53K Wheel Bearings

[Mayday53]

I appreciate any suggestions for a reliable front wheel bearing replacement. What do you guys use/recommend?

Original Bearing in 53K (according to original owner)

53K Front Bearing-External side.jpg (68.49 KiB) Viewed 16698 times

Original Bearing in 53K (according to original owner)

53K Front Bearing-Internal side.jpg (63.69 KiB) Viewed 16698 times

Spacer/bushings and Bearing

53K Front Bearing - Spacers.jpg (98.99 KiB) Viewed 16698 times

[Mayday53]

I went to local shop and found a couple that are "6203" bearings. The micrometer shows both with the same ID as the original and an D about .02" larger; will that be ok when pressing them in the hub (I am assuming they are pressed in with a lightweight press).

As usual...your help is appreciated!

[JohnF]

If the bearing truly is.020, that is twenty thousandths bigger, it will not work at all. If the dimension is actually .002, two thousands bigger, you may be able to press it in but don't overly force it. Make sure the inner race rotates freely.

Before going to far, go to JP Cycles website, or Masclassic.com and look up parts you need. JP has a nice lookup feature where you plug in your scooters info and select save this search and show only parts that fit. It will give you a very nice breakdown by section.

Good for research and good source for parts. V-Twin is also good.

Getting a Spare Parts book for the bike is invaluable for researching and locating parts. Bought a spare through EBay from a "medical something" source in MN at a reasonable price, think $15.00. A reprint of 52' to 62' or something like that.

[EKHKHK56]

The last set I got was from a major bearing supplier like Motion Industries. I would think the exact bearing by measurement would still be available from large bearing supply houses.

[thefrenchowl]

All these K/KH/Sportster wheel bearings are DIN standard metric bearings...

Buy at your local engineering shop for low NON HD prices!!!

Patrick

[John R]

Your bearing stockist should be able to supply a direct replacement but neoprene seal both sides. The original were metal shielded one side, open the other - open side facing in so that grease can flow from the centre nipple, and shielded from dirt on the outside. I'd go for the neoprene sealed lubricated for life type. No disadvantage that I'm aware of, keeps dirt/water out better and saves greasing.

Steel shielded have the advantage of a no-contact shield so no friction and potential for heat build-up and are usually now used in high-speed applications where the slight friction of a neoprene seal could build heat and cause failure of neoprene. At around 1000rpm max, wheels are definitely not high-speed applications!

Good luck,
John

[Mayday53]

Your bearing stockist should be able to supply a direct replacement but neoprene seal both sides. The original were metal shielded one side, open the other - open side facing in so that grease can flow from the centre nipple, and shielded from dirt on the outside. I'd go for the neoprene sealed lubricated for life type. No disadvantage that I'm aware of, keeps dirt/water out better and saves greasing.

Steel shielded have the advantage of a no-contact shield so no friction and potential for heat build-up and are usually now used in high-speed applications where the slight friction of a neoprene seal could build heat and cause failure of neoprene. At around 1000rpm max, wheels are definitely not high-speed applications!

Good luck,
John

John, are you saying by placing in a sealed bearing the front axle will not need to be greased? Also, the ones I received are sealed with steel casing on both sides, automotive industry tailored design. Based on your experience, do you think those are a good idea over the neoprene sealed bearings?

[John R]

In practice there will be little difference. Seals, metal or neoprene, are designed to keep grease in and water/dirt out. In extreme road conditions neoprene should be better. Neoprene sealed bearings weren't yet developed in 1952, so best at the time was metal shielded. Harley used a shield on one side only so that grease can be pumped through via the grease fitting, excess finding its way past the clearance in the non-contact shields, also helping to expel any water (but potentially also into the brake drum, so excess had to be checked for and wiped-off).

Double seals also keep the 'grease for life' not just in the bearing, but in contact with balls, cage and tracks. You've seen old open bearings where the grease has been forced outward and everything is running close to dry.

You could ping out the shield on the side that will face inward so as to be as original, but I wouldn't bother. The outer grease seal means that dirt and water are unlikely to even get as far as the bearing. With metal or neoprene seals on both sides of the bearings you can cross-off greasing the hubs and checking for surplus grease from your mainenance list. More time to enjoy!

My perspective is that in 1952 Harleys could have used double-sided metal shielded bearings and eliminated the grease fitting with no loss of reasonable service life. How many grease fitting on modern machines? None, due to neoprene sealed bearings.

John

[starcain]

For what it's worth, I just bought front and rear wheel bearings for my '53KK. I went with the original style metal shielded on one side and open on the other. MRC-203-SF for both front bearings and for the left small flange side of the early K hub. The double row ball bearing used on the big flange sprocket side of the early K hub is a MRC-5203-SBKF. I got these through LocateBall Bearings.com for a total of $65.25 with shipping for all four bearings. The big bearing was about $31.00 and the smaller ones $8.00 each. They had them in stock and I got them in three days. I thought the prices were quite reasonable and I am very pleased with their service.
http://www.locateballbearings.com/
1-800-409-3632

[Mayday53]

Good deal...I got mine for about $25 each at a local automotive shop and they fit in slick as a glove. I am glad you found a solution as well.