Broken Bearings: Shimano Alfine WH-S501 8-Speed Hub Teardown 

Thank you very much. Could not assemble the most inner part because everything fell into my hand during disassamble. Now there is hope ;-)

I can see why Shimano does not sell parts. No one would be able to reassemble that correctly. Interesting video. Love see how stuff works.

Excellent video. Thanks for taking the time to explain the internals. You obviously have a strong background in either machining, materials, and/or metallurgy. Looks like I won't be considering an Alfine for any belt-drive bikes I might consider.

Hi Catus, Thanks for the video. I have watched a number videos and check the Shimano manuals to try and understand the bearings. How I understand it now is the wheel (hub) spins on the axel bearing on the brake side and on the large bearing on the drive side. The axle bearing on the drive side is for the input shaft/clutch assembly that rotates at a different speed. What causes the free-wheel friction problem is when the cog fits too tight against the dustcovers. (I have a Nexus hub and hope the bearings last!) Your feedback will be appreciated, regards.

The most difficult and critical part is getting that cone nut adjustment correct otherwise it will loosen up, or to tight distroy the bearings

Great video thanks. I've had a nexus 8 on my touring bike for 8 years covering the whole coastline of Spain where I live. The bearings have finally given up but I have a new complete part to replace at my local bike shop. Problem, I want to keep the shell and just insert the complete internal gearing but the shell has a small bearing cassette inside it that I need to replace. Can I buy that little bearing cassette keeping the shell or am I going to have to buy a new shell and have a full wheel rebuild? Thanks Frank in Altea southern Spain.

If someone ever tries to convince me that internal gear hubs are more simple than the derailleur setup i'll show them this video...What a nightmare...

Interesting video Cat, but that's some crazy intricate design.

Actually, snapring removal is a test. Anyone struggling with it needs to turn in their shop apron and leave the work area! Apparently, the "seals" on that hub don't actually "seal" at all!

Yeah my friend it helped me, thank you

I have commented on your previous video. I think the 3 lobe drive sprocket should have been dished out. I suspect the failure of the race was due to the free play you were experiencing because the chain side plates were dragging on the face of the hub. It might be worth replacing the race and flipping the sprocket. Regards, Philip.

Brilliant ! min eis earlier, and the sprag clutch is completely rusted = junk. Notice that the large bearing uses the hub shell as the outer race, that is a disaster as there are no seals and water kills it.

thank you that helped a lot

Could you plese elaborate on excessive friction on that big bearing? You think it's because of all bearings being adjusted at once on the left side? I think it's the same in every other IGH. Maybe the cones were just overtightened? It's weird though that only this one got broken while all the others seem ok. Btw here in Poland, you can easily buy almost every of those separate parts, for rather reasonable money.

The new digital hubs are excellent.

This was helpful thanks! What did you do with the parts? I need one of those small cogs... would be happy to buy off you

Hi, Catus Maximus. Just wondering if I can buy your alfine 8 if you still have it. Thank you.

А он собрал потом все обратно?

Allways puncture finger with this freaking snap-ring... 10x!

Now I really know about a machine I had no interest in! Good job Catus. Ride it away! Come look at my aircraft.Pipers and Cessnas and Moonie oh boy!

Great video really overly complicated for a bicycle and then not to last is disappointing.

Getting the Snap Ring From Hell off is the easy part. Getting it back on is why it gets it's own moniker. How can Shimano after years of making Internal Gear Hubs not design the S.R.F.H. to accept a pair of snap ring pliers? Any other brand has an easy to install/remove snap ring but Shimano seems quite content for it's customers to endure Ice Pick Injuries struggling with this.....and then to not make parts available. Fortunately there are many other Internal Hubs coming to meet the E Bike demand for stronger hubs.

I really, really wish you guys would clean them first before you disassemble!

Làm sao dịch tiếng việt cảm ơn

Snap-ring from hell is a pussy-cat - thanks :-) Top geezer - pronounces 'Alfeenay' correctly...

I only wanted to learn how Alfine works, but these graphic videos explaining it are just confusing and make no sense, seeing this video explains everything. Now this part was not broken, all that was broken was the big bearings and it looks easy to replace them. Broken is broken, unrepairable. Shame...

I see pigmat

It's not pronounced "Alfeenay", it's just "Alfeen". Thanks though, good video.