On sealed wheel ball bearings, the type of grease is unknown.
While on tapered roller bearings the grease spec is optional on a new bearing.

Have read that when repacking a tapered roller bearing the old grease should be removed or totally displaced with the new grease because not grease are compatible , since the thickner on the previous grease is unknown.

Fairly simple to gently remove the seals on a sealed ball bearing and clean out the the grease with paper towels and mineral spirits.

Noticed a wide selection of grease.

White grease, red grease, green grease, blue grease, black, amber, etc
High temperature grease, multi purpose grease, marine grease, synthetic marine grease, mobil 1 synthetic grease, symmetric with Teflon, Moly grease.
Sta lube/CRC, Mobil 1, Valvoline, mercury marine, omc, Warren, autozone, H-D label,

There a grease spec called drop point, which is the temperature where the grease transitions from semi solid to liquid.

Seems like most grease on the shelf is lithium soap based.
Either NLGI #1 or #2 spec, the higher the # the higher the drop point

So the question is what grease should be used on the ball or roller bearings.?
Maybe the ball requires a different grease than the tapered roller bearing?

 

THERE SEALED FOR a reason, there packed w/grease, mobil one is great, but thins out when hot, which in racing is awesome, but they can re-pack bearing as often as they want, as for you, I wouldn't worry, if there old bearings, change em, if you leave in, use a exact knife sharp point, carefully I mean carefully remove LIFT seal off, clean with denatures alcohol, and repack with a stable grease, not one thats going to thin out, and possibly run out...

 

Got some Timken ball bearings from Motion Industries yesterday
Two 3/4" x 1.781" OD x .61" wide & two 25MM bore x 52MM OD x 15MM (205PP).
ask what grease is packed in the bearings.
MI called Timken. Time's packed these bearings with Poly urea type grease.
Read up on poly urea grease and it is high end grease with high drop point temperature, good corrosion resistance, water resistance, apparently many forrmulations to urea.
Most poly urea grease are NOT compatible with lithium soap based grease.
Lithium soap is the thicker added to the lubricating oil, so the grease does not flow off the rollers.
Almost all grease found in the auto stores is lithium soap based, either NGLI #1, #2, etc, specifications
NGLI is a grease manufactures association that establishes the standards for USA made grease.
Some are complex lithium soap with a higher drop point temperature.
Found Mobil 1 synthetic at Autozone with drop point of 350F.

IF the grease is replaced in the new ball bearing, agree all of the original grease must be removed before repacking the bearing because a lithium based grease and poly urea are incombatable and the mixture decreases the drop point temperature of both types.

The rubber seals are much less difficult to remove than the new H-D ball bearings with the metal jacket. The sealed ball bearings are as not repackable , like the tapered roller type, since the bearing races and ***** can be damaged with the impact style bearing remover tool. The metal jacket on the new 25MM BB is distorted and scrap after removal.

Like the H-D removal tool that expands a collet to the inner BB race then pulls the bearing into a receiver cup with a threaded rod and nut. This procedure should not damage the bearing.

Once the bearing is removed probably less trouble and cost to just replace the bearing rather than repack the existing bearing.

When H-D changed the 25MM BB(-A) from double rubber seal to metal jacket/rubber seal ,(-B),tried to find the -A just two months after the change, no luck.
Conclusion: H-D dealers are replacing a whole bunch of wheel bearings.

 

Contacted "All ***** Racing" that supplies ball bearings for about every bike wheel on the planet a n d ask what grease is used.

The response was Chevron SRI 2, which is poly urea thickened based grease formulated for high temperature up to 300F and high speed 10,000 rpm ball bearings and roller bearings. Chevron grease is made in the USA , while the All ***** bearings are Chinese sourced? Something d on especially not add up?

 

When starting this thread had no knowledge of grease.
Have been researching this subject almost full time, since.
bought four different types of grease
1. Blue colored marine by Sta Lube(CRC), aluminium soap based thicker, smooth to lumpy texture, drop point 500F
2. Red colored , super tech(warren oil blender), lithium complex soap based thickner, smooth like butter, drop point unknown, extreme pressure (EP)
3 Red colored, Lucas Oil, lithium complex soap based thickner stiffer than Warren oil grease, drop point 540F
4. Green colored, Lucas Oil, Polyurea thickner, drop point 540F, also meets John Deere specification

Got four wood paint stirring sticks and placed a big glob of grease on the end of each that covered the width of the stick
and placed the sticks vertical up against a block wall, outside in the sun. Yesterday it's was 105F ambient here in central CA.
purpose was to measure the slump
Also noticed the oil release stain from grease on wood stick, Warren oil had the highest amount of oil release to the wood.
getting tub of Mobil 1 synthetic grease , drop point 350F at autozone to test slump.

John Deere explains the application lists the specs on the their Poly urea, lithium complex soap & conventional multipurpose lithium soap grease.
JD rates the grease
Polyurea-best
lithium complex- better
lithium multi purpose- good
appears that polyurea is the latest technology in grease for spherical and roller bearings.
Polyurea has longer life compared to lithium and contains a higher % of lubricating oil compared to lithium, no metal based soap

Removed the double rubber seals on several H-D ball bearings with HD number engraved on inner race, both sides, all had the plastic cage.
The new -B, 25mm x 52mm OD x15mm have a metal jacket. This metal jacket maybe more difficult to remove than the rubber seal type without distorting.

Agree that removing the ball bearing will compromise the integrity of the bearing, if using an impact tool like, Pit
Prefer the expanding collect type using bolt , then an all thread and nut to draw the bearing into a cup receiver.
The H-D bearing removal tool is designed that way.
Still consider the MC ball bearings as remove and replace., not repack , like tapered roller bearings.

appears the new Timken ball bearings are packed with Polyurea grease.
Polyurea grease and lithium soap base grease are not compatible, the grease mixture converts to liquid.

Chevron SRI NGLI 2, synthetic, Polyurea is one of the best for ball bearings with 500F drop point
​​​​​​Like to find a source for small retail quantity of this grease.

​​​​​Second choice is Lucas Oil or John Deer, green colored, polyurea grease for pre 99 , Roller bearings

Noticed H-D has specialized grease for the steering head and wheel bearing grease, but formulation is unknown.

 

Just received a set of timken 205PP bearings, say made in USA, am hoping better quality than the HD ones, had a rear fail 150 miles from home last week only 25K miles. pulled them earlier, were really in there tight. will freeze new ones over night and warm hub slightly before install. from most of reading, one installs the disc side first on the rear, have read over service manual, states nothing about install sequence on rear, just front.
will be inspecting frequently after that.

 

25k seems like a whole bunch of miles on a rear ball bearing, must the earlier 21mm width BB.
Timken 205PP is newer 15mm width,but will fit 2000-2007 hubs with special shim under rotor side BB.

 

the bike is a 2014, has the 15mm wide bearing.

 

Way ahead of the curve on rear wheel mileage for 15mm wide BB.
mounted on XL , FX, FL?
weight makes a difference and smooth roads

 

Wheel Bearing my preference is mobil 1 syn grease or Green Grease, that stuff while sometimes a pain to find is awesome.

http://www.greengrease.net/