Bicycle bearing grease lab test help

Originally Posted By: Kestas
I think you should exclude the kerb crash test. This test is used to test the raceways for dent resistance. As I said, grease is not a variable in this test. You could run it without grease and have the same results. The tire is included because this is how the test was developed. The test has very specific parameters (i.e., drop height, load, angle) that I am mot intimately familiar with.

There are books in the library of educational institutions that cover bearing design and theory. Common bearing failure modes can be found on the internet.

Your water and dirt tests have merit.

I wouldn't measure wear by weighing the bearings. It's not practical and it won't yield anything useful. Wear is typically assessed by examination of the raceways. It's not really quantified.

Another test that may be useful is a raceway fretting test. This tests the effectiveness of grease during micromotion of raceways, such as the steer tube bearings. Different greases have markedly different results with this test. I believe there already is a standardized test for this in the industry.


Visual inspection definitely - for signs of wear and/or pitting, along with photos. Weighing on a precise scale will be an addition, to (double) check for wear. Since the bearings I plan on using are cartridge ones, not practical for disassembling, weighing will show any worn off material. Weighing before test (after degreasing and cleaning), then adding grease, testing and weighing afterwards.

For fretting test - yes, my plan so far doesn't include the test - and yes, it's important for steerer bearings. Maybe on another occasion. I'll see how this goes. Next week I'm going to talk to the lab guys and see what exactly we can do, how much time will be available.

As for bearing construction and wear - I've read quite a bit so far, but very little data on steel vs ceramics.
In my experience - dirt intrusion and grease depletion is what kills most bike bearings. Ceramics are practically immune to grease depletion (no rusting, no welding, need very little lube to run smooth), but after a few rides and dirt intrusion - I doubt they differ much from steel ones. Using simple dust seals to prevent dirt intrusion does increase drag. On top of that, I'm still looking for a test of how faster a bike rolls with ceramic bearings, especially after a few rides in the rain.
 
Originally Posted By: ArcticDriver

Its true that many cyclists spend $5K on bicycles and costumes today as a form of status; however, there are still a few of us who ride older bicycles...gasp...and practice a strong economy.

We are the ones not wearing spandex outfits into the local SBUX Forcing all the customers to see our 60-year-old glutes.

And I can think of a few old bike shop owners who would prefer to save overhead costs by purchasing a quality grease at half the price.

Cheers



Not sure where all this is coming from old boy? At least I stayed on topic. Let's see, 2 of the bikes I ride are a '96 and an '00, but I did upgrade from an '07 to a '16 last year as the '07 needed obsolete parts. Sorry. As for old guy's butts in spandex, since I don't frequent SBUX ever that's not a big problem for me. And having raced both road and mountain bikes in younger days and understand the need for the tights maybe I'm more tolerant of them. Maybe get your SBUX latte to go?

And it sounds like the OPs stated purpose is to find out if low cost grease is as good as expensive grease so the old bike shop owners aren't going to get their quality grease at half price. It seems plausible that cone/cup bearings will last forever in bikes if maintained so the need for special grease could be unnecessary. IF MAINTAINED is the thing right? If a quality grease will stay in the bearing and not wash out under harsh use and only need repacking once a year instead of twice a year does that offset the actual cost of the grease? As stated earlier labor far outweighs cost of grease.
 
Originally Posted By: CR94


1. Although absolute load on bicycle wheel bearings is obviously a lot less than that of a small car, EP qualities of the grease do matter, because specific loading (stress within the much smaller bearing races) is often higher. That's one reason why life of bike bearings is generally shorter.


3. Chain tension can add greatly to overall load on right rear wheel bearings, especially when climbing hills. Do the vector math, using reasonable assumptions, and you'll see. On steep hills, it can exceed load due weight of rider+bike.

4. To better simulate riding in rain, you need to subject your bearing to periods of continuous spray, not just dump mixture over them intermittently. The life of bike bearings tends to be highly dependent on the water resistance qualities of the grease.



That's one reason why I'm very particular about grease for my bikes - a lot of bike shops use Park PolyLube 1000, a polyurea-based grease for pure convenience as they can get it from QBP and it's sold as a "bike-specific" grease. I've seen Park PolyLube break down during use - and typically polyurea greases aren't compatible with any other greases. Shimano uses calcium-based grease which naturally has high water wash resistance.

As for bearing load, Shimano did switch over to the freehub system in the 1980s - rear axles were getting bent as soon as bikes had more gears in the back. There's 3 sets of bearings in their system - all cup and cone and one of them is in the freehub body. SRAM is pushing their XD driver system on mountain bikes. But outside of Shimano, very few hubs use angular contact bearings which will spread load evenly instead of concentrating it at one spot, could that be why some bearings fail quicker than others?
 
Originally Posted By: nthach
... very few hubs use angular contact bearings which will spread load evenly instead of concentrating it at one spot, could that be why some bearings fail quicker than others?

I don't understand this question.
 
Originally Posted By: Kestas
Originally Posted By: nthach
... very few hubs use angular contact bearings which will spread load evenly instead of concentrating it at one spot, could that be why some bearings fail quicker than others?

I don't understand this question.

What I meant to say in a bicycle application which sees both axial and radial forces like wheels, is a angular contact bearing better than a conventional deep groove bearing due to that load seems to be spread out more evenly with an angular bearing?
 
Originally Posted By: nthach
Originally Posted By: Kestas
Originally Posted By: nthach
... very few hubs use angular contact bearings which will spread load evenly instead of concentrating it at one spot, could that be why some bearings fail quicker than others?

I don't understand this question.

What I meant to say in a bicycle application which sees both axial and radial forces like wheels, is a angular contact bearing better than a conventional deep groove bearing due to that load seems to be spread out more evenly with an angular bearing?


Angular contact bearings are better for the application - they do handle lateral loads better.
 
Originally Posted By: CycleGremlin
... Angular contact bearings are better for the application - they do handle lateral loads better.
True, but lateral or axial loading of bike bearings is generally much smaller than the radial loads, except in headsets---and crashes.
 
Originally Posted By: CR94
Originally Posted By: CycleGremlin
... Angular contact bearings are better for the application - they do handle lateral loads better.
True, but lateral or axial loading of bike bearings is generally much smaller than the radial loads, except in headsets---and crashes.


Which is why radial bearings (most modern cartridge ones are made as such) don't create much problems after a short time. Still, when riding standing (pedalling up hill, or sprinting), there are lateral loads as well. Also, when cornering without leaning the body with the bike (off road style, with the body more upright), there are lateral loads present.

Living car free for the past 10+ years (using motorcycle for sports, but not for transport), I've been riding all year long (summer heat, as well as snow and melted, salty snow). Doing about 5000+ km per year. Servicing cup and cone hubs every spring and autumn, they last until a bike gets stolen. No measurable wear on the bearings. No serviceable radial bearings for comparison unfortunately. One bike was serviced once a year and no wear for 3 years (then it got stolen), but that's not a very long time. I do twice a year service just for a piece of mind (mostly looking for dirt intrusion, or grease washout, but once I open the hubs - see no point in not cleaning and re-lubing).
 
Hello and welcome.
I have few questions
1. I did not get what is the purpose of this test. What do you want to proof with it?
2. What is the accuracy of weight measurements? - e.g. wear of 10um at outer shell weights 0.0078mg - milligrams
 
Pre 1970's Raleigh 3 speed English bicycles "The all steel bicycle" were built to last 100 years. I have been picking these out of the trash or buying very cheap for years and refurbishing them. They usually have sat in a garage or basement for 20-30 years. It takes very little to get them rolling as new again without replacing any parts other than tires & brake pads generally. I just use a cheap light grease wheelhub, BB,& headset. Sturmey Archer Internal gear hubs are designed to use a very light oil such as Dextron or even lighter. these IGH hubs are design to run on the oil alone but to grease bearing sets lasts for years and the oil mess is then controlled you need very little light oil in the hub.
When I disassemble the bearing the grease is usually petrified on parts. These Raleigh built bikes are aged 1958-59-60-61-63-64-68-69-70-71 and a 1985 made in Asia. Late 70's Raleighs are Asian made. They all work perfect & I ride 2 of them and they never break and need very little care than a squirt of dextron on the chain once in a while. My daily rider is outside 24/7 I ride most every day It is minus 1 dergree F this morning.
 
Last edited:
Originally Posted By: johnnyspaghetti
Pre 1970's Raleigh 3 speed English bicycles "The all steel bicycle" were built to last 100 years. I have been picking these out of the trash or buying very cheap for years and refurbishing them. They usually have sat in a garage or basement for 20-30 years. It takes very little to get them rolling as new again without replacing any parts other than tires & brake pads generally. I just use a cheap light grease wheelhub, BB,& headset. Sturmey Archer Internal gear hubs are designed to use a very light oil such as Dextron or even lighter. these IGH hubs are design to run on the oil alone but to grease bearing sets lasts for years and the oil mess is then controlled you need very little light oil in the hub.
When I disassemble the bearing the grease is usually petrified on parts. These Raleigh built bikes are aged 1958-59-60-61-63-64-68-69-70-71 and a 1985 made in Asia. Late 70's Raleighs are Asian made. They all work perfect & I ride 2 of them and they never break and need very little care than a squirt of dextron on the chain once in a while. My daily rider is outside 24/7 I ride most every day It is minus 1 dergree F this morning.
Welcome Aboard!

Nice post
 
Since you resurrected this old thread...

As a bike mechanic (formerly professional) over the past 30-40 years, I've found that most cheap greases do a poor job in bicycle bearings. They tend to migrate out of the bearings, fail to prevent corrosion, spalling and other forms of metal wear. Packing the bearings 100% full with a quality grease makes a big difference. When I do this, I can open the bearings several years / thousands of miles later and the grease is all still there and the bearings are still in like-new condition. Even with cartridge bearings, I prefer to pop off the plastic seals, clean out the old grease, repack them full of quality grease, pop the plastic seals back on and put them back into service - rather than replacing them.

By "quality" I mean a grease that resists water, resists oil separation, and has tackifier agents to help it stay in the bearings where it belongs. I use Schaeffer's 221 #2, though no doubt there are other good options. As for "bicycle" greases like Phil Wood and others, they're better than the crappy OEM grease that is often used, but that's not saying much, and I find that Schaeffer's holds up better.
 
Since you resurrected this old thread...

As a bike mechanic (formerly professional) over the past 30-40 years, I've found that most cheap greases do a poor job in bicycle bearings. They tend to migrate out of the bearings, fail to prevent corrosion, spalling and other forms of metal wear. Packing the bearings 100% full with a quality grease makes a big difference. When I do this, I can open the bearings several years / thousands of miles later and the grease is all still there and the bearings are still in like-new condition. Even with cartridge bearings, I prefer to pop off the plastic seals, clean out the old grease, repack them full of quality grease, pop the plastic seals back on and put them back into service - rather than replacing them.

By "quality" I mean a grease that resists water, resists oil separation, and has tackifier agents to help it stay in the bearings where it belongs. I use Schaeffer's 221 #2, though no doubt there are other good options. As for "bicycle" greases like Phil Wood and others, they're better than the crappy OEM grease that is often used, but that's not saying much, and I find that Schaeffer's holds up better.

Phil grease was rather thin though. I remember going to a bike shop where they recommended against using it in Campy hubs since they didn't have a plastic cap and supposedly grease would migrate out the cones quickly. They said it was OK in Shimano or other hubs. Also - they said something about Campy's warranty only being valid if they were repacked with Campy bearings and grease (which I believe was a white lithium type), but I wasn't paying those prices. They just sold me industrial bearings and I used a fairly good white lithium grease. I hear that they discontinued selling that grease.

But one of the weirdest things I read about was Eddy Merckx's attempt on the hour record in Mexico City. They did everything to reduce weight even if they sounded extreme, including using the thinnest cranks and removing the dust caps from the hubs to reduce that little bit of weight. I'm wondering how quickly the grease got gritty and how much escaped.
 
... Also - they said something about Campy's warranty only being valid if they were repacked with Campy bearings and grease (which I believe was a white lithium type), but I wasn't paying those prices. ...
That sounds consistent with my experience. The OEM grease for the Campy super record on my 1980s race bike was a medium viscosity white lithium type. It was better than the crappy OEM grease used in most other bearings including Shimano. When servicing that Campy I used a slightly higher viscosity white lithium grease. It wasn't Campy grease, but it worked at least as well.

Removing dust caps from the wheel hubs is crazy. You're saving a few grams, no real benefit only drawbacks. I can't imagine any professional mechanic going along with that. However, when you're Eddie Merckx you get what you ask for even if it's crazy.
 
That sounds consistent with my experience. The OEM grease for the Campy super record on my 1980s race bike was a medium viscosity white lithium type. It was better than the crappy OEM grease used in most other bearings including Shimano. When servicing that Campy I used a slightly higher viscosity white lithium grease. It wasn't Campy grease, but it worked at least as well.

Removing dust caps from the wheel hubs is crazy. You're saving a few grams, no real benefit only drawbacks. I can't imagine any professional mechanic going along with that. However, when you're Eddie Merckx you get what you ask for even if it's crazy.

It was just the hour record and the bike would only be used once. Not sure if it would have been rebuilt for another attempt, or if they would have just replaced the whole wheel. The record attempt was often attempted at altitude to reduce drag effects, although I'm not sure how much the removal of dust caps would increase drag.

Here's the bike.

img_2330.jpg


I couldn't find a closeup of the front hub, but the rear clearly is missing the dust cap.

img_2332.jpg


No dust cap on the crank either.

img_2333.jpg
 
The crank dust cap is no big deal, it doesn't really do anything. But removing the wheel bearing dust cap exposes the bearings. However, now that I see the clipped photos above it looks like it was a track event, which makes more sense. Much less likely to contaminate the bearings.
 
The crank dust cap is no big deal, it doesn't really do anything. But removing the wheel bearing dust cap exposes the bearings. However, now that I see the clipped photos above it looks like it was a track event, which makes more sense. Much less likely to contaminate the bearings.

The hour attempt is by definition at a velodrome, although quite a few of the attempts were at lower altitudes. The one in Mexico City (same venue used for the 1968 Olympics) is at about 6500 feet elevation so it has some interesting tradeoffs where the riders have to acclimate. I heard when Greg Lemond had a planned attempt in Mexico City, he trained at sea level using some rig to breathe in air that would simulate the altitude.

IMG_4478.jpg


But absolutely the bearings would be likely trashed without the dust caps. I wasn't quite sure whether or not it might be counterproductive since the grease will likely be ejected and stuff getting in the bearings might start increasing friction.
 
... But absolutely the bearings would be likely trashed without the dust caps. I wasn't quite sure whether or not it might be counterproductive since the grease will likely be ejected and stuff getting in the bearings might start increasing friction.
Agreed. Sometimes people do crazy stuff with bikes that isn't always supported by physics or engineering. In that way it can be like audiophiles with their green pens, cable lifts, and fancy power cords.
 
Agreed. Sometimes people do crazy stuff with bikes that isn't always supported by physics or engineering. In that way it can be like audiophiles with their green pens, cable lifts, and fancy power cords.

What’s a cable lift? When I was into that sort of thing I remember going to one shop where the manager was extolling the virtues of welded cables as being sonically superior to soldered or crimped cables, and tried to get me to look up some white paper by some guy making those claims. My engineering professors would have laughed that off. I do remember going to one place where one of the entire staff said that people who thought that cables made a significant difference beyond just adequate noise shielding and thick enough speaker cables were delusional.
 
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