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Discussion Starter #1
So, I did my rear brake today, but it was a pain to get off the ABS ring. My old disk was fairly crusty, so much so I did not notice the center part is cast aluminum like material. I hadn’t really looked at the new one at that point. I figured out to heat the screws to loosen the thread lock, but wasn’t sure the trick in getting off the ring, so I looked at some posts and a couple of videos online. Everything I read and saw showed heat as the answer to help remove the ring. So I tried that only to find is made no difference. As I was worried about damage to the ring I did not want to force it (my bike is my daily driver and did not want it to be down). Upon further inspection I figured out the center is some kind of aluminum. This is an issue as it would be wrong to heat the hub to remove the ring. These 2 materials (aluminum and steel) expand at very different rates. The aluminum will expand around twice as much as the steel (or cast iron). This will make the press of the fit between the 2 even more tight as the aluminum part is on the inside. The wheel hub, transmission bearings and such are aluminum on the outside, so yeah heating those is good practice. Once I figured out the inside was aluminum I put the disk assembly on the wheel lying to the side (removed the shim as it would act like an insulator). Using the wheel as a large heat sink I was able to cool center of the disk assembly while the ring was still a bit hot due steel being a bit more resistant to thermal change in that time relative to aluminum. At that point it was a bit easier to pop the ring off. Possibly all the previous attempts helped, but it came off at that point, so who knows. Figured I would mention it, if I am off base, or missed something please let me know.

Tl;dr don’t heat your rear ABS ring thinking it will help you remove it. (tl;dr = too long didn't read)
 

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Wrencher Extraordinaire
2005 K1200LT
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I just hit light heat on the ring from the outside edge without soaking the entire hub. It just popped right off.
 

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Discussion Starter #3
I just hit light heat on the ring from the outside edge without soaking the entire hub. It just popped right off.
I am sure you are some kind of an artist with a heat gun, but I am just saying it is very difficult to heat up a steel ring enough to move it without heating up the aluminum hub that it is pressed on. If the aluminum that is pressed into the ring heats up half as much as the ring the net difference is the same.
 

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I am sure you are some kind of an artist with a heat gun, but I am just saying it is very difficult to heat up a steel ring enough to move it without heating up the aluminum hub that it is pressed on. If the aluminum that is pressed into the ring heats up half as much as the ring the net difference is the same.
Such a crude tool, heat guns. This requires the pencil flame of a torch :)
 

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I got a mini soder / torch from Radio Shack in the 1980's . works great getting heat to small places . I used it on my rear brake rotor..

I use it to do a lot of stuff..clean the spark plug in a 2 stroke roto-tiller, ..++
 

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Well. I drilled my screw heads off for the ring Because i installed a new EBC rear rotor and they provided new screws. But. I used map gas. Heated the ring even, but not to hot. Used a small claw prybar. It popped right off.
 

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Wrencher Extraordinaire
2005 K1200LT
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14,191 Posts
I am sure you are some kind of an artist with a heat gun, but I am just saying it is very difficult to heat up a steel ring enough to move it without heating up the aluminum hub that it is pressed on. If the aluminum that is pressed into the ring heats up half as much as the ring the net difference is the same.
Yeah you are thinking like a machinist here, the ring is not a press fit (if it was there would be no need for the screws) but the dissimilar metals do form a bit of corrosion between the two, a small amount of heat is all that is needed to break that corrosion bond.
 

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Well. I drilled my screw heads off for the ring Because i installed a new EBC rear rotor and they provided new screws. But. I used map gas. Heated the ring even, but not to hot. Used a small claw prybar. It popped right off.
I did the exact same thing last summer following Kirk's video. Worked flawlessly.
 
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