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Nose wheel stiff.

Question, Its all new to me,,, I just purchased a RV-7A, I find the nose gear stiff to move with hand held tow bar, back and forth,, can you let me know if its normally that stiff ?,should go left and right with ease? does it require grease,?
is there any adjustments that can or should be made? appreciate comments, Thanks David
 
The big nut should be adjusted so it takes 20lb force to turn the wheel sideways. Unlike some certified planes, the RVs are meant to be stiff this way, to prevent wheel wobble (shimmy) while taxiing & rolling down the runway.

Yes, the bushings should be lubed, but not excessively.
 
Ralph, that confirms your answer to my question, I would say it is in the 20lbs. range, thanks, David

The plans spec recommends 26 lbs when pulling laterally at the axle nut.

If you are feeling ~20 lbs on the end of a tow bar the actual value could be way higher than what is recommended. The tow bar is a much longer arm (for leverage) than the nose fork is.
 
Hi Scott,, how does one calculate the 26lbs off the axle nut, directional braking to turn nose wheel seems good, its turning the nose wheel with the tow bar that seems tight!! I do understand the stiffness as for to avoid shimmy,
I will look into the builders manual this evening,, does it specify the procedure?
David
 
Right Scott, what you said, what I meant (kind of), but now what I said.
It's good to have you on the forum to keep us straight!!
 
Grease

Keep lube off of the bellvue sp washers, the ones that look bent/ cupped, not flat. Dry makes the anti shimmy work better
 
And from time to time, grease via the grease nipple at the front of the fork!

As a "buyer" you are now the owner of the plane. Do something good, buy the plans/manual from Vans, even if the plane build is finished! THIS is the only source to look how things should be built/done and how Vans have them designed.
 
This is the excerpt from the RV-7 plans for checking breakout force.
 

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Keep lube off of the bellvue sp washers, the ones that look bent/ cupped, not flat. Dry makes the anti shimmy work better

This has been discussed at length elsewhere, and most do have lube even if one tries not to (it oozes from the lower bronze bushing). I do not have shimmy and mine have been lubricated for 1700+ hours.
 
Like Alex posted, it is impossible to keep all grease off of the belville washers.
Particularly if you use the grease zerk on the fork to grease the bushings.

I set the proper break-out with grease. Then it is less likely to change.

Excessive friction in the fork is usually because of lack of lubrication. I have seen nose gear legs that have developed rust on the highly loaded portions of the leg stub (top fork bushing aft side and bottom fork bushing, fwd side) because of no grease.
Using the grease zerk doesn't always reliably get grease on all the surfaces. Especially if it is pumped in while the nose fork is loaded from the nose wheel being on the ground.

Because of this, we remove the fork from the leg during each 100 hr inspection (yes, we have to do 100 hr inspections because our demo aircraft are not certified in the E-AB category).
We clean, inspect, and re-grease with waterproof grease (the blue boat trailer stuff you can buy at the auto parts store) We have found this to hold up better than other types we have used, though there is probably many others that give just as good of performance.

If you do chose to grease with the zerk and not fully disassemble, it is a good idea to remove the two pivot stop cap screws and do a few 360 degree rotations of the fork while you pump in grease. If while doing it you don't grease exiting at the top and the bottom bushing, you should really consider disassembling and inspect it well because you likely aren't fully lubricating both bushings.

To the OP (and anyone else that owns an RV they didn't build). You really should have a copy of the plans and build manual. Once an RV is flying, it is basically the Maintenance Manual and Parts Catalog. You can buy a digital copy for just $10.
Better yet, if shopping for a second hand RV, be sure and get all of the build documentation with the airplane if possible.
 
Question, Its all new to me,,, I just purchased a RV-7A, I find the nose gear stiff to move with hand held tow bar, back and forth,, can you let me know if its normally that stiff ?,should go left and right with ease? does it require grease,?
is there any adjustments that can or should be made? appreciate comments, Thanks David

Just a F.Y.I......The break out force is set with the wheel off of the ground.

Part of the problem with "stiff to move" with the tire on the ground and using a tow bar is low tire pressure.
 
Hi Scott,, now I fully understand with the info you have given, also thanks to everyone on this subject that has given excellent advice, Thanks
David
 
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