[Closed] Changing frame bearings - any tips?

According to Whyte i should use some Locktite on for insertion... which surprised me in honesty as i would usually have used a smidgen of grease.

No don't grease the frame! The bearings should be tight against the frame. (Interference fit would just push the grease out?)

Take your time. I'm no expert, but get the correct tools.

Locktite might be frame dependent but I never use it unless there was some sort of issue.

New bearings go in the freezer until 30s before you push them in.

According to Whyte i should use some Locktite on for insertion…

What sort of loctite? If it's a bearing retainer they're suggesting then you'll have all kinds of fun the next time you come to change them

Depends on the frame, some are dry, some are greased, some use a retaining compound. Normally depends on the fit and materials. Some frames use different fits in different locations.

Small amount of grease to ease them in.

I've always used just a small bit of grease applied to the bearing. Never even considered locktite. Freezer tip works well.

Loctite 638

apply
a small amount of Loctite 638 to the outside diameter of the bearing and to the inside bore of
the mating component

apparently.

If they are steel bearings in an alloy mount (obviously the most common combination), then I would generally apply gentle heat to the mount as the expansion of the two metals is different and this effectively loosens the bearings and makes them easier to push out without them falling apart. It's very easy to overheat and damage frames, but rather conveniently, 100C appears to be a good temperature for this so dousing the mount with boiling water from the kettle prior to pressing them out is very effective, and quite safe for the frame. I wouldn't repeat this when inserting new bearings, however, as you don't really want to get them wet, but you can freeze them instead if you need. Personally, I've never had to do this as a light smear of grease and the right tools generally seem to work.

I've never loctited a bearing into a frame (with the one exception of a creaky BB30!) and wouldn't do it routinely for frame bearings as I'd always have half an eye on the next swap when I'm faced with trying to remove a bearing that I intentionally glued in two years before! It's worth bearing (hah!) in mine that manufacturers' instructions are often created around longevity (i.e. they don't want the bike to come back to them for maintenance) rather than actual serviceability, so even if they specifically stated that they were originally glued in the factory, I'd think twice before I did it myself.

638 is bearing retainer so they definitely aren’t going anywhere

if your using bearing retainer then you need a method of applying heat to the bearing (not the frame) to get it out. Not fun.

Ive often wondered how im going to do this on a carbon frame. Im going with grease.

Haven't you got a small parts diagram for the frame that tells you what each bolt/ bearing needs and the right torque? Eg anti-seize for bearings and bolts and some critical bolts with threadlock. No grease anywhere - none of this is moving against a surface.

Get someone else to do it.

the problem i find howsyourdad1 is that half of teh people who say they can do it dont take as much care or have as much skill as i do.

Worst bike maintenance job ever

Get @andybrad to do it.

the problem i find howsyourdad1 is that half of teh people who say they can do it dont take as much care or have as much skill as i do.

Sounds arrogant, but you're not wrong. I remember taking my old Pivot in to an (unnamed) LBS for bearing replacement. They kept it for two weeks before returning it to me and, only at that point, telling me that they "couldn't source the correct bearings, so we repacked them with grease instead". Charged me a stack of labour and, unsurprisingly, they were grinding again two months later. I bought some tools, ordered the correct bearings online, taught myself how to do the job and have never had to take another bike in for bearings since then.

Haven’t you got a small parts diagram for the frame that tells you what each bolt/ bearing needs and the right torque? Eg anti-seize for bearings and bolts and some critical bolts with threadlock. No grease anywhere – none of this is moving against a surface.

I've got a diagram with torque setting but doesn't have anything else.
I'll most likely put a bit of loctite on the bolts anyway.

Get someone else to do it.

I could do, but where's the fun/learning experience in that?
I figure that if I can build 4 bikes from a pile of bits & maintain them I should be able to change some frame bearings.

For me -

-Try not to hammer bearings in, unless you really have no other option, buy correct tools instead
-I'd only use loctite on bearings if the bores were oversized/worn
-freezing bearings is a good tip, as above
-grease if you want, makes no odds really
-pop seals off of new bearings and pack with mobil222
-take your time

that's cool OP, it's just not a job i particularly enjoy. Enjoy!

-Try not to hammer bearings in, unless you really have no other option, buy correct tools instead

I've got the correct tools.
Picked a couple of these up the other week:

So hopefully I should be OK and not have to revert to hammers and sockets.

I would refrigerate rather than freeze the new bearings, just in case of brittle fracture issues (tbh you shouldn't have much issue with the new bearings).

Hot water from the kettle is worthwhile on any bearings that are being naughty as above (assuming al frame)

I changed my Yeti bearings a few times, even produced a more detailed instruction doc than the Yeti one that was available at the time, got requests for it from all over the place.
Yeti said to lightly grease the outside of the bearing - so as someone said above - depends on frame and manufacturer's instructions. If they say loctite, that's what I'd use.

Alloy frame just use a thin smere of grease around the bearing face to help the bearing seat home smoothly
Carbon frames use a thick chain oil like much off wet lube
Wipe off excess
The kinetic frame bearing tools are fantastic but always cover the face where the tool sits with a couple of layers of masking tape
I personally use some old inner tubes cut in the right size circles too especially on Carbon frames
Those manufacturers suggesting loctite are the ones who usually have squeak issues from shonky Taiwanese manufacturers and you only need a drop in one place and a hair dryer is usually enough to break it free but it's not something I personally recommend.

I've put bearings in freezer and parts like rocker plates in boiling water before hand. They just pop in...

I learnt how to do it after a lbs managed to fit some bearings so bad that they sat proud of the frame slightly as they had carved a sliver of the alloy bore out as they were being driven in at an angle....

Took them out, refitted and would never let anyone else do them again. Though with the 11 bearings I recently changed on the Jeffsy I had to remind myself of that resolve.

Some frames I've had said to use 638 and others a small amount of grease. I just use what they recommend personally.

My main advice is just to be methodical and stop the second a bearing starts to go in at an angle and begin again. For taking them out I've used heat, gentle taps around the bearing edge (if you can get to it) and plain gentle persistence! Lol

Oh and never do it if you are in a hurry and need the bike urgently.

I would never tap a bearing in. I use a bearing tool or make one up from bolts, washers and sockets. To pull out a blind bearing either a purpose made puller or a modified rawlbolt.

Most bearings are designed to run freely at speed so don't have much grease. Frame bearings rotate slowly by comparison, and a little more smooth friction doesn't matter. So I pick out the seal with a pin and pack them full of sticky waterproof grease then replace the seal.

I would never tap a bearing in.

Absolutely. Proper tools make life way, way easier and this is never more true than when doing frame bearings. I've ended up with a box full of proper tools, modified odds and ends, threaded bars, washers and assorted bushings and it's the difference between a job that takes all evening, and one that takes 10 minutes:

One big advantage of proper presses is that they line the bearings up properly, so they have much less of a tendency to go in at a wonk than using sockets and washers, so I'd always recommend that people get them if they can, at least for their most common bearing sizes.