Whatever you do, If you think it has a whining type bearing noise do not keep running it as you will only further damage the rest of the engine
Have someone inspect the engine if your not confident yourself, Replace the bearing if need be
If you did have to replace it have a good look at it for rusting and be honest with yourself about weather or not your after run technique (if you do so) could be letting your bearings fail early
Also have a good look at the crank portion that is exposed to the air/fuel charge from your carb (when the crank's intake port is not lined up) and see if it is scored from fine dirt or dust ingestion, You may also want to inspect your front bearing for dirt
Another thing to look into will be your fuel, see if anyone using the same batch has had problems etc
Just because the engine has oil in it when you stop it after idling does not necessarily mean that the lubrication package is looking after your bearing in high rpm / Load and or heat situations
And if you cant find any other obvious issues it may be fair to say you got a not so good bearing from Novarossi... it can happen and does with all engine brands at times but firstly have some one look at the engine who knows a little about it before you want to blame Novarossi for a bad bearing (not that im saying that you are doing so or don't know what your looking at)
I have often seen people wanting to blame Novarossi for a "bad bearing" when in fact upon pulling the engine down the engine has digested that much dirt its not funny, Or when the bearing shows obvious sings of rust!!
Or when the engine had been ran with a fuel that no one knows anything about...
1.6 Gal or six liters of fuel does not seem like allot of engine usage but if there is something upsetting a bearing that is doing close to 40.000 Rpm then it is huge
When you buy a high quality engine in particular like Novarossi i think its fair to say that the new factory installed bearing has absolutely nothing wrong with it and it is then only running conditions or maintenance issues which cause it to fail.. at least 99% of the time anyway
Also, & particularly in Offroad racing we have a huge amount of variables on the track as far as engine loads and temps are concerned without even considering after run issues, So if one engine bearing lasts say 10-15 liters and another lasts 30-40 liters then we cant say that has anything to do with bearing quality from the factory.. specially with the load and rpm these things do
I don't mean to rant on but i have had one to many people lately want to complain about a "Bad Novarossi bearing" when the user in some cases DOES NOT EVEN RUN THEIR ENGINE OUT OF FUEL at the end of a race day!!
I think i MAY have had one genuine case for a premature bearing failure which is questionable in the past year / 100 odd Novarossi engines sold, That bearing is recent and yet to be inspected
Bottom line is if Novarossi are fitting bad bearings to engines we wont see a post in here once or twice a year questioning such, Instead we will start getting five a week...
Dave,
FUSION X ENGINES AUATRALIA