Site member meegusmaster shared on facebook a replacement needle bearing for the FL350 AB gear. She states that this a an upgrade over the oem part and has not had any gear box failures since installation. She has the rotax 670 engines in her machines so this is an upgrade to consider for high HP Engine upgrades.

Polaris part number: 3514591

https://www.partzilla.com/product/polaris/3514591

-Curtis

Thanks for the info.

Wow this is helpful. Now, the AB gear also gets chewed up, right?, are there any known replacements for the gear itself?

I have personally never experienced this failure but it is my guess that the input shaft and AB gear would be damaged when the bearing fails. There are no replacements for those parts that I am aware of. Best to get ahead of it with the bearing upgrade. To have a new gear and input shaft made, it would be cheaper to buy a good working gear box complete.

-Curtis

I have had an AB bearing failure. Luckily I caught it early and the damage was minimal, however, the gear and shaft are currently unusable.
I am hoping I can find somewhere that can repair the surface. Unfortunately, most companies that offer hard chrome plating only seem to do business with other industries.

I've had an A/B failure as well.
I tried a lot of things but nothing worked for me and had to buy parts from Derek Tisinger.
Great guy to deal with.

One of the most deadly things an oddy owner can do is a "driveway tune up".
The transmission is a splash lube system and the A/B gets NO OIL when it's just sitting there and the owner is revin the piz out of the machine to "tune" the carb.
Also after it's been sitting for a long time (like over the winter) I pull the belt, put it in gear, turn the rear wheel by hand. This will pull up some oil and in turn oil the bearings.
I also over fill my gearboxes. I don't use the factory fill line. I put in about 1 3/4 quarts of oil in the transmission. Done this on all three of my machines with no issues.
Make sure to check the Engine counter balancer oil too.
If you lost a seal it will suck the oil out and burn it in the combustion chamber and you won't know about it until it's to late.
CO