tendency

Hey all - I've got a Suntour Sprint cartridge hub and I'm stumped how to get one of the sides off it. I've unscrewed and removed the axle however the other end remains stuck on like this:




How is this end removed? As you can see I've got the other side off no prob and removed the seal from the cartridge:




Thanks!

sch

Most likely everything is press fit into place. You need to devise a method of applying pressure to the part you
want to remove, in this case the threaded cylindrical nut. You could use the axle for this by threading in from the
other side and protecting the end with nuts, tapping with a soft hammer or piece of wood to extrude the nut.
Then you should be able to pop the bearing cover off and this should give access to the bearings for either
clean and lube or further extrusions/tapping out, whatever works. Bunch of youtube videos on various
methods to remove sealed bearings from bicycle hubs.

Andrew R Stewart 

IIRC the "cone" as seen in the first image is a threaded sleeve that fits within the cartridge bearing. The second image shows the sleeve removed, as well as the bearing dust shield removed.

I believe if you thread the axle into the sleeve and tap the free end of the axle the sleeve will be "forced" out of the bearing. The fit should be a snug sliding one, not an interference one like the bearing's fit in the hub shell likely is.

These are very nice freewheel hubs, perhaps the nicest design that still uses a common threaded axle. Well worth maintaining. Do be careful in the reassembly and final bearing end load though. With a threaded sleeve supporting the bearing's inner race one can easily end up with too much preload and not feel it if the ball tracks are still smooth. But in time the excessive preload will lead to pitting sooner then it should. With radial contact cartridge bearings as very slight end play, after the QR is tightened, is generally considered the proper way. Andy

tendency

Thanks Andy a re-thread and tap got it out.

Another question for you: after opening the cartridges there was alot of rust on the bearing races. Even after a thorough clean and re-pack after re-assembling there's still a little 'crunchiness' when I spin them - and this is even with no load on the nuts. I have a perfect set of cyclone hubs too which are absolutely glass smooth and like-new so I know these sprints should be the same when they're 100%. Do you think the rust has destroyed the cartridge bearings? Can these be replaced?

Thanks again!

Andrew R Stewart 

The bearings most certainly can be replaced. Yes, rusted ball contact surfaces can and do make for a rough spin. (And a rant here- these bearings are "sealed" by so many people's reference yet water did get inside and cause issues. Just showing the seals are not the assumed final word that so many think they are when buying stuff). On the seals that you removed you should be able to see a bearing number, something like 6001 2RS. This code will determine the OD, ID, width and seal type of the bearings. It is best to match all specs. Also know a dimensional and seal spec is not the same as the grade of the parts. There are fairly low cost bearings and expensive ones of the same dimensions but differing qualities of tolerance and manufacturing.

I suggest doing some homework of how to remove and install cartridge bearings before replacing them. A bad method can ruin cheap and expensive bearings before they ever see a mile of use. Andy

tendency

Great thanks for the help & info Andy. I'll do some research and then replace the cartridges.

davidad

My old Suntour front hubs use 6001 2rs bearings. They are not a tight press fit and are easy to remove. To adjust the bearing the method is to take out the slack and then loosen the nut 1/4 turn. There will be a little to no play at the rim.
I use this tool if the bearing is a little tough to get out. :Enduro Cartridge Bearing Puller Tool [BBT-105] | Maintenance - Dan's Comp (danscomp.com)