bearings with oil seals

Surfrjag

Member
Mar 18, 2010
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chesapeake, va
i took my main crank bearings and a front wheel bearing to a local bearing shop and got replacements. they came with oil seals on both sides of the bearing and came prepacked with grease. anyway i was wondering if either one would cause a problem if i left them on. :-/
 
For wheel bearings, fully sealed is a good way to go and probably the best choice.

Hard to believe they sold you sealed bearings for the engine though. My first thought was that you should be able to remove the seals and clean out the grease, allowing them to be lubed by the fuel-oil mix as usual. On second thought though, I would wonder about the suitability of the bearing they sold you to be used by this application. A general industrial bearing (which is what it sounds like they sold you) might not have the tolerances, finish, and speed rating of correct crank bearings. After all, crank bearings need to spin up to 10,000 rpm. I'm not sure the bearings they sold you are up to that demand. I personally wouldn't take the chance. Buy some correct bearings from rockymountainatvmc.com or ebay (get name brand), or just buy some factory Yamaha from your dealership. A lower end is a terrible thing to waste....
 
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good advice royal, dont chance it, but if you do, remove the seals, and as for "prepacked bearings" pick the seal and look, most dont even have enuf grease in them to properly "run one off" pack them yourself with as much red or blue waterproof grease as you can get in there
 
bearings have different ratings..... when i built my kart motor (13hp honda gx390 4 stroke) i got bearings from a local place. but i made sure they were the same bearings that came out from the factory. i paid close to $50 for a pair of bearings, and they had other bearings there that wear only $10 for the pair. like said above, a bottom end is a terrible thing to waste for some pourly made chinese bearings. plus alot of bearings are made to run grease or oil in them, so might not take to well to fuel being run in them either.
 
thanks, i took some hotrod bearings from another motor that can wait for more to come in the mail... hopefully ill have this one together for busco this weekend!!!