Front wheel bearings

I never imagined there were so many bearing types and materials. I just clean and lube up the originals i have and hope for the best.
The Roger Barlow article you linked was A+, thanks for posting. There are many ways of tightening up these front ends, dry ice chilling bearings, metal spraying and regrinding tolerances.
I just figure I will go slow around turns, keep the shocks filled up and never try to go a hundred miles per hour.

Hi,

It?s been a while, and it seems the topic of wheel bearings is a bit dry for this list? not too much interest. I will close the thread with this post.

I got started investigating this after reading an article that suggested that front wheel bearings are a known weakness of the Cord 810/12 design. See the article at:

[url:28y1sfpm]http://www.jsasoc.com/Family_archive/Archive/barlow/escape%20road%205-2-88%20Cord%20810.pdf[/url:28y1sfpm]

While the article suggests the dual row bearings are two inches apart, one manufacturer places the widest bearing surface only .884? apart. Less than one inch!

In any case I have completed my look into what current bearing manufacturers are producing. There are a variety of designs that fit the application and a number of options to be considered. To keep things short here are some suggestions

- Avoid polyamide cages. Brake heat may cause them to degrade.
- Use Conrad fill style bearings only. These can be identified because they have no filling slot. This goes against some of the part numbers listed on an ACD document. Caution is advised.
- The bearing should have both inside and outside shields. These are selected with the codes at the end of the bearing number.
- Bearings that are sealed with permanent grease could be used. Again this is selected with the suffix codes. In some cases these are more modern designs with FWD in mind.
- Various grades of bearings are available. Some with higher axial and radial force capability.
-Initial ball contact angle sets the trade off between radial and axial capability. Certain series of bearings have much greater capability at almost no additional cost.

I hope all this is of some use. One thing I have not found yet is if Cord used metric dimensions for this application. All the bearings I found are metric sized.

Hi,

I spent a bit of time looking into 810/12 Cord front wheel bearings which has generated both information and questions. The bearings for the front wheel are a dual row angular contact design. The base part number is 5209 which specifies the basic width and diameters, and the following parts were suggested in an ACD guide I found.

Fafnir 5209 WD Loading notch construction, single shield face opposite notch.

New Departure 5509/55509 Conrad construction, no loading notch. Changes up to a double shield Conrad style.

MRC 5209 KF Loading grove/notch construction

BCA 5209 S Details are not clear due to conflicting info. S suffix is for a single shield design. This series is termed ?light? series. This is a Conrad design made to inch dimensions.

Hoover (NSK?) 5209 FF Conrad construction. Other details not available to me.

As I understand it, Conrad construction is where the balls have gaps between them. They are filled through one side then moved to equal spacing. A cage is then snapped into place to keep the space. The notch / slot bearing construction gives a higher ball density and thus larger radial load rating.
One other interesting thing is that some manufacturers seem to have converted the bearing size to metric. This would result in a loose fit on the inside hub. I have some questions for the experts?

Have many members experienced front wheel bearing failure? How do they fail?

I know the slot construction suffers when axial load is applied (in a turn). I believe this style would be best avoided. The Conrad construction however, doesn?t hold near as much radial load. Which construction is recommended for wheel bearing replacement? Is there a brand and part number that has been found best?

If slot construction is thought to be best, is the slot installed on the inside or outside?

Is no shield, single shield or double shield design suggested?

Where loose fit of the bearing on inside or outside is an issue, is ?hard chrome? recommended to build up the surface? If so are there any problems with cracking due to hydrogen embitterment?

Thank you for your patience with all the questions. I hope someone will explain what best practice is.

Cheers,
Tom Hussey