Wheels

[Highflight]

My experience with low grade trolly, cart or toy wagon wheels with plastic bearings is that the bearings wore out quickly and were prone to melting in extended taxi testing.

We have recently upgraded all of our ultralight's aging 4&5"dia Azuza plastic wheels to 6"dia Douglas (DWT) Alumilite one piece wheels. I installed 2-ply tires instead of the OEM 4-ply, the all up weight of the new larger tires and aluminum wheels is comperable to the original setup. The Azusa wheels served well for the last three decades but were showing their age, the plastic bearing races were very loose, the wheels had obvious signs of U/V ageing and embrittlement.

 

[pictsidhe]

I'm a bit dubious of the ability of standard MTB wheels to take much side load. Build some custom wheels with much wider hubs and you'll have much tougher wheels, though.

3 decades seems ok for the cost of the Azusas to me. I am planning better bearings for any Chinese plastic wheels I may use. I am staying away from the wheel is the bearing type wheels. My plastic wheels look like they may save me 3lb and $100 over the metal Azusa ones that size. Seems worth trying out.

 

[lr27]

I'm a bit dubious of the ability of standard MTB wheels to take much side load. Build some custom wheels with much wider hubs and you'll have much tougher wheels, though.

3 decades seems ok for the cost of the Azusas to me. I am planning better bearings for any Chinese plastic wheels I may use. I am staying away from the wheel is the bearing type wheels. My plastic wheels look like they may save me 3lb and $100 over the metal Azusa ones that size. Seems worth trying out.

You'd probably have to make custom hubs or modify existing ones anyway. I doubt if most hubs have room for, say, a 3/4" or 1" diameter axle going through, and they'd need a different sort of bearing as well. Plus, of course, they're a bigger diameter than you need but probably have less give than the tires you'd use on an Azusa wheel. Unless you go for those really fat tire ones, which you'll then have to drag through the air at all times.

 

[Highflight]

Watch the Red Bull Soapbox races, the bicycle wheels generally don't do too well in the turns. The Azusa wheels are two piece and require a tube, we now use 3/4" "precision sealed" bearing and a solid 7075 axle stub. Obviously wheel/tire choice is has a lot to do with the surface you will be operating off of, I have done a few unplanned out landings in cow pastures and rough open land, I have been thankful I have sprung mains and I wasn't using the smallest wheel possible.

 

[oriol]

As lr27 points MTB wheels would look great in something like a Fokker Eindecker but not so quite in many other airplanes, even if you go with 22" wheels which are rare for a MTB size. Anyway, bike spokes were designed for aircraft, back in the day, and even if they are not listed in the Aircraft Spruce catalog they can do wonders in a Part 103 aircraft but certainly not in a "light" sport airplane like a Cessna.

Oriol

 

[Highflight]

As lr27 points MTB wheels would look great in something like a Fokker Eindecker but not so quite in many other airplanes, even if you go with 22" wheels which are rare for a MTB size. Anyway, bike spokes were designed for aircraft, back in the day, and even if they are not listed in the Aircraft Spruce catalog they can do wonders in a Part 103 aircraft but certainly not in a "light" sport airplane like a Cessna.

Oriol

Martin makes 16" BMX style cart wheels which may apeal to some builders. Gokart wheels are designed to handle both speed and side loading, not sure how round a cart wheel might be at 30mph.

 

[lr27]

You can get metal, spoked BMX wheels, which I suspect would be much tougher and possibly lighter. Particularly since good ones would be designed for severe abuse. Might be better, though, to get the rims, hubs, and spokes separately. Maybe use parts meant for the front wheel of recumbent tandems, which are likely to be smaller and stronger than normal bike wheels. Something meant for the side loads of a recumbent trike might be even better, particularly the ones on a cantilever axle.

I doubt that plastic wheel in the picture could take much fo a side loading. Or, at least, it looks like plastic to me.

In any case, these wheels probably won't have all that much give, so the suspension will have more work to do.

I expect some moped or motorcycle wheels would be fine for LSA's, depending on the required speeds. Maybe something from a motorcycle side car, since they don't need a fork and are presumably designed for side loads.

 

[oriol]

The pterodactyl ultralight used plastic rims like those Highflight mentions but MTB are much more resistant and convenient.

The great majority of recumbent trikes use standard MTB wheels and can take the side loads without any problem; think about cargo bicycle speeds. Front kart wheels lack brakes and are not particularly cheap and use slick type covers, rear kart wheels have a spider kind of fitting that makes them unsuitable for an axle support.

It is much more cheap and simple to go straight to the aircraft spruce catalog or to contact any aircraft manufacturer than to recycle John Deere/Kart wheels or other non aero wheels; motorbike and Quad wheels are too heavy for aircraft use.

Oriol

 

[blane.c]

Here are some idea's.

 

[lr27]

The pterodactyl ultralight used plastic rims like those Highflight mentions but MTB are much more resistant and convenient.

The great majority of recumbent trikes use standard MTB wheels and can take the side loads without any problem; think about cargo bicycle speeds. Front kart wheels lack brakes and are not particularly cheap and use slick type covers, rear kart wheels have a spider kind of fitting that makes them unsuitable for an axle support.

It is much more cheap and simple to go straight to the aircraft spruce catalog or to contact any aircraft manufacturer than to recycle John Deere/Kart wheels or other non aero wheels; motorbike and Quad wheels are too heavy for aircraft use.

Oriol

I'd expect a recumbent trike to be a whole lot faster than a cargo bike.

Just checked the Azusa prices on Aircraft Spruce. Probably hard to beat if they meet your projects needs. OTOH, if your ultralight weighs 251 lbs without wheels...

 

[pictsidhe]

Martin makes 16" BMX style cart wheels which may apeal to some builders. Gokart wheels are designed to handle both speed and side loading, not sure how round a cart wheel might be at 30mph.

Those look exactly like the rear wheels on 'big wheel' push mowers. They break.

 

[blane.c]

At the forces they break at, could they be part of your landing gear energy absorption?

 

[pictsidhe]

The side loads of mowers break them. I seriously doubt that they are up to the job. My plastic wheelbarrow wheels are far sturdier, but I'm still going to test them. Wishing I'd bought 3 in case I damage one in testing...

 

[Tiger Tim]

Wishing I'd bought 3 in case I damage one in testing...

If I damaged one in testing I’d be regretting buying two...

 

[Rockiedog2]

Those look exactly like the rear wheels on 'big wheel' push mowers. They break.

yeah I wouldn't try those. they only got one stiffening flange per spoke check this one out that was mentioned earlier...I accidentally destruct tested it, it'll hold up to normal ground loops on a legal Eagle but not landing backwards and sideways. Naw.

https://www.leadingedgeairfoils.com/20-tuff-wheel-hub-special.html

 

[BBerson]

Harbor Freight has wheels. About 10" for $3 or $5 or something on sale.

 

[proppastie]

Harbor Freight has wheels. About 10" for $3 or $5 or something on sale.

https://www.harborfreight.com/catalogsearch/result/index/?AttribSel=Wheel+Type%3D%27View+All+Wheels%27&CatPath=All%2BProducts%252F%252F%252F%252FUserSearch%253Dwheel&RequestData=CA_AttributeSelected&dir=asc&order=EAScore%2Cf%2CEAFeatured+Weight%2Cf%2CSale+Rank%2Cf&q=wheel

 

[pictsidhe]

Harbor Freight has wheels. About 10" for $3 or $5 or something on sale.

Stripped and weighed in my first post. I didn't bother with a picture.

 

[pictsidhe]

If I damaged one in testing I’d be regretting buying two...

If I destroy one in testing, they are no good. If they are fine at normal loads and remain roundish at crash loads with some damage such as distorting a bit, they are good. But testing to crash loads may damage them for normal use.

 

[BBerson]

Stripped and weighed in my first post. I didn't bother with a picture.

So what's wrong with steel wheels?
Could be sealed tubeless with black tire bead sealant.