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Stem bearing cage question

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I just got my stem back from having a new bearing pressed on. I thought the cage that holds the bearings would spin freely. It appears like the cage sits slightly above the collar and and does not budge. I asked the counter guy if he thought it would turn freely and he thought so but then came back after asking the tech in the back room and said it is as it should be. My gut feeling is that it should freely spin and should be pressed of again.

Stembearing.jpg

I cant turn it with my hand. What do you think?

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I've just done an USD conversion bearing assy, and indeed the cage should spin freely. For my first press attempt it did not, the cage was pressed on the seal and could not spin. In a good bearing/seal combination the seal has a groove where the cage has space to spin free, and the bearing inner part is pressed again the metal plate of the seal.

Looking at your image, that seal does not seem to match up with the bearing.

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Hey Wallander thanks.

I came back down to the shop and messed with it for a while. I ran a jewlers screwdriver under the lip of the cage to see if it was just the bottom lip of the seal hung up. I also heated the tripple and tried to move the stem (hammer) a bit to see if that would free the seal. I don't think I moved it at all but the cage sits further down and now spins. I wish it spun like the other one does sitting on the bench. I guess next is to install the stem and top tripple to see if it feels catchy or has a drag.

I wish I had a press so I could have done it, not that I wouldn't have had the same result but that I wouldn't have paid to be told "that is how it is supposed to be."

The same shop did the bore and it seems like a good pattern and measures according to the instructions for the gap between cyl & piston. I have an inexpensive digital mic and have checked several times. I am having the valve guides put in at another shop and may see if they could give it a quick look.

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One mod that used to be common, was putting a grease zert into the stem, and filling it with grease. Rust is usually what kills stem bearings, and keeping it full of grease helps eliminate that.

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I saw the one RockJocky did. With the frame bare it was hard to visualize where would be best without seeing it.

I installed stem on the frame to see how it was going to feel & seems ok to go. Having a zerk would make life easier and become just another part of the ride prep.

As for the seal, it is what came with the all balls kit. The widest point is toward the widest point of race. I just think the tech who pressed the bearing on didn't care if his work met minimum expectations (that it work). It will make a good example in our employee manual to demonstrate how easily we can loose our customers confidence, trust and business. .

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I think there is no wrong way to press on the bearing and seal, the bearing inner part will rest on the seal metal part and the cage should spin free from the seal rubber part. If it's not, the seal is not okay for the bearing. When you will assemble and set the bearing torque the cage rubbing around the seal will just get worse.

This is the theory, but as it's already pressed on, assemble quickly the whole triple-tree and see how it works.

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