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All the proof I needed was assembling my bottom end. There was NO way that crank was going through those bearings without some serious beating or a press. Having no press, and not wanting to go about banging on crank ends, I heated the case with bearings installed and froze the crank. Slid home like... (insert dirty thoughts here).

On top of that, there was NO way the old bearing was coming off the crank either until it was heated, and then it slid right off. How is that possible if the ID of the bearing got smaller when it was heated up?

Anyway, I know what works in my garage. Maybe the physics are different over there ;).


J.

I didn't ask for his permission to 'publish' his words. If he wishes I would have asked, I apologize for the oversight.

I contacted Charlie Rowlett..CBR bearings. I asked:

Greetings:


Regarding steering stem bearings: Do you recommend, or find it beneficial to do the 'freeze' routine to stem bearings? Some think that process indeed shrinks the metal, EXPANDS the ID of the bearing..others argue otherwise, that it makes the ID smaller.


I put my bottom bearing in the freezer..never had any problem seating it on the stem with the use of a correctly sized piece of pipe and a tap from a 2lb sledge using an old inner race as an interface.


Thanks!

Mr. Rowlett's response:

Thank you for your e-mail.
The bearing to stem press fit is generally very light, but I do recommend putting the stem and triple clamp in the freezer for an hour, especially if it's aluminum.
In all of our lab tests, freezing a bearing has decreased the ID and OD by up to .001".

To repeat a few words just to make everybody really happy:

In all of our lab tests, freezing a bearing has decreased the ID and OD by up to .001".

That means PivotWorks is incorrect and I stand corrected.

That's nice!

End of story...now y'all STFU!

Cheers!

worked with a lot of impressions making dentures and crown and bridge working with gold and other precious metals, and most of us learned the same principles in 7th grade science, molecules shrink with cold, expand with heat, of coarse 7th grade was a long time a go for some of us

O is a shrinked O, with the outside diameter reduced and the inside increased.

...I didn't take any coarses in 7th grade anyway........never could find enough candles to be able to see to read my books or write with my charcoal stick after I got in from followin' a mule and plow all damn daylight long....

canyncarvr wrote:Freezing makes things smaller..they contract. :

That's exactly why when skinney-dipping in a cold pond I will give a disclaimer before coming out of the water.

I have an extra inner race. I will measure it at room temp (ID and OD) and then freeze it and measure it agian. Let's get to the bottom of this.

Ok, here are my measurements. The inner bearing race was first marked so that the same location was measured both before and after. The first (warm) measurements were taken with the bearing outside in the garage with an outside air temp of 85 degrees. Then the race was placed in the freezer at 0 degrees for 2 hours and measured again (cold).

Outside -
44.34 mm - warm
44.32 mm - cold

Inside -
29.98 mm - warm
30.03 mm - cold