Crankshaft bearings

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madsundaysurvivor
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Crankshaft bearings

Post by madsundaysurvivor » Sun Jun 07, 2020 7:50 pm

Hello,
A simple question about b44 cranckshat baearings. Parts manual says right Hoffmann R325 balls anf left hoffmann r325l rollers.
In my engine are the same part number plus "v3"
I can't find the meaning of the hoffmann codes and I don't know if the OEM bearings are standard clearance or c3

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Re: Crankshaft bearings

Post by homebrew123 » Mon Jun 08, 2020 9:20 pm

Hi, you should always use C3 bearings in any application where the bearing is an interference fit in the casing, and if you warm the casing in the oven at 200-250 which will be maximum for about 5-10 mins until water sizzles on it, and place your bearings in the freezer for a couple of hours first. If you line the bearing up perfectly under those circumstances it will drop straight into the hole, no messing, and then just leave it to cool on the kitchen table as I do lol.
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Re: Crankshaft bearings

Post by kommando » Tue Jun 09, 2020 7:36 am

V3 is a vibration spec, nothing to do with internal clearances, at the time Hoffman used dots or etched circles to denote internal clearances. C3 is the default internal clearance for a bearing set in alloy and Hoffman developed the concept using 3 circles or dots.
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Re: Crankshaft bearings

Post by madsundaysurvivor » Tue Jun 09, 2020 7:09 pm

Thank you for your answers.
I usually fit c3 bearing, less in some two stroke racing engines, then use c4 with poliamide cage.
But in case always learn something, I will look for the three marks on the bearing

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Re: Crankshaft bearings

Post by robtg » Wed Jun 10, 2020 7:47 pm


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