Swing arm bushing replacement

Wondering what is the best way to remove and replace swingarm bronze bushings. I had an old swingarm and drove them out cold but am wondering if heating the swingarm and chilling the bushes might be better to install? Perhaps cutting a groove in the old bushes with a hacksaw before removal? I figured I could draw the new ones into the arm with a piece of threaded rod with a plate on either end. Any and all opinions greatly appreciated.

If you don't have a press, threaded rod will work. Either way, you should be able to find an appropriately sized socket to use as a drift. I wouldn't bother to heat the swing arm, but chilling the new bush for installation might help. Also, if you have access to a lathe, you can reduce the OD of an old bush slightly and use it along with the spindle to help align the new bush.

NickZ said:

If you don't have a press, threaded rod will work. Either way, you should be able to find an appropriately sized socket to use as a drift. I wouldn't bother to heat the swing arm, but chilling the new bush for installation might help. Also, if you have access to a lathe, you can reduce the OD of an old bush slightly and use it along with the spindle to help align the new bush.

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All good advice so far , but in my experience the 2 buses last forever , It's the cradle tube that wears out . Several reasons : 1 : Failure to lube with very thick oil . 2 : Previous owner used grease , even once will hurt things irreparably . 3 : Plus the cradle / pin support from the word go is inadequate , a small central bolt holds it together . 2 clamping / fixing points outward each side of it are absolutely necessary , like the MK 111 model uses . Enjoy .

Kegler clamps in place. The pin has measurable wear and I see no sense in replacing one and not the other. The pin had been greased at least once by a PO so further reason to change everything. FWIW the cradle tube measures OK with just a few thou. Play between it and the pin.

I use my 6" vise and large socket to press them out and just the vise to press them in. I soak the new bushings overnight in 140 wt oil before pressing them in.

MikeG said:

Kegler clamps in place. The pin has measurable wear and I see no sense in replacing one and not the other. The pin had been greased at least once by a PO so further reason to change everything. FWIW the cradle tube measures OK with just a few thou. Play between it and the pin.

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All good . I have a small bag full of swing arm bushes , all like new . The pins were tossed into the trash , corrosion from P.O.'s using grease I would surmise . The bushes soaked up oil and held it for a long time , many years , the pin(s) not so . No corrosion at all at the bushes , but plenty on the hardened pin(s) which were starved of oil lube .

MikeG said:

Wondering what is the best way to remove and replace swingarm bronze bushings. I had an old swingarm and drove them out cold but am wondering if heating the swingarm and chilling the bushes might be better to install? Perhaps cutting a groove in the old bushes with a hacksaw before removal? I figured I could draw the new ones into the arm with a piece of threaded rod with a plate on either end. Any and all opinions greatly appreciated.

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The tolerances if the OD of the bushings and ID of the swingarm cause there to be many answers. In all cases:
1) I soak the bushings in the oil I will fill with.
2) I lightly sand the inside of the swingarm, clean thoroughly, and feel with a clean finger for burrs, bumps, scratches, etc. The tiniest burr can make it difficult.

Then I try to hand press them in. This works sometimes.
If that fails, I switch to my press. Usually, they go in easily and a vice would have worked just as well.

Sometimes, it takes a lot of pressure and that's when the PITA starts. When using a lot of pressure, they will shrink somewhat, and the pin will be too tight or not fit at all so reaming is needed so I quit that long ago and stop as soon as I see that they are too tight - press them back out and sand the outside a little and try again. Having the outside contaminated hurts nothing.

Mike, turn an aluminum mandrel on your lathe, a .010" clearance slip fit, with a shoulder to push it in.
No heat.