Topic: wheel bearings

[crashmaster]

1972 CB750 K2. I removed the wheels to change the tires and try to clean up the rusty rims (not gonna be fun). Should I dig into the wheel bearings; do you automatically change them if they are elderly? Don't wanna fix stuff that doesn't need fixing. Or do you just re grease the existing bearings? Thanks

[madmtnmotors]

These are some very robust bearings. I don't know how many miles it takes to wear them out, but I'll wager that very few of them ever see near enough miles to physically fail. The exception would be those exposed to the elements for a very long time. I have carefully removed the bearing dust seals, cleaned, regreased, then reinstalled the dust seals. After cleaning out the old grease check for any "gritty" feel to the bearing or any galling of the ball surfaces. Pressing the bearings in and out would probably be better than beating them in and out.

[crashmaster]

I'll check them out. Thanks!

Wish I had a 55 gallon drum of Evaporust for the rims 

[Ozzybud]

Use some SOS pads and warm water on the rims.  Also you can use Navel Jellly and rinse with water.

[bryanj]

To remove wheel bearings you have to drift on the inner race which does thecraces no good at all so if you knock them out replace them.
Original bearings only have a seal on one side, i always replace with twin sealed, either rubber or steel

[crashmaster]

Thanks guys. The SOS pads with soap?

[Deltarider]

Wheel bearings can easily outlive your bike. They don't need maintenance. I have destroyed mine in the rear wheel* by using a pressured steam washer. I did this only once. Not only had I to renew the bearings soon after, also the grease in the sprocketcarrier was gone and so the drive flange had worn and needed to be replaced. The ignition was dead and it didn't much good to the drivechain either.
* The one in front still spins like new.

[jlh3rd]

be careful using naval jelly on chrome.

[madmtnmotors]

To remove wheel bearings you have to drift on the inner race which does thecraces no good at all so if you knock them out replace them.
Original bearings only have a seal on one side, i always replace with twin sealed, either rubber or steel

There are pullers that can be used to remove the bearing. It ain't easy getting a purchase inside the inner race with the spacer sleeve in place but it can be done.

[Deltarider]

It's virtually impossible to remove a wheel bearing and reuse it. So, unless they proof worn (simple), leave them alone. It is not my favourite job to remove a wheel bearing and that's an understatement.

[madmtnmotors]

It's virtually impossible to remove a wheel bearing and reuse it. So, unless they proof worn (simple), leave them alone. It is not my favourite job to remove a wheel bearing and that's an understatement.

Agreed. If it ain't broke....

[crashmaster]

If they don't need maintenance, as Delta rider says, might be smarter to just leave them in place. Guess I'll see how it all spins. I figured I'd have to take them out to grease them.

[bryanj]

All the "special" tools for removing bearings lock onto the inner race then some force is used to move the outer race, this WILL damage the races in someway so new bearings are needed, i am talking ball bearings here as rollers and tapers have seperate outer races

[BenelliSEI]

Curious what’s the mileage on those bearings. I’ve often removed a dust shield, cleaned and repacked the originals. My 1971 cb750K1 has 27.5K miles. When I rebuilt the wheels I had to change a rusty rim. Was I  pulled an old tire off, the rim was so rusted internally that it just collapsed when using tire irons. I replaced spokes and rim, but the bearings were perfect!

[MauiK3]

Don't use anything very abrasive on the rust, the chrome will scratch. The chrome on these bikes can look good but it isn't really the ultra hard surface some folks think it is. It's easy to scratch up.

[Stev-o]

...do you automatically change them if they are elderly?

No.  Check 'em and if nice and smooth, leave 'em. 

Why replace good bearings with [most likely] the cheap china bearings that are on the market that wont last as long?

[crashmaster]

Bike shows 16,000 miles on speedo

[Kelly E]

I'll check them out. Thanks!

Wish I had a 55 gallon drum of Evaporust for the rims 

I use a plastic rectangular flower pot filled with EvapoRust and rotate the rim every day.

[PeWe]

Rotate bearing with a finger. If it feels like sand inside, replace.

Heat the hub with a heat gun helps when removing the bearings and put new in.

[86FJNJ]

personally I'm not a fan of going down the road at 50mph on 50 year old wheel bearings. Aside from much of the grease being gone or beyond helpful you won't really know what crud has accumulated in them over the years or what little chips or cracks may exist in the bearings. I feel much better replacing them with All Balls bearings, they are not much money. I think I paid about $100 to replace the bearings on my CB750. Don't cheap out on bikes, pretty much everything can be tied back to a safety issue.

This bearing puller set works great I've used it a few times. Don't forget to reinstall the spacer between the bearings when you put in the second bearing. Stick the new bearings in the freezer overnight to shrink them just enough. Apply some WD40 to the wheel hub and heat it with a heat gun until it smokes, then quickly apply some grease to the frozen bearing and push it in place, you can save the old bearings you removed to hammer the new bearing in until they're fully seated.

https://www.amazon.com/dp/B004MAPN42?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_6

[crashmaster]

Not cheaping out. But it makes no sense to replace a part that is probably a higher quality than what is available today. Just because it's old.

[HondaMan]

I usually "ruin" (my personal term) at least one bearing when I take them out, because of the pressure (even on my press) against the inner bushing needed to push out the first one. I have several of "the other side" of those bearings that were not beat up when I had the spindle(s) out and removed the other side with a long, thin punch on the outer race. This isn't possible with all of these wheels, but with some of them it does work.

What most often makes me change them is the old, dried grease that Honda installed 50 years ago: if the bike is not frequently ridden this stuff turns to a waxy state and stands proud of the balls, so no lubrication happens - even if the bearing gets pretty warm. This causes the wear I sometimes see, which lets the wheel 'wiggle' at the outer rim. This 'wiggle' can be felt as looseness if the wear is great.

But, speaking in performance terms: you can buy extra-tight bearings (as discussed in my books) for these wheels, which are sometimes (in the USA) called "Class C" (or "reduced clearance") bearings. They cost extra, but have only 20% of the normal clearance between the balls and races. This difference can be felt in the curvy Rockies when I ride up there, and especially when riding heavy (touring 2-up with gear) as more precise steering and a more 'friendly' feeling overall in the chassis when less heavily loaded. Many years ago my 750 would 'shake its head' when coasting down steep slopes riding 1-up with only a light grip on the throttle (as did many of these bikes) because of the offset of the front wheel that was done by Honda in the later K0 chasses with the "new" front hub (it fits 2 disc brakes if you want to): the wheels were then laced up approximately 3mm away from the original disc, for whatever reason Honda wished. (This shows up in the spoke nipple threads as 1-2 thread difference, side-to-side). In the post-K0 bikes, this causes side-loading to the [front] wheel bearings when toured (like mine) for many, many tens of thousands of miles, making them wear unevenly. Then the wheel can be [measurably] wobbled (by pressing sideways on the rim), and when this reaches 1mm of looseness, I replace the bearings regardless. The handling always improves: the last 750 I just did simply stopped 'shaking its head' during a steep decel test from 80 MPH (throttle and downshift, no front brake applied) when I installed new, low-clearance bearings. The owner immediately noticed it on his first ride after he got the bike back, too.

And nowadays I lace the wheels back up on-center with the rear wheel when doing a front one. I'm still not sure what the definitive reason(s) were for Honda offsetting the front wheel of the 750 (I've heard several reasons for it), but they did it up to the 750K6.

[HondaMan]

Not cheaping out. But it makes no sense to replace a part that is probably a higher quality than what is available today. Just because it's old.

These bearings are generic: you can buy the best-of-all versions from SKF, but you'll pay for them - and they WILL be superior bearings. That's all I use.

[crashmaster]

Thanks. My point was not to swap out a part that's viable as it is.

[crashmaster]

I'll check them out. Thanks!

Wish I had a 55 gallon drum of Evaporust for the rims 

I use a plastic rectangular flower pot filled with EvapoRust and rotate the rim every day.

That's where I was headed. Thanks