Hey guy yesterday during racing I lost the rear bearing on my vir-tus 7port. Less than 4 gallons in. Anybody else seen this. Just seems odd to me!

well.. I just want to ask.. were you running Nitrolux fuel?

Byrons 25/8

I have not used 25/8 but have used 25/9. 25/9 eats engines for me. I stopped using it and only use 25/11. I advice to use 1-2% of Byron lubebooster ( castor oil )

IMG_1547.JPG
Found it.

The worlds blend is great for bearings however rust is not

Come on guys!! Rear bearing would be OK to make 4 gallons on any fuel blend !!
My thinking goes to lean High speed needle or accidentally dirt intrusion on bearing.

I always try and keep a slightly rich tune. If I go lean it's almost always the bottom. But that's rare. I feel comfortable about tune and fuel. I'm just wondering if anybody else is having trouble with this bearing? At 132.00$ a bearing I don't know that I want to order one, or just replace the whole motor

Here is how many revs the bearing have done, if you take an avarage of 8 minutes a tank over 4 gallons (16 liter) and set an avarage rpm of 20.000rpm.

8 tanks a liter X 16 liter X 8 minutes a tank. Thats 1024 minutes of running.

1024x20000=20.480.000 revolutions not bad, is it?

Considering I have an OS and a tko ceramic in it with 9 gallons on it and it still runs with little work. I would say it pretty much sucks!

Novarossi Direct has them for $89. I forget offhand, but TKO or one of the other bearing companies might make a 14,5x26x6x5,7x4,7mm bearing also for even cheaper.

These special made bearings are only sold by Novarossi with a very special price.

When it comes to Byron 25/9 vs 25/11, the bearings has a lot shorter lifespan with 9 than with 11 percentages oil. A mix of both is the perfect blend

So beyond fuel another thing I know kills bearings is aggressive triggering under no load...Rapid spikes in the engine RPM will cause the balls to skid instead of roll, and once the balls start skidding they start creating flat spots on the balls and or channels in the outer race, once it happens once it can happen easier the second time and easier the third time.....Bearings are especially vulnerable when the engine is cold....obviously combine this abuse with a low grade lubricant and the issue is compounded.. I have worked with several drivers who have a nervous trigger finger and they are always hurting bearings..either out of nerves or anger rapid hits of throttle while the tires are off the ground is a very bad thing for these engines...

TKO's site says they have the special bearings for the Novas. I think about $40 or so a piece.