replacing bitex RAR9 freehub bearings

[JoO]

Grease and seals, fill rate.

I see some people using the ceramicspeed grease to improve performance.

I read that some greases "liquify" with the temperature increase that comes from the bearings spinning. I don't know if that effect can be observed in cycling but sounds cool.

You don't want it to pour out of the bearing but you want it nice and thin.

Anyway, skf/ntn with low contact seals and replace the grease with a low fill rate of something good and you should be very competitive.

Remember that the seal is the only thing keeping those bearings alive, so use low contact rather than no contact. A bearing that loses it's friction advantage after 50km and spins twice as gritty after 200km is completely useless.

About the extraction i'd try applying some heat to the freehub body, and/or try to devise a press from a threaded rod to press the bearing put.

If you use the socket method I said you dont really need to fear the bearings coming out crooked as it's using two contact points. Apply some heat and you'll have both bearings out in under 20 seconds. No need to fiddle around with pullers.

I received a dozen Enduro 6802 + 4 TPI 6802 when I bought the bitex hubs at a sale.
The TPI are a lot smoother than the Enduro's. Even when I took the seals of the Enduro's.
NSK VV are smoother than the TPi's.

I have bought ceramic speed general and TT grease.
I will replace the grease in an enduro bearing just to please my curiosity.

Right now I am running SKF bearings with trimmed seals (misordered with standard 2RS seals). Will see how log these last.

An update regarding the change of grease. Ceramic speed allround grease made the bearing a bit smoother. With ceramic speed tt grease the enduro bearing feels as smooth as nsk vv in the hands. It only last 1000 k so they need some regular care

[JoO]

Changing the bearings with wheels mf tool was easy.
Changed the bearings to enduro’s with ceramic speed TT grease 30 percent fill rate.
The freehub spins in my hands.
This will be my race/special event freehub.

[alcatraz]

Good idea. If you try to use it for training or long event you'll find the bearings get gritty really fast. The seals aren't keeping the lube in or contaminants out properly.