Topic: which wheel bearing is this?

[evinrude7]

a 6304Z or a 6305Z

[Bodi]

Kinda hard to read the bearing numbers in that pic. If it's a K6 rear wheel the brake side hub bearing will be a 6304 but use a 63042RS not a 6304Z.

[754]

Punch in bearing online, will give a descrip. . The differe central may be sealed vs shielded.
 Sealed is better by that area if brake drum.

[evinrude7]

Kinda hard to read the bearing numbers in that pic. If it's a K6 rear wheel the brake side hub bearing will be a 6304 but use a 63042RS not a 6304Z.

why the rs and not the z?

[Bodi]

2004-Z has a shield on one side, although double shielded bearings are usually marked as Z but ordered as ZZ. The shield keeps gravel out but lets in fine sand and water, and the grease can run out freely if it gets hot. 2004-2RS has a contact seal on both sides: grease stays in and dirt/water stays out.
The contact seal has slight friction but I believe that's trivial and the benefits are worthwhile.

[evinrude7]

2004-Z has a shield on one side, although double shielded bearings are usually marked as Z but ordered as ZZ. The shield keeps gravel out but lets in fine sand and water, and the grease can run out freely if it gets hot. 2004-2RS has a contact seal on both sides: grease stays in and dirt/water stays out.
The contact seal has slight friction but I believe that's trivial and the benefits are worthwhile.

thanks bodi

[evinrude7]

Punch in bearing online, will give a descrip. . The differe central may be sealed vs shielded.
 Sealed is better by that area if brake drum.

thanks 754

[pjlogue]

Kinda hard to read the bearing numbers in that pic. If it's a K6 rear wheel the brake side hub bearing will be a 6304 but use a 63042RS not a 6304Z.

why the rs and not the z?

The "RS" designation I believe stands for rubber seal.  Much better to use an RS bearing anyplace that dirt or moisture can get at the bearing. 

-P.