I installed tapered roller bearings in my steering head about 6 weeks ago.
My new bearings came in two pieces for each of the top and bottom – the race and the rollers (total or four pieces). There was also a big fat old washer (which I found intimidating and confusing, at first.) My Chilton manual was helpful, and to some extent so were the instructions on the box the new bearings came in.
I was careful taking out the old ball bearings and races because someone in a discussion on this site suggested that was a smart thing to do (because you might find them really helpful putting in the new ones). As it turned out I didn’t need them, but during the process of putting in the new ones I could see where having them could be a lifesaver…..
I guess I sort of did it the way Paul describes. I had two steel disks the same (two) sizes as the races – top and bottom. Each disk had a 3/8 inch hole in the centre for a threaded rod. The rod was long enough to extend a few inches beyond the frame steering head on both top and bottom. I slipped the rod through the steering head and held it there while I slid everything onto the rod in the right order. Then I put on the steel disks followed by good, thick washers, and 3/8 nuts. I tightened the nuts until everything was finger tight, checked the alignment carefully, and then I slowly and carefully tightened the nuts until everything was seated tightly against the steel stops inside the head. After that, when I loosened off the threading, the bearing packs fall (or lift) right out. (The way my new bearings were made, I could see where it is possible to make the mistake of mixing up the parts - make sure the smaller bearing pack goes in the smaller race.)
Then I threaded the rollers and the bottom washers on the steering stem, and passed it through the head until I could catch the appropriate thread at the top with the steering top head thread. (How much of that threading comes out past the top bearing is the determining factor in whether or not to use the (dreaded) washer that came with the roller bearings. I guess the roller bearings I purchased are a little thinner than the original, three piece bearing set(s) they replace, so to get the stem positioned properly for the top threading (which is a two tiered arrangement) some bikes need the extra spacer. I wouldn’t trust anyone but myself or a licensed Honda mechanic to tell me whether or not I need that washer. I didn’t know, but it’s actually pretty easy to figure out once you have the new races installed.
A few last things (I hear a big sigh of relief right through my computer) –
I tried freezing the bearings. I’m pretty certain the installation process took me far more time than it took the bearings to expand back to normal. I like the idea though.
Before I did anything, I put a grease fitting on the frame head. I’ll probably be too old to ride by the time it comes in handy, but I did it anyway. If you decide to do the same thing, please be careful about where you put the thing. The mistake I almost made (too close for my comfort) was to put it in a spot where it would interfere with the 6 pin main ignition key plug (which turns across the head with the steering). I was all proud of myself for figuring out how to put in a grease fitting and felt pretty stupid a few days later when I started putting the front end back together and it looked like it was in the way (and not many spots on that steering head would be in the way.) I lucked out though, and it cleared by a few mm’s. Yeesh! Talk about pride before the fall.....
I thoroughly cleaned the head stock, gave the place(s) where the bearings sit an emery cloth once over, and I put a super thin coat of grease on the steel, just where the bearings fit, before I tightened the threaded rod.
I don’t know, I hope you can find some of this useful. I’ve got a bit more to say, but I’ll do it in another post.
All the best…..