31 tires?

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alaskan9974
Posts: 37
Joined: Wed May 06, 2020 6:48 am

31 tires?

Post by alaskan9974 »

Anyone running 31's?

Have had to pass up some gravel bars because the rocks were too big, anything over 6"+ gets pretty rough with the 26 goodyears I have. Wondering how you guys like the 29 or 31 ABW tires for this kind of surface.
'53 B-model SN:25712
Vertical
Posts: 151
Joined: Mon Oct 08, 2018 12:41 am

Re: 31 tires?

Post by Vertical »

I never really see much input on this forum for bush flying, so hopefully this helps.

I know guy with an o360 and 31" ABW. He says 29's are probably the right tire.
I have another friend who is on his second pair of 26" ABW. They are more capable than the 26" good years (although not that much for the price difference). I think he wishes he had gone 29's (but won't admit it). The 26's are probably the perfect "side country" tire.

When I wore through my 26" good years, I bought 29's. No regrets whatsoever. I think it's the right size for my o300 on lady legs for actual "back country" flying. Before commiting I obsessed over the added weight (these are 34# per tire with the extra tread) vs the benefit of more angle of attack and lower stresses on the airframe and gear.
To make up for the extra weight, I stripped out the interior (lost about 60#, then added a few goodies back in). The marshmallow landings are absolutely friendlier on the plane. The added performance from the increased angle of attack was instantly noticeable and I think negates some weight gain -anecdotally anyways. Standing on the tire to fuel is nice, but pushing the plane around got harder.

I still feel like a real #$$@ when landing my 65 year old baby on rocks bigger then 8" though, so try to keep it a little smaller...most of the time. If you are really going to spend a lot of time on big rocks, then the 31's might make sense, but I don't have first hand experience.

With any of them, definitely add a big tailwheel. Especially if you are in the big rocks. If bigger than 26's, then add the double pucks.

Here is a good comparison of the 26" Good Year vs an (over inflated) 29" ABW when I changed over.
IMG_2050 (2).jpg
Send us some photos of you landing on huge rocks if you go with 31's

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wabuchanan
Posts: 147
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Re: 31 tires?

Post by wabuchanan »

Here I am, completely content with my 26" Goodyears and happy as can be.........Then you have to post a pic of a 29 comparison, that makes my brain think thoughts that my pocketbook cringes at. :?

Thank goodness I've got awhile before the 26's wear out...
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1950 170A N5776C SN:19730
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johneeb
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Re: 31 tires?

Post by johneeb »

one 31 and one 26.jpg
This set up will work well if you always land with a left cross wind!
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John E. Barrett
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Vertical
Posts: 151
Joined: Mon Oct 08, 2018 12:41 am

Re: 31 tires?

Post by Vertical »

wabuchanan wrote:Here I am, completely content with my 26" Goodyears and happy as can be.........Then you have to post a pic of a 29 comparison, that makes my brain think thoughts that my pocketbook cringes at. :?

Thank goodness I've got awhile before the 26's wear out...
I hate to say it, but the real pocketbook cringe happens after you buy the 29's...Right about the time the mortgage is due.
dteal
Posts: 2
Joined: Tue Oct 29, 2019 11:38 pm

Re: 31 tires?

Post by dteal »

wabuchanan, what gear are you running? I want to go to 26" on my 52B but I've heard they will wobble in flight with the early gear. Running 850's now and they will dance around once in a while but not bad.
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GAHorn
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Re: 31 tires?

Post by GAHorn »

HERE’S what I want to see installed sometime:
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'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
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TFA170
Posts: 135
Joined: Tue Jan 26, 2016 3:18 am

Re: 31 tires?

Post by TFA170 »

GAHorn wrote:HERE’S what I want to see installed sometime:
I've seen a set (not installed) - I'll try to get pics when I'm there next.
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