Jump to content
Sign in to follow this  

Dont spin your bearings... (Steering Stem Question)

Recommended Posts

My steering stem bearings have felt fine up until the bike sat for a couple of weeks while i was adjusting the valves (waiting on parts). When i was putting the top end of the engine back together, i noticed my wheel was lightly stuck, but would free up and act normal (maybe a little notchy) after you turned the wheel. So today i pulled the steering stem out and was cleaning the top bearing. It looked really rough, and probably needed replacing but i was going to clean it up and put it all back in to see how it felt once on the bike. Well, i know you're not supposed to spin the bearings with an air compressor, but i figured they're already rough looking, i need to clean them as good as i can. So they start whistling, and the pitch is getting higher and higher and then all of a sudden the bearings dropped off of the inner race and hit the ground. From there, they then proceeded to roll at a very vigorace pace across the yard about 25-30 feet before they hit the bricks going around a flower bed. Then they bounced about 5 - 10 feet in the air, and landed making a 90 degree turn and went about 15 feet across from where they just hit the flower bed, through a hole the dogs dug under a tree, and onto the drive way. Somewhere around the time they hit the drive way the bearings started flying out of the metal piece that holds them all together. It still went another 25 feet before it finally came to a stop in a pile of bearings, and the piece that holds them all together, which is now warped. So me and my brother are watching the whole thing, our faces were :thumbsup:.

So anyway, now i need to replace the bearings, seals and the races inside the frame. My question is, can i replace the races inside the frame, and the bottom clamp bearing myself? I need to get this done spending as little cash as possible. Also, is there anything special about the bearings, or could i get them at any bearing shop?

Share this post


Link to post
Share on other sites

Glad you guys weren't clipped by the runaway beairing cage. THAT woulda left a mark! :thumbsup:

Here is a link wrooster's write up on the faq. It might help you with re-assembly.

http://www.thumperfaq.com/steering.htm

I'm pretty sure that there was a thread on here a week or two ago about removing those steering stem races, and several good ideas were presented. Try a search.

Share this post


Link to post
Share on other sites

I replaced the steering bearings and races on my 02 YZ 125 last year with simple hand tools but it definitely took some elbow grease! Be sure to have something to warm up the steering stem ends before knocking out the races and a good tool to get ahold of the races. Pivot Works has the complete package.

Share this post


Link to post
Share on other sites

I'm pretty sure that there was a thread on here a week or two ago about removing those steering stem races, and several good ideas were presented. Try a search.

Pivot Works has the complete package.

Thanks for the replies. I'll check out that link and see if i cant find the thread you're talking about. It doesnt look like it will be as hard of a job as i was thinking it might be. I'm looking at pivot works bearings in a dennis kirk catalog right now. $47.99 for everything i need. Not a bad price at all.

Share this post


Link to post
Share on other sites

Yeah.

If you look for a thread no older than 2 weeks by me on replacing bearings there are a LOT of good tips in there.

I was able to do it in a day.

The two most difficult parts were getting the races out, getting the bearing off the stem and back on.

I ended up doing it all with a punch basically.

If I were to do it over again, I'd probably give it 2 days so that I could take the stem with bearing attached to the shop and have them press it off and then immediately press the new one back on. It would save a LOT of work.

Use your old races to seat the new races with a hammer... deadblow didn't work for me but I didn't heat the the head up... although I did freeze the races.

An 8 or so inch punch (real punch... not alignment tool will help with removal but there is a only a VERY thin lip that you can get at to start punching out the races AND the seat protrudes so that you actually can force the punch through the edge of the seat (then you have to file/grind etc to get the burrs off so the new race will seat properly.)

A biggee is that while the bearings and races look the same they are NOT. Pay attention when you pull them... it will save some head scratching later. Note that they are sets so make certain you press the correct one back on the spindle.

One last thing is someone (maybe a different thread) recommended a bearing packing tool. I got one for about 10 or so bucks and that thing is pretty trick. Make sure you pack the bearing that will be pressed on the shaft before you take it to the dealer.

Oh yeah, the punch ended up not working for me totally so I ended up purchasing a large elcheapo screwdriver and grinding it down and it allowed me to barely squeak by but I almost gave up many times cause it didn't want to grab the edge.

In the thread mentioned above there were some good solutions on how to take a piece of pipe, cut it down and make a tool etc.

There was also another tip about a tranny seal/bearing removal tool and slide hammer solution. If you've got some bucks that may be the solution to removal.

Wrooster also has some good info on grease etc.

If you get in a bind, PM me and I'll try to help. God sakes everyone here has helped me out enough. :thumbsup:

Share this post


Link to post
Share on other sites

As someone with over 30 years as a professional wrench, I have seen a lot of bearings spun with air (after enough beer, I will even admit to having done it myself. There are a number of things that can happen to a bearing when you do this, and I don't recall any that are good. One of the things I saw was a nice young fella who had a little ball bearing wound up to around 25,000 rpm or so when it siezed. It dislocated two of his knuckles and tore off a lot of skin. They sometimes explode, too, so watch out for that. :thumbsup:

Anyway, here is a tip for driving any taper roller bearing assembly onto a shaft. The problem is that in order to run the bearing on with the least force, it should be driven or pressed with a tube that has an inner diameter large enough to pass over the shaft, but small enough that it will not contact the roller cage. The cage, you see, generally sticks up higher than the inner race, and if it is pounded or pushed on during the bearing installation, it will be damaged, and the rollers will not run straight.

So, make a bearing driver out of your old bearing. Use a pair of diagonal cutters (wire cutters, dikes) to break the cage open, and remove the cage and rollers, so that all that remains is the inner race. Now, position the new bearing, place the old inner race small end down against the small end of the new bearing. It will perfectly fit the face of the bearing without touching the cage. You can now use a much less precisely sized piece of tubing (or even turn the whole thing over and use a hole in the work bench) to drive the bearing in place.

Quite often, the old race will run part way onto the part of the shaft that fits into the bearing and get stuck there, but they are easily tapped back off with a punch. :devil:

Share this post


Link to post
Share on other sites

grayracer-

I'm gonna pull my old one apart and see if it would have worked for me.

My concern was, number 1, as you mention getting the old bearing stuck on the shaft, and number 2, having the inner race of the old bearing come in contact with the "raised" part of the inner race of the new bearing. Like you say, there is a very thin area that is DEFINITELY the inner race and a part that is raised above it that kinda rides on the inner race. I believe what you're saying is that once the bearing is disassembled that there will be a thin side to the race that will NOT come in contact with the part we don't want to touch.

Share this post


Link to post
Share on other sites

When I bought my WR I pulled both wheels steering stem & swing arm apart , I gave all of these parts a proper greasing as they come from the factory with the minimum amount of grease on them .There good quality bearings but no bearing no matter how good a quality they are will last long with out a fair amount of top quality grease . I used Shell Alvania EP(LF)2 .grease Its a good grease to dispurse water and is rated for high speed and loads ... :thumbsup:

Share this post


Link to post
Share on other sites

Ditto on using the old bearing race as a press for the new one. I believe that was mentioned in the other thread on stem bearing replacement.....:thumbsup:

Share this post


Link to post
Share on other sites

vetplus-

Yeah, and it might have been you that mentioned using the old race also. Thanks again for all your help. Everythings holding up well.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

Sign in to follow this  

×