearings should have been changed which would avoid the wear and tear on the spindle.

[@imrevadasz1086]

​@@carlosgaspar8447There are various square taper BB designs where you can easily swap just the bearing cartridges. E.g. by white-industries or the Specialités TA Axix BB. Specialités TA even dates to sell a Titanium square-taper spindle. And many square taper BBs are known to work for many years before the bearings are worn. So square-taper spindle long-term reliability is a serious issue to consider.

[@BikeGremlinUS]

If we're talking about square taper axles breaking, they don't break from bearing problems, generally. They break because of the fatigue when transferring loads, at a place where the cranks are mounted (usually at the left crank, because that side sees both bending and torque transfer at the same time (when you press on the left pedal to turn the chainring on the right side). Bearings of square taper BBs are hidden from much dirt intrusion inside the frame and, thank to the spindle being relatively low diameter, can be big enough. They last for years and years on cartridge square taper BBs without any servicing. Square taper BBs don't have problems with bearing durability. They are outstandingly good in those terms.

[@leosergio06]

Yesterday, my Shimano hollow tech crank axel fractured while out on a ride. Exactly as you describe, I was at the top of a climb, out of the saddle, when all of a sudden, the weighted crank gave way. Fortunately, no injury. Just an Uber ride and walk home. Once I realized what had happened, I remembered your video. Thank for your channel.

[@BikeGremlinUS]

Glad to hear it ended well.

[@oreocarlton3343]

Your insights are phenomenal! One of the few channels on youtube that goes into depth about everyday working mans or budget ridigng mans components.

[@JamesMcCarthy-jb9jr]

Good idea, thank you.

[@impaledface7694]

I do similar checks on my adjustable loose square taper bb, although I don't remove the chain since it's kinda obvious. Haven't tried it for 2 piece cranks, but it makes sense and should improve the life of crank spindles. Since I have seen pictures of them getting worn down where the bearing is.

[@sloprun]

I noticed the chain is oily and dirty. Have you considered waxing the chain like Oz Cycle has demonstrated? My wife and I just went through the process on our bikes and it makes a world of difference, preserving the cassette and chain rings, and extending the life of the chain.

[@BikeGremlinUS]

Glad to hear it works for you. I haven't been very happy with chain wax. This has been my experience: kzbin.info/www/bejne/lXPEgZl-prZle8U Relja

[@sloprun]

@@BikeGremlinUS I watched your video. However, Oz Cycle has a system for using hot wax and PTFE powder that works very well. There is the initial time to thoroughly clean the chain and hot wax it with the PTFE mixed in. However, the once every 180km rinse and wax is very quick. The big benefit is the superior lubrication that extends the life of the chain and cogs and chain rings. I encourage your viewers to watch.

[@CreativeFishDesignsCharlotte]

thanj you sir

[@_kicaBo_]

I'm watching the video, my wife walks by and asks - is this one of our guys? :)))))

[@BikeGremlinUS]

"Malo nas je, al' smo govna!" :) Da se našalim malo na svoj račun, valjda se niko neće naljutiti. :) Relja

[@_kicaBo_]

@@BikeGremlinUS Komentar naravno nije išao na tu stranu, ali tvrdnja je više nego tačna :)

[@MangoJim90]

🤩👍🥳

[@cyclingjoezone]

Good video, thanks.

[@taichihead42]

Square Taper was the Best

[@BikeGremlinUS]

I’d refer to the pinned comment regarding square taper. It has its pros, but also cons. Relja

[@Svenson612]

@@taichihead42 If you weigh more than three figures and jump, no, unless you test the ground closely. Regards.

[@BikeGremlinUS]

Square taper breaks from fatigue - not from a high impact. Though yes, stronger, heavier riders that ride up hills (or sprint often) are more likely to push past the fatigue limit of the steel axle.

[@drunkdriver]

Thanks for the information