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Makes And Models => Zero Motorcycles Forum | 2013+ => Topic started by: Doug S on March 20, 2016, 06:55:29 AM

Title: Ceramic bearings
Post by: Doug S on March 20, 2016, 06:55:29 AM
So I just got my bike (2014 SR with 24,000 on the clock) back from the shop. The rear wheel bearings failed a week ago Thursday, and I decided to replace them with an all-ceramic bearing. I was fortunate that I decided to do the fronts at the same time, so I ordered four bearings. Turns out there are three in the rear --two on the belt side! So I'll have to order one more before I can have the front done.

I thought I'd start a thread and if I have an early failure, let people know. I'm a little worried because, though the ceramic is harder than the steel, it's less ductile, and the weight rating is actually lower. I think failure at 24,000 miles is a wear issue, not a breakage issue, so I'm hopeful the ceramic bearing will hold up better....but I'll let you know what happens.
Title: Re: Ceramic bearings
Post by: Burton on March 20, 2016, 08:59:18 AM
I am still apprehensive about ceramics. I think in a racing situation it is required if you want to be competitive assuming you are on the same skill level with the field.

But having the bearings in my motor fail around 10k miles points out a serious flaw in their design for long term use ... at least in a motor with exposed internals and with 10 kN higher tension above stock ;)

So while the bearings were subject to near constant axial forces they didn't experience sudden jolts a wheel would experience. That said ... if they were such a bad idea for wheels then they wouldn't be able to sell them nearly as much as most motorcyclist are cheap bastards who flinch when they have to replace a 0.10$ part :D

Are your bearings fully ceramic, hybrid, or other?
What brand did you get?

I installed new wheel bearings on my rear wheel when I replaced the tire at around 13k just for the hell of it. If I recall correctly they are sealed steel bearings. I have two more bearings sitting around for whenever I replace my first front tire which I suspect will last 21 k miles or so.
Title: Re: Ceramic bearings
Post by: evtricity on March 20, 2016, 10:44:41 AM
Doug, what are the specifications of the stock bearings and suitable replacements.

Thanks
Title: Re: Ceramic bearings
Post by: Doug S on March 20, 2016, 08:11:37 PM
I went with a full ceramic, sealed bearing:

http://www.bocabearings.com/bearing-inventory/Radial-Full-Ceramic-Bearings/16454/20x37x9-6904BBTPC3ZS5SRL (http://www.bocabearings.com/bearing-inventory/Radial-Full-Ceramic-Bearings/16454/20x37x9-6904BBTPC3ZS5SRL)

They were a bit cheaper when I bought them, apparently their "special price" isn't quite as special now.

On the ride home yesterday (20 miles, all freeway), the rear of the bike felt a bit tighter than it was, both in the "under better control" sense and in the "won't coast as far" sense. It also felt extremely smooth and vibration-free. I presume all of these changes are just comparing worn bearings to fresh ones, but maybe the ceramic ones are better. The ones I picked do have an ABEC 5 rating with grade 5 balls and a C3 fit.
Title: Re: Ceramic bearings
Post by: evtricity on March 21, 2016, 06:20:26 AM
Thanks Doug
Title: Re: Ceramic bearings
Post by: laramie LC4 on March 22, 2016, 07:10:39 AM
you guys also need to understand that manufacturers will only spend so much on bearings. at some point they start loosing money or people start to complaining about the prices. any time you remove an OEM bearing, the first thing you should do is take the bearings and any seals down to a real bearing shop (MY FAV (https://www.motionindustries.com/productCatalogSearch.jsp)) and speak to someone who knows what they are talking about. they will get you better bearings and seals, and it's usually much cheaper than going back to the original manufacturer of the bike. they will also be able to tell you if ceramic, steel, roller, ball, .... is going to work best.

Title: Re: Ceramic bearings
Post by: Killroy on March 22, 2016, 08:21:41 AM
How many miles are you getting out of a bearing?  Should last over 30K miles.
Title: Re: Ceramic bearings
Post by: Richard230 on March 22, 2016, 08:22:02 PM
How many miles are you getting out of a bearing?  Should last over 30K miles.

My daughter's 1986 VFR 700FII and her 1981 BMW R65LS both have around 100K miles on their clocks and they still have their original wheel bearings, which have never even been re-greased (being of the sealed-type) or serviced in any way. So good quality wheel bearings, properly greased at the factory, can last a very long time under normal (no wheelies or off-road) use.  :)
Title: Re: Ceramic bearings
Post by: Killroy on March 23, 2016, 03:58:17 AM
Agreed.  I have never replaced a wheel bearing on a car. 

A motorcycle noes not need to have parts last as long since most motorcycles don't drive that much, but it would be sad to replace a wheel bearing before a car replaces a touring tire.

Sure there will be premature failure, but wheel bearings should last >50,000 miles. 
Title: Re: Ceramic bearings
Post by: BrianTRice@gmail.com on March 23, 2016, 04:02:00 AM
Just chiming in agreement with the above about bearing expectations.

One reason for upgrading or considering a 15-16 Zero model over older models is the more robust bearing size/spec for touring. My V-Strom bearings lasted 40k miles (with 10% offroad use and 10% 500 mile touring days) compared to ~13k miles for the 13 DS. Having a long interval just makes it easier to take off on long trips.
Title: Re: Ceramic bearings
Post by: evtricity on March 23, 2016, 04:08:48 AM
Saw this in another thread and I had to call it out here.

It's difficult to justify buying a new bike when replacement bearings are under $100 for front and rear wheels. I'm a great supporter of Zero but like most of us, I can't afford to replace our expensive bikes every 2 or 3 years!
Title: Re: Ceramic bearings
Post by: BrianTRice@gmail.com on March 23, 2016, 05:03:25 AM
Saw this in another thread and I had to call it out here.

It's difficult to justify buying a new bike when replacement bearings are under $100 for front and rear wheels. I'm a great supporter of Zero but like most of us, I can't afford to replace our expensive bikes every 2 or 3 years!

Whoa, hey, I listed it as a reason; that's all. I have different goals and priorities than normal, so I acted differently. If it makes you feel any better, I have no kids, don't own a car, use Craigslist/EBay to find secondhand deals, and scrounge for cheaper real estate that fits my needs and saves money. So, upgrading my bike is something I design my budget around.

Also, it took me months to justify the expense, when I had already stocked up on secondhand spare consumable parts [bearings, brake pads, etc] for the 13 DS which I will pass on to its eventual buyer.

On to chapter N+1 of "saying things on the internet is fraught with misunderstanding"...
Title: Re: Ceramic bearings
Post by: RickXB on March 23, 2016, 05:39:26 AM
Did it increase the range vs stock bearing?
Title: Re: Ceramic bearings
Post by: evtricity on March 23, 2016, 05:40:20 AM
Hi Brian, didn't mean to have a go at you personally. Apologies if it came across that way.  I acknowledge you stated it was "one reason" to upgrade but given the cost to change one set of bearings it's not compelling for me. As mentioned, my comment also referred to another post on another "bearing" topic on this forum. In hindsight, I should have made my post there.

It said - "If you have a 2012, 2013 or 2014 and are having issues with little things, instead of trying to replace all these little things one by one, it might cost less in the long run to upgrade to a 2015 or new 2016 bike." Since a replacement of OEM bearings is cheap and you only do it once (after that you should have the same quality bearing as any other motorcycle), I believe it's a minor reason at best.

I can't speak about the 2012 or 2013 bikes (as I have a 2014 SR) but I doubt there are enough "little issues" in the 2014 bikes to justify spending anywhere near USD10,000+ or AUD20,000+ on a new bike!

There are "big issues" in the 2014 with suspension, motor etc but even then it's still difficult to justify upgrading every 2-3 years especially when the resale value on Zeros (like other motorcycles) is pretty low (at least in Australia where a new AUD25,000 SR sells for AUD15,000 after 1 year and AUD10,000 after 2 years).

Apologies for the hijack, back to the bearing discussion ...
Title: Re: Ceramic bearings
Post by: Doug S on March 23, 2016, 06:22:29 AM
Did it increase the range vs stock bearing?

If that's directed at me, it doesn't seem so, or at least not enough to be immediately obvious. I've only commuted on it twice now, and it's doing exactly what it's always done.

I've seen a thousand of those "wheel spins forever on ceramic bearing" videos, and I suspect they're all comparing a greased, sealed metal bearing with an open, ungreased ceramic bearing. Both the grease and the seal add some friction, but it's not worth talking about, and you'd be crazy to ever run a bearing (even a ceramic bearing) ungreased. I don't think the "it spins forever" test is very representative of the bearing's performance under real-world load.
Title: Re: Ceramic bearings
Post by: Fivespeed302 on March 25, 2016, 04:29:21 PM
Did it increase the range vs stock bearing?

If that's directed at me, it doesn't seem so, or at least not enough to be immediately obvious. I've only commuted on it twice now, and it's doing exactly what it's always done.

I've seen a thousand of those "wheel spins forever on ceramic bearing" videos, and I suspect they're all comparing a greased, sealed metal bearing with an open, ungreased ceramic bearing. Both the grease and the seal add some friction, but it's not worth talking about, and you'd be crazy to ever run a bearing (even a ceramic bearing) ungreased. I don't think the "it spins forever" test is very representative of the bearing's performance under real-world load.

Like this guy?  (I love AvE's videos, BTW)

https://youtu.be/uD7Lzv5fWhs
Title: Re: Ceramic bearings
Post by: Lipo423 on March 26, 2016, 02:00:38 PM
Mmm...I would not suggest you to get ceramic bearings, the price difference will not pay off

I have no experience having them installed on motorbikes, but I have a wide nice experience in bicycles (I clarify the words to avoid confusion). They are suitable for reducing drag and improve life in "soft applications" I guess you know what I mean...as soon as you get the rough word in the middle of the conversation you will destroy them same way -or faster- than regular steel bearings (this is my experience -I own 7 bicycles-)

For people like us (99% do not race with the bikes, or can afford to replace them on regular bases), get SKF new bearings with the suitable required type/model (a bearing shop will tell you what to go for), and you should be ok.

I have not checked Zero wheel bearings but I bet you one beer they are not top notch  ;)
Title: Re: Ceramic bearings
Post by: MrDude_1 on March 31, 2016, 12:07:45 AM
Mmm...I would not suggest you to get ceramic bearings, the price difference will not pay off

I have no experience having them installed on motorbikes, but I have a wide nice experience in bicycles (I clarify the words to avoid confusion). They are suitable for reducing drag and improve life in "soft applications" I guess you know what I mean...as soon as you get the rough word in the middle of the conversation you will destroy them same way -or faster- than regular steel bearings (this is my experience -I own 7 bicycles-)

For people like us (99% do not race with the bikes, or can afford to replace them on regular bases), get SKF new bearings with the suitable required type/model (a bearing shop will tell you what to go for), and you should be ok.

I have not checked Zero wheel bearings but I bet you one beer they are not top notch  ;)

just for clarity.... the ceramic bearings on bicycles are undersized for minimal friction and to make them "as efficient as possible" at the expense of being weak to the point that a couple curb jumps would trash them.... but they're intended for bikes where a couple curb jumps would demand a new rim, tire and possibly new frame.

In the case of motorcycles, they're still strong enough.... however as soon as trash gets in there, they will destroy themselves.. so axle/bearing seals are critical, and they're no good at off-road applications, double so if watercrossing is expected
.
Title: Re: Ceramic bearings
Post by: Doug S on March 31, 2016, 12:57:46 AM
When I found out the bearings had failed on my bike, I needed to decide what I wanted to do, and fast, so the bike wouldn't sit in the shop forever. I did a lot of reading on ceramic bearings in one evening, and found out there's very little scientific information and a bazillion opinions on ceramic bearings. We do know they're harder than steel bearings; that's quantifiable. It's also clear they're a lot more expensive. It also seems pretty undeniable that they're more brittle than steel, but I haven't seen any hard numbers showing that to be true, and I also don't pretend to know what's "tough enough" for a bearing to survive impacts without shattering or dimpling the races.

I've heard that "they'll wear longer", which seems plausible; they are harder, so it seems like wear particles might break off less frequently. But I've also heard they "don't last as long", which might be due to premature shattering, dimpling, or it may just be because people run them dry, without grease -- they're usually used by high-performance types that want them for their lighter weight and perceived lower friction.

So I decided I'd try them. If they do last longer, I may well never have to replace them again (I got 24,000 miles out of the original set). If it doesn't work, I'll just go back to steel, and I'll just have to get them replaced once in a while.

In a way this isn't a valid experiment, though, since in addition to going with ceramic, I'm pretty sure I upgraded them spec-wise too. The ones I chose are ABEC 5, C3 fit, and have Grade 5 balls, which is a pretty high-precision bearing, so it's probably not fair to compare to the originals (which I assume are mid-grade at best). Even the upgraded bearings are still cheaper than having another set put in down the road, however.
Title: Re: Ceramic bearings
Post by: Lipo423 on July 01, 2016, 02:41:54 PM
Doug,

What is your experience so far with the ceramic bearings?
I'm just curious...
Title: Re: Ceramic bearings
Post by: Doug S on July 01, 2016, 07:00:42 PM
Doug,

What is your experience so far with the ceramic bearings?
I'm just curious...

So far, so good. I didn't record the mileage when I replaced them, but based on the date it was probably 3,000 miles ago. The rear end is still smooth as silk. And I'm a big guy (300 pounds), so I'm a pretty tough load for bearings.
Title: Re: Ceramic bearings
Post by: Killroy on July 01, 2016, 07:36:33 PM
There are probably better gains switching the belt for a chain.
Title: Re: Ceramic bearings
Post by: Doug S on July 01, 2016, 08:13:48 PM
I'm not concerned about efficiency gains. I'm concerned with the life of the bearings.
Title: Re: Ceramic bearings
Post by: DynoMutt on July 02, 2016, 12:58:36 AM
How would they survive crappy roads with lots of pot holes?

I wouldn't want one shattering under me because of a pot hole impact.
Title: Re: Ceramic bearings
Post by: Doug S on July 02, 2016, 01:01:22 AM
I've banged across plenty of potholes, and like I said, I'm a good bearing load tester. No problems so far.
Title: Re: Ceramic bearings
Post by: Doug S on March 09, 2017, 03:05:05 AM
Update: I'm over 30,000 on the clock now, so at least 6,000 on the new bearings. Not a single problem so far.
Title: Re: Ceramic bearings
Post by: Fivespeed302 on April 21, 2017, 03:58:25 PM
Update: I'm over 30,000 on the clock now, so at least 6,000 on the new bearings. Not a single problem so far.

That's great to hear.  I'm about to hit 14,000 on my bike (original bearings).  I'd be closer to 16-17,000 if I hadn't had my initial 3 visits to the dealer for the well known on board charger failures and then the time it was in the shop after some old lady ran it over in a parking lot.  I got it almost exactly two years ago.
Title: Re: Ceramic bearings
Post by: BrianTRice@gmail.com on June 07, 2017, 01:37:31 AM
I filled in a section of the manual to accommodate this success report:
http://zeromanual.com/index.php/Unofficial_Service_Manual#Rear_Bearings (http://zeromanual.com/index.php/Unofficial_Service_Manual#Rear_Bearings)
Title: Re: Ceramic bearings
Post by: Doug S on June 29, 2018, 09:04:20 PM
Update: The experiment is over. I was riding home from work a couple of days ago and a heavy-duty giant plastic bag wrapped itself around the right side of my rear axle. By the time I could get off the freeway and even attempt to clear it, it was too late. The axle was moving around in the frame and it was clear the bearing(s) had been destroyed.

At this point, I'm considering taking Terry's advice and having the shop install a 2015 (or later) wheel on the bike. The larger bearings really appeal to me at the moment.

I've got almost 41,000 miles on the bike now, so the new (ceramic) bearings lasted almost as long as the originals, and weren't giving any hint of a problem until they were murdered by the debris I picked up. Also, for whatever reason, the price of the ceramic bearings I bought has tripled since I bought them, and if I'm going to have to spend $300 on just new bearings, I'm going to at least check out the price of a new wheel.
Title: Re: Ceramic bearings
Post by: Perseverius on July 03, 2018, 07:39:12 PM
But having the bearings in my motor fail around 10k miles points out a serious flaw in their design for long term use ... at least in a motor with exposed internals and with 10 kN higher tension above stock ;)

So while the bearings were subject to near constant axial forces they didn't experience sudden jolts a wheel would experience. That said ... if they were such a bad idea for wheels then they wouldn't be able to sell them nearly as much as most motorcyclist are cheap bastards who flinch when they have to replace a 0.10$ part :D


I'm in the sad position where my motor bearings seem to have worn out. There are 2 reasons for me to suspect this. Firstly there is a slight noise coming from the motor and secondly I'm able to slightly move the pulley up and down by hand. Plus the motor doesn't feel as punchy as it used to. My local Zero dealer have proven themselves to be a bunch of scamsters, so I'm left to my own devices. Is there anywhere that I can find more motor info? Is it even possible to replace the bearings yourself, or do I need to find electric motor specialists?
This is all I have so far: http://motenergy.com/mepmbrmo.html
Title: Re: Ceramic bearings
Post by: rayivers on July 03, 2018, 08:09:07 PM
Quote
The axle was moving around in the frame and it was clear the bearing(s) had been destroyed.

Wow - so the bag got past the outer wheel seal and RH bearing seal in a matter of seconds?  Or was the bearing unsealed?

FWIW, my Ortech stainless/ceramic wheel bearings loosened up after 780 dirt miles and I replaced them with generic eBay stainless ones, which are holding up fine so far.  The bigger Ortechs in the swingarm pivot seem to be doing well too. 

The later big-bearing wheels are surely a good idea if you plan to keep the bike.
Title: Re: Ceramic bearings
Post by: quixotic on July 04, 2018, 12:17:57 AM
Agreed.  I have never replaced a wheel bearing on a car. 

A motorcycle noes not need to have parts last as long since most motorcycles don't drive that much, but it would be sad to replace a wheel bearing before a car replaces a touring tire.

Sure there will be premature failure, but wheel bearings should last >50,000 miles.

I recall reading somewhere that the old BMWs had wheel bearings, which, if re-greased at the specified intervals, would last well over a million miles. 

Edit: guess I made a mistake.  Should be billion, not million.  https://w6rec.com/bmw-motorcycle-wheel-bearings-1956-through-84-repair-preload-and-spun-hubs/

Title: Re: Ceramic bearings
Post by: Richard230 on July 04, 2018, 03:52:37 AM
Agreed.  I have never replaced a wheel bearing on a car. 

A motorcycle noes not need to have parts last as long since most motorcycles don't drive that much, but it would be sad to replace a wheel bearing before a car replaces a touring tire.

Sure there will be premature failure, but wheel bearings should last >50,000 miles.

I recall reading somewhere that the old BMWs had wheel bearings, which, if re-greased at the specified intervals, would last well over a million miles. 

Edit: guess I made a mistake.  Should be billion, not million.  https://w6rec.com/bmw-motorcycle-wheel-bearings-1956-through-84-repair-preload-and-spun-hubs/

My daughter has a 1981 BMW R65LS with over 100,000 miles on the clock.  Her wheel bearings have never been greased or serviced and they are still working just fine.  I might add that she also has the original BMW factory tool kit under her seat and the tools, except for the fabric tool kit roll which is quite worn, still look like new.  Not a drop of rust.  :)  The quality of BMW components were of a very high quality in those days.
Title: Re: Ceramic bearings
Post by: Doug S on July 05, 2018, 07:21:29 AM
Wow - so the bag got past the outer wheel seal and RH bearing seal in a matter of seconds?  Or was the bearing unsealed?

It was a sealed ceramic bearing (see earlier in the thread), but I don't think the bag got inside the bearing. It just wrapped itself so thoroughly around the wheel/frame junction that it overloaded the bearings to the point of failure. The bike was obviously laboring, twitching heavily, and I was fortunate to be able to even get it off the freeway without dropping the bike. This was NOT a dry cleaning garment bag. It was very thick, heavy plastic, a large piece. Something like a factory might use to ship an engine block.

Quote
The later big-bearing wheels are surely a good idea if you plan to keep the bike.

Agreed. It's very clear those bearings are under-engineered. I was hoping a "better" bearing would be an acceptable cheaper fix, and it may have been if this incident hadn't happened. But it clearly didn't have sufficient margin for error to handle this unexpected load.
Title: Re: Ceramic bearings
Post by: rayivers on July 05, 2018, 07:59:49 AM
Wow - you're so lucky the wheel didn't immediately lock up solid, it might've been real bad.

Yeah, the small bearings just don't have any safety margin at all, especially for dirt use or if something unexpected happens like your event.  I'll probably run mine till they start loosening up, then swap 'em out.
Title: Re: Ceramic bearings
Post by: togo on February 12, 2019, 05:58:48 AM
> At this point, I'm considering taking Terry's advice and having the shop install a 2015 (or later) wheel on the bike. The larger bearings really appeal to me at the moment.

I'm going through this process right now.  I bought the 2015+ wheel, but it looks like it needs different spacers than my 2014 SR has.