Replacing swingarm bearings in 1980 KTM

[sachsmx]

Does anyone out there have experience with replacing the swingarm bearings in the KTM aluminum arms? I have removed the old bearings with no problems and have the new bearings and sleeves ready to go. It looks as though the only way to do it is to preassemble the sleeves into the needle bearings and install the o-rings, then press the bearing/sleeve/o-ring into the swingarm in one shot. Is this correct?
I plane to use a little heat on the swingarm and have the bearing subassemblies in the freezer right now. I have a small press if the going gets tight
I'm just wondering if there's something I'm missing here [?]

[Lloyd Boland]

I just did a set on my 1976-7 MC-5 but I think the 1980 is a little different.  On mine, when I took the swingarm off the roller bearing just fell out individually.  The outer race of the bearing gage was frozen to the swingarm and it took quit a bit of work to remove it.  Once I got the old race off, the new bearing went in fairly easily.  The '76-7 MC-5s have an inner nut that have to be tightened first on the swingarm and held in place with a thin wrench when you install the swingarm bolt.  I am not sure if this pertains to the 1980 bikes.

[sachsmx]

I'll answer my own question as it may help others in the future. The best way (maybe the only way) to install new swingarm bearings on the 1979 to 1981 (possibly later model) KTMs is to preassemble the needle bearing, sleeve, and o-rings, lubricate them well with waterproof grease, and freeze them overnight. Heat the bearing bores in the swingarm to about 300 degrees F and the drop the bearing assemblies into the swingarm one at a time. A small press or vice is handy as is a large socket that is larger than the small end of the bearing spacer to allow the needle bearing to fully seat in the swingarm. You can press directly on the large end of the sleeve to push the needle bearing into the swingarm. Just be sure to freeze the bearing and heat the swingarm as this reduces the amount of interference by quite a bit.

[garrettccovington]

I have a 1979 mc80 and will be following this topic. Thnks for the info.

G

72 six-day
79 KTM MC80 250