Midlife's 150 Swingarm Bushings
 

My buddy was kind enough to turn some UHMW (that he donated) into swingarm bushings for Midlife. These bushings are located in the swingarm (vs. the frame), and the stop point inside the tube makes bushing extraction a real pain. The OEM bushings consisted of an inner steel tube surrounded by an elastomeric material with an outer steel tube. The inner tubes had completely separated from the rubber, and not much rubber was left. The remaining outer tubes were very stubborn.

This is one of the tubes after much wrestling.

http://i158.photobucket.com/albums/t...d/DSC06340.jpg

You can see the shoulder that the bushing butts up against.

http://i158.photobucket.com/albums/t...d/DSC06342.jpg

There was a spot where the weld from the swingarm assembly penetrated a little too far into the tube. After this shot, a little work with the die grinder and a flap wheel took care of it.

http://i158.photobucket.com/albums/t...d/DSC06350.jpg

This is the UHMW material that we used. I just cut a couple of pieces off to be chucked into the lathe.

http://i158.photobucket.com/albums/t...d/DSC06343.jpg

This is the lathe that my buddy just picked up. It differs from mine in a couple of ways, most notably that it has a milling attachment. I covet it.

http://i158.photobucket.com/albums/t...d/DSC06345.jpg

This is the UHMW after a quick face cut.

http://i158.photobucket.com/albums/t...d/DSC06344.jpg

And the turning begins. Since this was my first time witnessing this process, my buddy did it in several steps for me.

http://i158.photobucket.com/albums/t...d/DSC06346.jpg

This is after all of the bulk was removed.

http://i158.photobucket.com/albums/t...d/DSC06347.jpg

It measured perfectly. I love this machine!

http://i158.photobucket.com/albums/t...d/DSC06351.jpg

My buddy then chucked a center drill into the tail stock.

http://i158.photobucket.com/albums/t...d/DSC06353.jpg

http://i158.photobucket.com/albums/t...d/DSC06354.jpg

This is the perfect starting hole that results from the center drill.

http://i158.photobucket.com/albums/t...d/DSC06355.jpg

He then chucked a 1/4" bit into the tail stock...

http://i158.photobucket.com/albums/t...d/DSC06356.jpg

...followed by a 1/2" bit.

http://i158.photobucket.com/albums/t...d/DSC06357.jpg

My buddy then flipped the piece around in the chuck, quickly chopped the end off with a hacksaw, and then trimmed it to perfection. The final product.

http://i158.photobucket.com/albums/t...d/DSC06358.jpg

The final hole size is actually too small, but we didn't have the required 14mm drill bit. I'll look for one tomorrow; if I don't find one, I'll use a 9/16".

I'm anxious to see how this new bushing performs. At the very least, it will be much easier to pound out when the time comes.

that looks awesome guys .....Mrs. midlife will love the fact that her chain will stay on wile she is powering through mud or up a steep hill (these are the two area's that the chain always came off when she needed it to stay on)

Yeah, I don't expect much side play with the new bushings.

there is no emocon on here to express her happiness

I'd be happy with a beer emoticon.

Lol! Now your speaking my langauge! :lol:

I couldn't find a 14mm drill bit, so I bought the 9/16", which is 0.3mm larger. I placed a bushing in a v-block and chucked it in the vise.

http://i158.photobucket.com/albums/t...d/DSC06359.jpg

Much like the Native philosophy of building a canoe, you just trim away everything that is not a bushing.

http://i158.photobucket.com/albums/t...d/DSC06362.jpg

They fit nicely on the bolt.

http://i158.photobucket.com/albums/t...d/DSC06361.jpg

I then drilled and tapped a hole in the swingarm for a zerk.

http://i158.photobucket.com/albums/t...d/DSC06363.jpg

http://i158.photobucket.com/albums/t...d/DSC06365.jpg

A little grease and a little hydraulic pressure, and they slid right in.

http://i158.photobucket.com/albums/t...d/DSC06367.jpg

Here ya go, Midlife.

http://i158.photobucket.com/albums/t...d/DSC06368.jpg

http://i158.photobucket.com/albums/t...d/DSC06369.jpg

I'm gonna pick up some washers and jam nuts for the bolt (hopefully tomorrow), and it'll be ready for installation.

the wife said ....and I quote "COOL now I won't loose my chain" un-quote

Nice machine work! Those bushings will serve you well I'm sure :). Wonder why the chinese use such weak ones in the first place?

Cost. It costs them very little to create an elastomeric with Heaven-knows-what as the elastomer and very thin wall tube. Nobody expects these machines to last, so why would they put quality parts in them? That's where we come in. We're China Riders. :D

Very nice, hope they hold up. Let us know how they do.

I used to work in a fab/machine shop and that stuff is awsome.