Help replace stem bearings with taper rollers

Hi guys,
I've bought myself a set of roller bearings to replace the old knackered bearings. The steering was being reluctant to turn and sort of had a stop in the middle. The lower bearing was a pain to remove but finally managed to prise off using two small chisels from two opposing directions. It took 3 hours of tapping, hammering and prising but finally obeyed. Now to put in the new 2 piece taper rollers. I thought of putting the lower stem in the freezer to retract but since the roller part is one piece with its ring I'm afraid of putting that in the oven to expand.

Questions:
1, Should I put grease before installing it or after?
2, Does the OEM Lower dust seal fit the new bearings, I had to rip off mine to remove the lower bearing.

[Spanner Man]

Good morning.
Clean the stem with fine wet & dry, & remove all the inevitable nicks that have probably occured, as it's very important that the new bearing sits flat against the bottom yoke.
Then grease the inside of the bearing & the stem. The best thing to use to drive the bearing on is a tube of the correct diameter, if however you have no such thing to hand, you can use a long drift if you're careful, but you must make sure that you only tap on the edge if the bearing inner. You may have to file or grind a drift to a wide but thin tip. Tap gently & evenly around the bearing to get it started, & you should find that once it's started it'll tap home nicely.
You cannot use the original seal as it will foul the bearing itself, your new bearing will either have a built in seal or it wont. Once installed, pack it with a good quality high melting point grease.

Cheers.

I stumbled upon a problem.

I've installed the lower taper bearing without a dust seal as I've destroyed the original upon removal.
I've found that the dust seal thickness has the second purpose of providing some clearance.
Now the lower yoke is grinding against the head stock!!!
I've got to buy a new bearing and start over, this time I'll put in a 42mm wide washer with an inner 30mm hole to lift the bearing up. At the same time this will act as a sort of dust cover. Can't understand how no-one posted anything about this problem whilst converting to tapers.

[northwind]

I didn't have that problem...

Originally Posted by northwind

I didn't have that problem...

Nor me.

[Spanner Man]

Good morning.
The original bottom bearing has an overall depth of 17mm, as does the 32006JRRS Koyo bearing that I recommended. The original dust seal measures .42mm thick.
As the clearance between the bottom yoke & the frame is much greater than .42mm as standard I can only conclude that the bearing you have fitted must be under 17mm deep by a fair margin.
Did you use those pattern bearings that you had? Or did you purchase the Timken bearings that you spoke about in your PM's to me?

I'm going to say that I object to the tone of your post, (whingeing springs to mind). Other members besides myself gave good clear instructions as to how to remove the bearing from the stem without destroying the dust seal. You obviously ignored them!

I'm always on about the importance of using quality replacement parts, & it looks as if you have been caught out by using inferior/incorrect ones. Which is nothing to do with me, or any of the other members that gave you sound advice in good faith. So Zip it!

Cheers.

[21QUEST]

Originally Posted by zunkus

I stumbled upon a problem.

I've installed the lower taper bearing without a dust seal as I've destroyed the original upon removal.
I've found that the dust seal thickness has the second purpose of providing some clearance.
Now the lower yoke is grinding against the head stock!!!
I've got to buy a new bearing and start over, this time I'll put in a 42mm wide washer with an inner 30mm hole to lift the bearing up. At the same time this will act as a sort of dust cover. Can't understand how no-one posted anything about this problem whilst converting to tapers.

Zunkus mate, simply put, "if there is a dust seal, it's there for a reason ie err to protect from dust etc".....unless of course the replacement bearing has an integral dust seal.

If I were you, I'll source a dust seal as a plain metal washer won't suffice(IMO) for the purpose of keeping the pixies away. Heck, PM me your address and I'll stick on in the post for you......if you are prepared to pay(via paypal) for the postage

Perhaps you were a bit impatient......


Ben

[northwind]

Originally Posted by Spanner Man

I'm going to say that I object to the tone of your post,

Fair play though, it's very easy to get annoyed and discouraged when you hit a wall like this. It's not like he accused us all of misleading him, he said he can't understand how nobody mentioned it. Now, he probably does.

Sorry for offending you guys. Not my intention at all. You've been great help and I'm surely not a whinger. I've made a stupid decission in not putting in a dust seal. It cost me another bearing and machining out a dust seal at a machine shop eventually. I'm not one to go cheap on my bike and yes I've used Timken. Now after these mods the front fitted nicely and is feeling great. Again sorry for hurtin your feelings guys. Totally my bad.

Zunkus, you really shouldn't have had a problem without the dust seal. I destroyed mine during removal but didn't replace it as the taper roller bearing has an integral dust seal. I must have 1.5mm clearance between the yoke and the headstock.