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.
31 tires?
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Re: 31 tires?
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 #$$@ when landing my 65 year old baby on rocks bigger then 8" though, so try to keep it a little smaller...most of the time. If you are really going to spend a lot of time on big rocks, then the 31's might make sense, but I don't have first hand experience.
With any of them, definitely add a big tailwheel. Especially if you are in the big rocks. If bigger than 26's, then add the double pucks.
Here is a good comparison of the 26" Good Year vs an (over inflated) 29" ABW when I changed over. Send us some photos of you landing on huge rocks if you go with 31's
softened language by mod
I know guy with an o360 and 31" ABW. He says 29's are probably the right tire.
I have another friend who is on his second pair of 26" ABW. They are more capable than the 26" good years (although not that much for the price difference). I think he wishes he had gone 29's (but won't admit it). The 26's are probably the perfect "side country" tire.
When I wore through my 26" good years, I bought 29's. No regrets whatsoever. I think it's the right size for my o300 on lady legs for actual "back country" flying. Before commiting I obsessed over the added weight (these are 34# per tire with the extra tread) vs the benefit of more angle of attack and lower stresses on the airframe and gear.
To make up for the extra weight, I stripped out the interior (lost about 60#, then added a few goodies back in). The marshmallow landings are absolutely friendlier on the plane. The added performance from the increased angle of attack was instantly noticeable and I think negates some weight gain -anecdotally anyways. Standing on the tire to fuel is nice, but pushing the plane around got harder.
I still feel like a real #$$@ 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. Send us some photos of you landing on huge rocks if you go with 31's
softened language by mod
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- wabuchanan
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Re: 31 tires?
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...

Thank goodness I've got awhile before the 26's wear out...
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1950 170A N5776C SN:19730
- johneeb
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Re: 31 tires?
This set up will work well if you always land with a left cross wind!
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John E. Barrett
aka. Johneb
Sent from my "Cray Super Computer"
aka. Johneb
Sent from my "Cray Super Computer"
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Re: 31 tires?
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.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...
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Re: 31 tires?
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.
- GAHorn
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Re: 31 tires?
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.
An originality nut (mostly) for the right reasons.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.

- TFA170
- Posts: 135
- Joined: Tue Jan 26, 2016 3:18 am
Re: 31 tires?
I've seen a set (not installed) - I'll try to get pics when I'm there next.GAHorn wrote:HERE’S what I want to see installed sometime:
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