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Bearings are bearings aren't they?

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I say there's no difference in crank or tranny bearings from a bearing supply house and the expen$ive one$ from the dealer parts counter. The number is right there on the side of the bearing.   There's a significant price difference though

 

I say they're all the same except the packaging.  Using the less expensive ones has never failed me.  Anybody got a different opinion? 

Edited by Jimmy Pascol

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Bearings from an industrial supply house are very often a better quality product than the bike brand. Less expensive normally since there is not a kool aid markup factor involved. You're doing it right. American made bearings are by far the best in the world if you can find them.

Edited by YHGEORGE
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usually skf or fafnir are good bearings. numbers just designate size,such as 6203. c2 or c3,etc. designate whether bearing has a tighter internal clearance between races and balls,not race size as to fit. Chinese bearings are cheaper,and poor quality,as a general rule. Have tried many brands attempting to save,as I work for a manufacturing company. We ended up going back to good brand American or Japanese made bearings,because of customer complaints and bearing failures.

In ball bearings, as the radial clearance increases, the axial clearance increases as well. The more room between the balls and the rings (radial clearance), the more the elements can shift in relation to each other. Generally, internal clearances are designated from C1 (the tightest) through to C5 (the loosest or largest). The 'normal' clearance is CN, a range sitting between C2 and C3. It is worth noting that if the bearing clearance is not stated in the bearing reference it can be assumed to be normal clearance. With a higher clearance there is more tolerance of thermal expansion effects on the rings and rolling elements. When noise and vibration must be restricted, lower clearances are necessary. Ultimately the specific application and operating conditions determine the appropriate internal clearance. For example, paper-drying machines that operate under hot conditions usually need C3 and C4 clearances. The severe vibration in vibrating screens normally means that C3 and C4 clearances are required. Selection of the correct radial internal clearance group is by calculation and you should refer to your bearing manufacturers handbook.

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Good post.

I would add that crank bearings, at least on 2Ts, use looser clearances because of the thermo variations inside the crankcase.  For that reason it is usually better to use OEM supplied bearings.

 

Wheel bearings operate at a fraction of their design load and speeds and the failure mod is almost always from water contamination so  using cheap sealed bearings is cost effective.

 

Our bikes use mostly standard metric bearings with a few being a custom size available only from the mfg. The bearing number and other info is etched on the side of the outer race.

I try to buy all of my bearings from industrial bearing suppliers, just check your local yellow pages or google. 

 

They often have choices based on price point and quality.

 

see http://www.smbbearings.com/Popular_Metric_Bearings.htm for more bearing data

#......... ID.. OD.. TH
6000.. 10.. 26.... 8
16100.10.. 28.... 8
6200.. 10.. 30.... 9
6300.. 10.. 35... 11
16001 12.. 28.... 7
6001.. 12.. 28.... 8
6201.. 12.. 32.. 10
16101 12.. 32.... 8
6301.. 12.. 37.. 12
6802.. 15.. 24.... 5
6902.. 15.. 28.... 7
16002 15.. 32.... 8
6002.. 15.. 32.... 9
6202.. 15.. 35.. 11
6302.. 15.. 42.. 13
6003.. 17.. 35.. 10
16003 17.. 35.... 8
6203.. 17.. 40.. 12
6003.. 17.. 35.. 10
6303.. 17.. 47.. 14
6904.. 20.. 37.... 9
6004.. 20.. 42.. 12
6204.. 20.. 47.. 14
6304.. 20.. 52.. 15
16005 25.. 47.... 8
6005.. 25.. 47.. 12
6205.. 25.. 52.. 15
6305.. 25.. 62.. 17
16006 30.. 55.... 9
6006.. 30.. 55.. 13
6206.. 30.. 62.. 16
6306.. 30.. 72.. 19
The last digit indicates the bearing ID; 1=12mm, 2=15mm, 3=17mm.  4 and above multiply by 5, e.g. 4=20mm, 5=25mm.

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I have made the mistake to take the cheap route, one damaged hub later and a visit to my motor cycle salvage yard, I now pay the price for genuine Honda parts, bearing included!

Not enough details.

 

I've been buying from bearing suppliers since the mid sixties and have not had any damaged hubs.

And I always use sealed bearings.

 

I almost always get the bearings I want on first trip while a dealer needs to order them and I get to make a second trip a week later to pick them up.

 

About a decade ago I started buying double so I'd have spares on hand, still cheaper than the local stealership.

 

Bearings are a world wide industrial commodity,  loads and speed for wheel bearing use is fraction the bearing's design rating.

Common wheel bearing failure mode is water ingestion and dirt contamination, that is why I always use sealed bearings.

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I like the posts about the different classes and different materials for a particular sized bearing. I do not know enough about bearings to make an educated guess but I do trust my bearing supply house counter man to know. I don't think that the bike makers produce their own bearings they buy whatever they can from normal manufacturing stock so that means so can you. you are paying top dollar for oem because they already know what you need, have race teams and advertisements to fund. now if oem has a specific bearing made for them and have a parts lock on it they force your hand to buy oem

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It's not just the clearance to consider. There are also treatments to the races and the cage.

This is why oem spec bearings are often more expensive.

 

I recall a bit of discussion and information in the following thread.

 

http://www.thumpertalk.com/topic/1017152-running-c4-spec-main-bearings-on-a-yz125/page-2#entry10781673

The link is about crank bearings and they are special because of the thermo gradients in the crankcase, especially in 2Ts.

 

The OEMs do not make bearings, they buy them. Almost all Honda bearings are from NTN. Some Honda bearings are special purchase such as oversize IDs so the only source is Honda. All bearings have size markings that a bearing supplier can read.

Do a search on standard Metric bearings and you will find the labeling details.

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The link is about crank bearings and they are special because of the thermo gradients in the crankcase, especially in 2Ts.

 

The OEMs do not make bearings, they buy them. Almost all Honda bearings are from NTN. Some Honda bearings are special purchase such as oversize IDs so the only source is Honda. All bearings have size markings that a bearing supplier can read.

Do a search on standard Metric bearings and you will find the labeling details.

 

The OP includes crank bearings in the discussion so I posted the link as it is relevant.

All bearings will have numerous specific requirements depending on application. Heat, clearance, rpm, lubrication, service life are all factors in the equation.

 

Not sure if second part is relating to my post. If so I am well aware bike manufacturers source the bearings from bearing companies. I used the term "oem spec" to describe what the oem specifications for the bearing are, not because they made them. :thumbsup:

Edited by rmxdan

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Good point about "OEM spec"

If you are designing a wheel assembly the axle size may be an important consideration for rigidity, then you try to find  bearings to suit. What's available are speced for much higher loads and speeds than a motorcycle wheel.  Next decision is to buy the off the shelf (cheap) or spec a non standard bearing ($$).

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Counterfeit bearings are everywhere these days. I learned the hard way. Cheap bearings are cheap for a reason. Quality bearings cost more.  If you are not receiving your bearings from an authorized distributor (eBay) then it doesn't matter what the package says. You get what you pay for.

 

http://stopfakebearings.com/

 

Paul

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Counterfeit bearings are everywhere these days. I learned the hard way. Cheap bearings are cheap for a reason. Quality bearings cost more.  If you are not receiving your bearings from an authorized distributor (eBay) then it doesn't matter what the package says. You get what you pay for.

 

http://stopfakebearings.com/

 

Paul

Thx Paul.  The old adage of "Buy the best and expect a lot" has served me well in all matters and purchases.  I'll be at the bearing supply house counter on Monday.     

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avoid  anything made in China.     American, canadian,  german,  CZ.   all good  stuff. 

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avoid  anything made in China.     American, canadian,  german,  CZ.   all good  stuff. 

The only thing I buy from China is eggrolls -- certainly not anything mechanical or electronic. 

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For me personally, with 2t main bearings, I go OEM.  For trans., a good US or Japanese piece is fine.  For wheel bearings, I don't know if I've ever actually worn out  one - or even found a worn out one on bikes that I bought - that didn't fail because of contamination from water and dirt.

A lot of good info in this thread! 

I'll add that if I was rebuilding a street or touring bike that I planned on going 20k miles next summer, I'd feel better with OEM.

Edited by motoxvet

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No bearings aren't always bearings

I took my stator cover off to install a PVL on my 83 KX125. I have no more than 6 hours on my bike since total rebuild. I was blown away to feel play in the crank when I grabbed the rotor and gave it a shake. It's not much. Almost nothing. But it should be zero.

I used good oil and always had a clean filter.

I had cheap Wiesco main bearings for a KX85 I was rebuilding . They fit so I used them. So I blame the crap Wiesco bearings and myself for using them

I'm thinking of getting ceramic bearings to replace them

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Crank bearings are a somewhat unique application because of the thermo gradients inside the crankcase, the OEMs usually use a bearing with looser clearances to accommodate the temperatures, but they don't tell you the spec in the part fiche so safest is to use OEM. 

While Wiseco has a very good rep for their pistons they also have a bad rep for their cranks.

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Crank bearings are a somewhat unique application because of the thermo gradients inside the crankcase, the OEMs usually use a bearing with looser clearances to accommodate the temperatures, but they don't tell you the spec in the part fiche so safest is to use OEM. 

While Wiseco has a very good rep for their pistons they also have a bad rep for their cranks.

 for

I used oem parts to rebuild the crank,just used bearings that came in a wiesco box for the mains

I bought a Hot Rods main bearing kit off ebay, one of the bearings came in the package as the wrongs size

When I called Hot Rods the "Technician" told me that was the size they were given so that is what they packaged. No problem I said just send me the correct bearing. Unfortunately for me he wanted a credit card number because I he expected me to buy a third bearing because they packaged the wrong part

My point to mimic your point BUY OEM and don't buy Hot Rods

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