Radial and axial load calculations for MRC bearings HELP

[agrady1995]

To whom it may interest.

I am about to do the double bearing mod on my 97' valk. I was interested in trying to calculate the life of the bearings using this manual:

https://www.skf.com/binaries/pub198/Images/0901d1968024f8c3-M190-730_MRC_Engineering_Handbook_2015_tcm_198-279709.pdf

Pages 105 and 106 go through the bearing equation and examples for bearing life.
I tried to calculate this, estimating a speed of 100MPH (1056 RPM for a 16" Radius tire) and with a static axial load of 950lbs (weight of whole bike plus me) and tried to BS a radial load, but was unsure of what to put.


When my Bike did a 180 degree turn (locking rear brake and sliding) I caused the failure of the left side bearing. I am going to replace this with a MRC 5204CZZ bearing on each side, and omit the left side seal.

I was hoping someone could help me to understand the caluclation required to get a general life of the bearing...

Thanks!

[John Schmidt]

You also have to cut down the spacer on the left side to make room for the double row bearing. Can't help you on the bearing life, just know most who have done the mod get a major increase in life over the single row.

[Jess from VA]

Just buy what is called First Tier bearings.  I used OE Hondas.

And never use a pressure washer on the bike. 

[Jims99]

I have done the bearing mod on all 3 of mine. The first was over a year ago and the last one I'm still putting together. Replacing as I need tires. It's not hard, just need to have spacers cut down, my local machine shop does it for $5 each. I'm sure with it being a larger, better bearing it will last much longer. There are a lot of people with 100k on original bearings, so I would think these are the last ones I'll have to do.

[agrady1995]

Thanks for feedback. I have a surface grinder at work so I plan to take of t
Exactly how much I need from my spacer. I just was hoping a math nerd might see this.

[98valk]

Thanks for feedback. I have a surface grinder at work so I plan to take of t
Exactly how much I need from my spacer. I just was hoping a math nerd might see this.

https://www.valkyrieriders.com/shoptalk/5204_bearing_mod.pdf

[98valk]

In this link it mentions taking an extra .010 off the spacer....dont do it. This spacer sets the position of the track of the ball bearings in the races......this amount might push the tracking too far from nominal....

so the shoptalk info is incorrect?  it should be updated.
thanks for the info   

[Jess from VA]

In this link it mentions taking an extra .010 off the spacer....dont do it. This spacer sets the position of the track of the ball bearings in the races......this amount might push the tracking too far from nominal....

The linked article says the machinist who cut down the spacer for the author recommend cutting an extra .010 off.  The author of the link said that was a bad idea and didn't do it.  

There is a Nilos Ring one could get and sister to the outside of the bearing to give it a better weather seal, and that might justify an extra .010 (or something).  I didn't do it (on either of my two bikes), and don't know anyone who did.  And have not read of one single double row bearing mod failure.

Lay off power washers.

Nilos Ring

[Avanti]

I use the Nilos Ring.

[Jess from VA]

Did you cut more from the spacer for it?

[Rio Wil]

In this link it mentions taking an extra .010 off the spacer....dont do it. This spacer sets the position of the track of the ball bearings in the races......this amount might push the tracking too far from nominal....

so the shoptalk info is incorrect?  it should be updated.
thanks for the info   

RATS.....this comment was a big brain fart.....I removed the original.....sorry.....

[RonW]

Shoulda used the strikeout feature instead. For example ..... The next day even I can't understand what I wrote the night before.




Anyways, regarding how much to shave off the length of the spacer, X Ring stated in his Shoptalk article,.....

"The machinist recommended removing another .010" to be on the safe side. (Editors Note: I don't like the idea of removing an additional .010".
If the bearing is .260" wider, remove exactly .260" from the spacer. )"

Also, if adding a Nilos ring, X Ring stated in this post (2011), he didn't think it necessary to shave off extra for the thickness of the Nilos ring. Nilos ring is .018 thick.
There's a debate whether a sealed bearing even needs the Nilos ring.

[Avanti]

Did you cut more from the spacer for it?

Needed to look way back in my records.

machine wheel spacer  0.615 with nilos ring or 0.625 no ring

I machined mine to 0.615 and use the nilos ring.

[LJVALKYRIE]

I've been watching this thread and have looked at the original post with great interest.
I am a Power Transmission Specialist for Motion Industries. The largest Industrial Distributor in the world. I work directly with SKF reps, Timken reps etc.  I've been doing my job for 22 years. I can talk and visit about bearings with this group for hours and probably make some jaws drop from what I have seen with customers.  I LIKE the idea of the wider bearing on the brake rotor side. There is absolutely zero reason to use a Nilos ring if a 2RS or rubber shielded bearing is used. A ZZ or shielded bearing is redundant in this application.  When I replace my bearings, I will use a SKF set of 2RS bearings and will machine down the spacer and put it together and forget about it. I have seen some brutal places where 2RS sealed bearings are being used and holding up just fine, this application is gravy on these seals. 

[RonW]

There is absolutely zero reason to use a Nilos ring if a 2RS or rubber shielded bearing is used.

Okay.