Taper roller steering bearings - trials and tribulations

[TiBolts]

Hi all. I have some Pyramid Parts taper head bearings which came with lots of new bits that I got with my Z1000-A1 bought-in-bits project.
These come with a large but thin washer with a rubber lip round the edge to act as a grease seal. Now I haven't fitted any of these bearings for about 30 years but I used to sell a lot of them back in the 80s and don't remember them ever coming with a grease seal.
So anyway I fitted the seal/washer then the lower bearing then put the bottom yoke in to have a look (I'd already fitted the bearing seats into the frame, top and bottom) and it seemed to me that the bottom yoke was a bit too low - it wasn't hitting the lockstops enough, and to me it looked like there was not enough thread sticking out of the top to allow the top washer and special nut to go on properly.
So I removed the lower bearing from the bottom yoke... destroying it in the process and removed the washer - which was actually quite thin, so I'm wondering if I'll still have a problem without it). And now I need a new bearing.
Questions:
Is there much, if any, difference from the cheaper ones and the Japanese ones, or does anyone have a recommendation?
What should the dimensions be of the bottom bearing?
Do people generally run these without grease seals? (I'm assuming the OE one is no good as it's designed to go around the conventional cup and cone style bearing race).
Anyone had similar experiences?
Cheers

[Philippe]

Hi Tibolts
the tapered head bearings are known as SSK400 type and I allways buy them as a set.
As far as the dimensions are concerned I can't give you any, I never measured them...
When installing them on the lower yoke you start with the thin metal washer, then the rubber seal and then the lower bearing.
Make sure you put enough grease in the bearings before installing them!
To put the lower bearing on the lower yoke, use the shell from the old roller bearing on top of the new tapered bearing in order to prevent damage and slide a hammer along the steering stem, hitting the shell of the old roller bearing. Use the same method left and right, front and back to make sure the new tapered bearing sits even on the steering stem. Make sure that the rubber seal is free and that it doesn't get trapped between the thin washer and the bearing. When the bearing sits at the bottom of the steering stem and you tap on it, you can hear a clear sound. As long as you don't hear that "clear" sound the bearing isn't sitting deep enough.
As far as the two pins on the lower yoke are concerned: are you sure they weren't cut down in the past by a previous owner ?
If they were, it's normal they barely touch the lockstops.
Are you sure the lower bearing seat sits deep enough in the frametube? Here again you can hear a "clear" sound when it's deep enough.
Good luck!
GrtZ
Philippe

[warren3200gt]

Might be obvious but I've seen it before so just checking! You did remove the upper cup of the lower ball race from the frame steering headstock? If not this would explain why the lower yolk was sitting so low and why there was so little thread showing at the top.

[TiBolts]

Thanks for replies.

When I bought the bike, it was already almost completely in bits - well, the engine is complete, and the forks were together although the stanchions were badly pitted. The headraces had already been removed. Now the frame's been cleaned up and powder coated, and I've removed the masking tape that the coaters put in the headstock etc.
Yes I did fit the bearing fully onto the stem and into the headstock - I know what you mean about that 'clean' ringing sound you get when it's fully home...I had the frame upside down and supported on wooden blocks, so I could give it a good whack!
In fact the lower outer race is quite a way up the headtube - my intial worry was that the yoke would go too far up and scrape on the bottom of the headstock! But no.
I think I'll be Ok with a new bearing. But I definitely won't put a washer/seal underneath it - apart from anything else the one supplied was a bit of a loose fit - ie it was about a millimeter bigger than the internal diameter of the lower bearing.
And the lockstops don't show any signs of being tampered with.
Hmm. I will report back when I've got another bearing, or set.

[z1bman]

these are the dimensions
Upper 30x48x14mm Lower 30x52x17mm