The seals have nothing to do with the quality of the bearing, only how well the bearing keeps out the dirt and moisture. You could try using a non-contact rubber seal. These will keep out the dirt very well and won't lose you any speed. You may notice a slight drag if you rotate these bearings by hand, but once they are assembled and your weight is on the skates you won't lose any speed. Non-contact sealed bearings are not overly expensive, so it won't cost you a fortune to trial them.

The most significant increase in speed will be obtained by using a quality oil lubricant. We have tested a bearing with non contact seals and a Teflon Oil Lubricant. These bearings have been used in Inline Hockey (Roller Hockey) with some very good results. Rather than marketing these bearings ready oiled we would rather just let you know the oil that we tested (Slick 50 One Lube). Try it. We make no claims other than we feel that this lubricant has proved very effective in our test bearings. If you decide to trial this oil in your own skf bearings we are very eager to learn of your experience. Please e-mail us. If you can suggest alternative or better lubricants we would be happy to publish your suggestions here.

Internal axial and radial clearance (how much movement there is in both directions when the rings of the bearing are pushed in opposite directions). Too little and too much clearance can both be detrimental to bearing performance. You can usually feel this movement with your fingers but you will not be able to determine whether it is within acceptable limits just by feel. Check the manufacturers specifications on the bearings and try to stay within the "MC3" range for normal skating applications. (The terminology "MC3" will be recognised by most bearing shops). If you want more speed, you will want to loosen up the internal clearance to allow the timken bearings to spin more freely. We have had some very good success supplying "MC5" clearance with a very light oil lubricant for speed skating. These are not available in a serviceable shield type though. 

Manufacturing quality control and cleanliness. 

The best way to ensure that you get a good bearing is to stick to the well known manufacturers, and by this we do not necessarily mean "well known skating brand names". If you are buying pre-packaged sets always check on the actual bearing to find out the manufacturers name and country of manufacture.

I have been in the bearing industry since 1984, and the biggest problem with the industry is that too many bearing sales people don't know enough about the product that they are selling. I have come across people with over 20 years experience in the industry who still get scared when a customer starts to ask about load ratings, limiting speed, internal clearance and yes, you guessed it, [ABEC 9 bearings] precision. What has happened here is that someone has been told a basic fact that higher precision allows for higher speed (and this is true under certain conditions). Not fully understanding this, the information has spread and gained momentum (mainly through the Internet). There are many more inexperienced people in the bearing industry than there are experienced people and this has allowed for rapid growth of this falsehood.

We have heard that somebody is producing a 608 bearing with ceramic balls for skating applications. Ceramic Balls are relatively new technology, so we can not answer this question at this time. We suggest that if the bearings are not over priced, give them a try. We would look forward to your comments you have tried them.

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PRB-04

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