OK, after I posted this morning I decided to call the bearing experts
that I talk to periodically, at www.bocabearings.com
.Yes the 688 are the smallest and 698's are larger. Apparently the
names attached to the numbered sizes are assigned depending on which
way the wind is blowing. Micro-- Mini-- are both listed with either
688 or 698, depending on the manufacturer. In one place I read that
they are all referred to as Micro bearings. This is really confusing
and I feel sorry for someone that is trying to mail order bearings for
the skates using the name.
While I was on the phone, I asked the tech guy at Boca about these
smaller bearings. He told me that the main advantage , all other
things being equal, is that the smaller bearings have the capability
of spinning faster. Now why this is important , when comparing to a
608 that is designed for 10,000 rpm plus, I don't quite understand. I
think I figured out years ago that to run a 608 on the average Inline
Skate wheel, at it's designed speed range, you would be skating at
200-400 MPH... That fast, I'm not interested in :)
He also told me that the smaller bearings should wear as well as the
608's. I questioned him about "side loading" and the smaller bearings
tolerance for that. He told me that side loading on Inline Skates is
minimal and that these smaller bearings should hold up as well as the
Now, as far as the bearings that I got with my K2 Catalyst, which are
marked K2 and nothing else( No ABEC Rating at all ) , they are total
garbage. They don't roll well, are noisey and 'draggy" , and as posted
before, I removed them from my Catalyst skates. K2 probably has many
owners of skates with these bearings, thinking that the skates are NG,
or the wheels, when in fact it is the bearings that suck!
The Ninja Mini-misers ( ABEC 5 ) , which I wasn't crazy about in the
beginning, and have since moved from my retired Core Carbons to the
Catalysts, have proven to be very fast and seem to work well. This is
since I cleaned them of the lubricant that they were initially lubed
with which was great at attracting dirt, and re greased them with
Sonic Gel. They don't make noise anymore, seem to stay clean, and are
FAST!! I am going to try and use them at least until the wheels that
they fit, wear out. If they don't require excessive cleaning and stay
fast, I may replace the wheels and see just how long they last.
The tech person at Bocabearing also mentioned the "Sealed "
Maintenance free bearings that they sell. These are not shielded, but
sealed.. He said that no bearing will last forever and remain clean
forever, but apparently these sealed bearings can go for years without
cleaning and lubing. At that point you can buy a "kit" from Boca
Bearings and rejuvenate them back to original condition.
>I'm looking at the box that my RB E9 Carbons came in and it clearly says Micro
>bearings. They also have a sticker on the frame that says Micro bearings. When I
>look at the Ninja bearings under magnification they clearly say 688.
>I agree with Bill and Daryl.
>Micro = 688 (smallest)
>Mini or Dwarf = 698
>I know the K2 Catalyst uses 698 Mini or Dwarf bearings, although I believe K2
>refers to them on their site as micro bearing technology. K2's marketing is
>likely the source of the confusion.
>> Well I guess the confusion comes with the naming of the bearings. The
>> Core Carbon skates come with Ninja Mini Bearings which are the
>> smallest I have seen. My K2 Catalyst came with MBT Micro Bearings
>> which are large than the Minis. Neither one of these bearings are
>> numbered, and that is why I wasn't sure of the numbering system.
>> Apparently they are named with no reference to their number?? Really
>> confusing. Anyway, I think 608s rule.