Swingarm bearings


I suppose you are talking about the outer race that's in the swingarm itself.
Without an extensive selection of bearing pullers, the best way is to use a small grinder (like a Dremel tool) to cut and then collapse the race. For these jobs I prefer the grinding disk over a stone simply because the cut is thinner and therefore goes faster. None of these "cutters" is going to get down in the corners, so you'll need to end the job with a chisel and hammer.
Bring your lunch and wear your eye protection. This is not a fast job.
Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.

Richard sums it up pretty well. The races BMW presses in have very little lip under them to get a number of "race pullers" to get ahold of to pull them out. The BMW tool is expensive and works well. I am not sure if Cycle works sells a tool for the swing arm races, I know they sell one for the equally hard to pull steering head bearings. If they don't and you can't find a puller to fit, cutting the races out is the only option I can see that will work. Good luck. St.
Beware! I do not suffer fools gladly! St.

Sounds like maybe more work than I need to get into. The bearings feel pretty good as they are so now I'm thinking I should just leave them be.
I was thinking maybe taking a torch to the outside to try to expand the steel to let the bearing out but if you're not suggesting that I won't get into it. I don't have any bearing removal tools so that's out too.

Hey Mike,
Give it a go, you already got the swingarm out. I will also agree with the above posters with one modification. That is, you can get a cheap 'blind bearing' removal kit from Amazon. I do the grinding of the race as much as possible and THEN use the blind bearing tool and things work well. My first few did take me a handful of hours. Then I just got confident enough to grind to the right depth. I would guess 20 minutes with the dremel and 20 minutes working it out. Keep in mind you got three more sets of bearings on this bike (Steerer and the two wheels). Wheels are super easy if you just heat the aluminum rim with a heat gun to expand. Then using the blind bearing tool they pop out super easy. One helpful hint, when installing the new ones, put the race in the freezer for 20 minuties and lightly lube.
Cheers,
Ethan

Thanks Ethan, I did already know the bearing in the freezer trick but thanks for the reminder.

• Unless you see pitting in or on the race bearing surface then there is no need to replace the race. You can simply run the new bearing in the old outer race. The bearings and races are made to extremely close tolerances and everything will work out fine.
• Lubrication of those bearings should be done AT LEAST once a year. Continual introduction of new grease is not about "lubrication" as much as it is about pushing out water and dirt before they can do damage.
• Lubrication of either swing arm bearings requires a "needle nozzle" grease gun fitting like this one Right Here ! If you own a metal lathe, then making your own is a great 20 minute project.
• The heating/cooling "trick" will not work to remove the race simply because the swing arm has the greater mass and the race will therefore (thermally speaking) do what the swing arm is doing. In order to get a drop-in or drop-out situation, the temperature difference between the 2 parts would need to be on the order of 150°F. The tight confines and the very high percentage of contact surface won't allow that.
Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.

Hi Richard, I agree not ever event calls for race replacement. Just one point to share, the Steerer and the Swingarm bearings are more prone to failure by brinnelling (sp) which is when the bearings slam into the race in the same spot over and over. It is indicated by lines on the race. To the user, you would feel notchy steering in the handlebars and lack of smooth travel in the seat (bouncing on it). Pitting is often a symptom of moisture often due to lack of use.
Best of luck to you Mike!

The bearings on my swingarm are sealed units. I'll still clean them up and whack some grease to them. They both feel pretty good as of now. The new paint looks good.

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