Nose wheel Tapered Vs Ball bearings

[rv9av8tr]

*** VIDEO UPDATED 1/27/12 ***
It now shows landings at 3 different airports
****************

Van's RV nose wheel is standard with tapered roller bearings, which result in significant tire resistance to roll. I had Anti-Splat-Aero change my RV-9A to frictionless sealed ball bearings. The first thing I noticed is how much easier the plane is to pull around on the ground and to steer.

But the difference in nose strut bucking behavior on touchdown is dramatically shown in this video comparison of before and after. I have also added the Anti-Splat-Aero "Nose Job" brace, however the bearing change out is responsible for the difference seen here! In a word... WOW.

http://youtu.be/W0kHXOIop5Y

[rvator51]

What kind of sealed ball bearings did you use and where did they get them?

[N208ET]

I won't be able to test it for another week or so but I am looking forward to the results.

Randy
8A

[rv9av8tr]

Good question for Allan at ASA. Last night was first flight since the change and of course it rained just before takeoff. It was pointed out the wet runway reduces surface drag..... granted it does. I'll film it again after work today, it should be dry, and see it there is any difference.

[mcattell]

Great news Mike on the change to ball bearings. Allan changed mine as well and I'll be installing the wheel tonight and testing tomorrow. I'll also post my video as I've already did the before video for comparison.

[Bavafa]

I say, dramatic difference. one that I still can't believe. Very nice.

I like to get a set of these bearings. Can they be ordered as I don't see it on their web site?

[rv9av8tr]

Your point is well taken, however wheel weight is low and its not like these see tens of thousands of miles of use. I think the immediate strut stability that results far outweighs any long term unknown that is easily monitored.

[Beancounter]

Mike that is a noticable improvement. How many revolutions were you able to get spinning the nose wheel by hand before and after. I was able to greatly reduce the nose wheel friction with the stock bearings by adding a section of tubing between the bearings. The tubing acts like a spacer that seperates bearing preload from axle torque. If memory serves I was getting 1.25 revs before and 8 after this mod.

[dougmattson]

What size and material did you make your spacer?

[Richard@Langair]

It really has nothing to do with being a roller or taper bearing. It is all about the type of seal used.

Roller bearings typically have a very light pressure on the seal unlike the way the nose wheel is setup with a bunch of pressure on the rubber seal.

I have relieved the seal surface on a couple of friend's front wheel so that the roller bearing rubber seal just barely touches similar to how the ball bearing is set up.

Once that rubber seal interference is alleviated, it rolls very easy.

I don't know that the ball bearing is ever going to fail with the kind of service use the front tire sees, but I like roller bearings myself. If they do fail, they typically do not lock up.