How hot is too hot for your bearings, cases, and seals?

Dirt Bike Technical discussion. This is for a little more in depth discussions :-)
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Sandblaster
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How hot is too hot for your bearings, cases, and seals?

Post by Sandblaster »

How hot is too hot for your bearings, cases, and seals?
We are experimenting and should have some results fairly soon... :shock:
If bikes are for kids I'll never grow up.
81cr450
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Re: How hot is too hot for your bearings, cases, and seals?

Post by 81cr450 »

I have an aluminum hardness tester at work if it helps any, also have a sacrificial case set. I don't think you could get bearings hot enough to ...
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Sandblaster
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Re: How hot is too hot for your bearings, cases, and seals?

Post by Sandblaster »

Ah.... fantastic.
I can even send you some cases if necessary...
I've head but never had it proved that at 400F aluminum starts having issues...
It would be cool to prove it...
And heating bearings as a whole would take a lot of heat to ruin a bearing..... However...... Using the Motorrad method could damage a bearing if you over heat. I found a new KX500 bearing and will ruin it next week and show my results :lol:
If bikes are for kids I'll never grow up.
81cr450
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Joined: Sun Jan 13, 2013 6:08 am

Re: How hot is too hot for your bearings, cases, and seals?

Post by 81cr450 »

I'm thinking, heat a case half in the oven to 300 test, 350 test , 400 test. I'm betting its done there but if Im wrong, could keep going. The tester is aerospace quality, we use it to test for junk d-max heads. This is awesomeness , most screwed up parts are from the "mechanic" , nice to learn the actual failure point. Got a junk AF frame , I'd like to learn more about frame anealing too
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Sandblaster
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Re: How hot is too hot for your bearings, cases, and seals?

Post by Sandblaster »

Here is some results for welding on Aluminum frames:
These results were based on the Brinell scale.
Here is the test piece from a 01 CR250:
test piece 1.JPG
test piece 1.JPG (71.22 KiB) Viewed 9076 times
01 CR250 square tube stock is 74
The edge of the weld is 70
The weld is 70.

Here's some comparison specs
86 CR500 swing arm 82
87 KX500 swing arm 78
97 KX500 swing arm 72 seemed odd but got the same # in multiple spots
2003 CR250 swing arm 83 , the frame is 80-83.
If bikes are for kids I'll never grow up.
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Sandblaster
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Re: How hot is too hot for your bearings, cases, and seals?

Post by Sandblaster »

The person who did the testing said that he see's failures at about 60 on the Brinell scale.
If bikes are for kids I'll never grow up.
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