Tires

[Smilin' Jack]

I posted this in the wrong area this morning so hopefully it is correct.

As I rolled the 7 into the hanger last night I noticed on my post flight that the left main is getting a little slim on the thread on the center, the outside and inside look great but I went ahead and ordered new tires and tubes yesterday.

I have only gotten 214 landings in 87 hours of flying since my first flight October 26,2013 and was wondering how many landing do you get out of a set of Van's tires?

Also how much pressure are you running in the tires? I was using 40 psi.

I have been trying to nail down my 3 point and wheel landings and make them consistant... The wheel landings are definitely more challenging.


Jack

 

[Kahuna]

I have only gotten 214 landings in 87 hours of flying since my first flight October 26,2013 and was wondering how many landing do you get out of a set of Van's tires?

Also how much pressure are you running in the tires? I was using 40 psi.


Jack

Jack,
Tire wear is not particularly dependent on landings per se, but at least as dependent on miles traveled(long taxi's to hanger) as well as other factors like differential braking vs rudder use, grass vs pavement, and the like. Tire pressure has as much to do with the amount of weight you normally run with. If your a full fuel load kind of guy with pax often vs a light load guy etc. So getting numbers is a game of shotgun and probably wont help you much.
Certainly if your obviously running out the centers then lower pressure will help that, but of course there is a trade off.
In the end it is what it is for you and your profile. Comparing tires is even a worse game with others. Its only a useful comparison relative to yourself.

 

[Russ McCutcheon]

I posted this in the wrong area this morning so hopefully it is correct.

As I rolled the 7 into the hanger last night I noticed on my post flight that the left main is getting a little slim on the thread on the center, the outside and inside look great but I went ahead and ordered new tires and tubes yesterday.

I have only gotten 214 landings in 87 hours of flying since my first flight October 26,2013 and was wondering how many landing do you get out of a set of Van's tires?

Also how much pressure are you running in the tires? I was using 40 psi.

I have been trying to nail down my 3 point and wheel landings and make them consistant... The wheel landings are definitely more challenging.


Jack

I find the tires from Van's are as good or better then others I have tried, even the more expensive ones, 200 hours and 400 landings is typical for me, I turn rotate them halfway. RV-4 1065lbs empty, 30psi, 99.9% pavement. I suspect I would be better off with less toe in but it is what it is.

 

[Sam Buchanan]

I posted this in the wrong area this morning so hopefully it is correct.

As I rolled the 7 into the hanger last night I noticed on my post flight that the left main is getting a little slim on the thread on the center, the outside and inside look great but I went ahead and ordered new tires and tubes yesterday.

I have only gotten 214 landings in 87 hours of flying since my first flight October 26,2013 and was wondering how many landing do you get out of a set of Van's tires?

Also how much pressure are you running in the tires? I was using 40 psi.

I have been trying to nail down my 3 point and wheel landings and make them consistent... The wheel landings are definitely more challenging.


Jack

Over the years tire pressure in the 24-28 lb range has been found to work well with RV-6/7 and helps inhibit gear shimmy.

Typically the left tire wears quicker and it will be the outside edge of the tread that goes first. That is why we often "flip" tires in order to get full service life.

Wearing out the center tread on a RV-6 or 7 usually indicates you are using considerably more pressure than necessary.

Interesting that you are finding wheel landings more challenging--many of us have adopted wheel landings because they are more consistent than hitting the very small sweet spot that a smooth three pointer requires, especially when DA starts climbing in the summer and/or the wind is gusting. Full flaps will raise the tail and make wheel landings easier. Wheelies more often than not are actually a bit more tail low than what you might see with a J-3, but airspeed control is not quite as critical as with a three pointer.

But go with whatever works for you.

I moved your thread to the RV Maintenance forum.

 

[Smilin' Jack]

Thanks Mike,Russ,Sam

Think I'll run a little less pressure

Sam missed you at Guntersville, saw your plane but not you, we were with Bill
In his TriPacer, with Rob and Clyde, mine was still down from the smoke installation
Jack

 

[Walt]

I'm a big fan of running pressures IAW with tire manufacturers recommendations. Higher pressures help eliminate flats and will make your tires last longer. I run Goodyear FCII's with 45-50 psi in the mains and 45-55 psi in nose wheel.

http://www.desser.com/pressurechart.php
http://www.goodyearaviation.com/resources/pdf/aircraftmanual.pdf

(Some of the worst advise I ever got as a kid was to run my rear motorcycle tire with lower pressure to avoid wearing out the center, after about half a dozen flats at high-way speeds that almost killed me, I finally figured out that was really bad advise. Higher pressure elimated the flats.)

 

[Sam Buchanan]

Thanks Mike,Russ,Sam

Think I'll run a little less pressure

Sam missed you at Guntersville, saw your plane but not you, we were with Bill
In his TriPacer, with Rob and Clyde, mine was still down from the smoke installation
Jack

Sorry I missed you, Jack, we'll try to make connections next month. Guntersville is turning into a nice, 2nd Saturday breakfast destination.

I'm a big fan of running pressures IAW with tire manufacturers recommendations. Higher pressures help eliminate flats and will make your tires last longer. I run Goodyear FCII's with 45-50 psi in the mains and 45-55 psi in nose wheel.

http://www.desser.com/pressurechart.php
http://www.goodyearaviation.com/resources/pdf/aircraftmanual.pdf

(Some of the worst advise I ever got as a kid was to run my rear motorcycle tire with lower pressure to avoid wearing out the center, after about half a dozen flats at high-way speeds that almost killed me, I finally figured out that was really bad advise. Higher pressure elimated the flats.)

Yes, I agree that recommended pressure is usually best. However, 45-50 psi in the mains of a RV6 or 7 will often result in gear shimmy that can border on violent. Various attempts have been made over the past twenty years to tame the oscillation--wood dampers and/or balanced wheel pants being the most common. But the only remedy that consistently works is running ~25 psi. The factory knows this and recommends this pressure in the tail dragger mains with the Wittman gear. This does not apply to the RV-8 or the nose-draggers. There is something about the tailgear geometry that excites the spring gear and causes shimmy when running high pressure (45-50) in the tires. I've used up to 35 psi but try to stay out of the speed range where shimmy occurs. Twenty-four psi keeps the shimmy under control at all speeds.

 

[GaryK]

Goodyear Flight Custom III

I'm on my 3rd set, averaging 475 hours or 3 years. I don't have the exact number of landings but average flight is .7 hours.

99% hard surface

Mains at 38 lbs
Nose at 44 lbs

N715AB
1140 hours

Gary

 

[az_gila]

I'm a big fan of running pressures IAW with tire manufacturers recommendations. Higher pressures help eliminate flats and will make your tires last longer. I run Goodyear FCII's with 45-50 psi in the mains and 45-55 psi in nose wheel.

http://www.desser.com/pressurechart.php
....

But those numbers are not the tire manufacturers recommendations.

They are the maximum allowable pressures - quite a difference.

From the chart -

Maximum Rated Pressures
Always consult with your owners manual for factory recommended pressures !

 

[rvbuilder2002]

I agree.
Operating an RV at the maximum rated pressure of the tire will be excessive.
Particularly in the airplanes that are operating at well below the max. weight rating of the tire.

55 PSI in the standard nose wheel of the two seat RV's (not counting the RV-12, it would induce a whole different set of issues on that model) is just asking for shimmy in my opinion.

 

[Walt]

I do operate quite often at or near gross weight and have had no problem with tire wear or shimmy, guess I'm just lucky

I will agree that if you've done everything to eliminate the shimmy first that reduced tire pressure is an certainly an option but IMO it should not be used as an easy fix for other problems.

I run the pressures in my car tires high/max for the same reasons, less heat/better wear/better mileage.

 

[rvbuilder2002]

I will agree that if you've done everything to eliminate the shimmy first that reduced tire pressure is an certainly an option but IMO it should not be used as an easy fix for other problems.

That I do agree with Walt.

Shimmy can have many different causes.
Common ones are wheel/tire out of balance or out of round (from sitting in one spot for extended period or just plain bad tire).

Don't use tire pressure to solve these type of problems.

 

[Smilin' Jack]

I only get a shimmy once in a while and it is usually around 30 mph when it happens. Perhaps only once in 30 landings.
I will reduce my tire pressure and see how it goes.

Thanks for all the replays.
Jack