Searching for 20mm thru-axle hubs

Hello,
I am building a tadpole trike with front disc brakes and am following the PDF instructions for the warrior racing trike. I am searching for 20mm 36H thru-axle hubs as described in the build plans on page 66. The plans state that these hubs are common and can be found for relatively cheap by the brand "Formula" however I can't seem to find much about these. All others I have found are over $100 each. Does anyone have any recommendations or links? Please do share.

The current best option I've found. (Is "KOOZER" a known brand?): https://www.ebay.com/itm/296352640811?var=594346316277
 
Please don't get fixated on specific parts mentioned in the plans , they were meant to be altered to use locally available parts and the plans were created some time ago the world moves on and other solutions are available.

You don't need 20mm thru axle hubs unless you plan on going off road or you are on the heavy side , 15mm through axle hubs are perfectly adequate or even old school BMX hubs with 14mm axles although these are harder to find with disc mounts.

Aliexpress I used this site when I ordered 4 for a quad I am building.

That trike also benefits from having the rear wheel stays triangulated to the main frame about 1/2 way down the seat back IIRC else a little to enthusiastic use could cause the frame to split.

I am sure someone who has built one will be along shortly with more guidance and tips.

Paul
 
They are vintage plans so that brand may have sunk without race by now. As far as I know ANY 36H 20mm through hub will be fine.
I used DMR front hubs ages ago and they were fine. I used precision tube as the axles to try and save weight.
These look more affordable?
 
I bought the exact same hubs that Danny linked from eBay, last month - $54.46 US for a pair, delivered.
They look fine, and I've already laced them to some 20" rims.
You will have a bit of fun, to get the outer axle sleeves off - I needed a slide hammer bearing puller :)
 
Those are nearly identical to the hubs I ordered from Ebay about 4 years ago and they have about 1,000 miles on them without any issues.

Something I did different from the manual with them though, instead of using a 14mm bolt or build up the weld on a smaller bolt, I used two "58104 Flange Bearing, Bronze 5/8 X 3/4 X 1 X 3/4-Inch". These worked great to hold the bolt/axle centered and when the nut is tightened the flange applies the pressure correctly to the hub and bearings so it doesn't lock down the bearing, etc.

I'll echo what stormbird said, I did triangulate the rear wheel supports as well as added a gusset to the front two wheel arms. I'm not overweight, but I wasn't an experienced welder and as i looked as "real" trikes and bikes they all had some triangulation on the rear and front wheel, I figured better safe than sorry.

I would also recommend that you make the rear wheel, horizontal support behind the seat, a little longer than the plans show. My first build was exactly the recommended length and I have a hard time finding tires with low enough tred, as there is very little clearance. On subsequent builds I made it slightly longer which gave me more room for more tire options and made adding a rear fender considerably easier.
 
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Give some thought to the rear hub also.
I originally got a nice looking QR rear cassette hub for this next project, but.............:(
When I tried my 8 speed cassette on it, it was obvious that the small 11 tooth cog was going to be right against the dropout - No clearance.
And since it was a QR, with just those little short axle stubs, not much I could do about it.

So, I poked around, and found this one :
It has an old-style solid axle, but built as a new-style free hub - The extra axle length will give a little breathing room for the cogs.
The solid axle might even be stronger, but I'm not enough of an engineer to be 100% on that.
 
Thank you all for your input. To be more precise, I’m using bits from the warrior plans such as the front axles and hubs but building my own electric tadpole trike with a rear hub motor. It will be able to seat two people side by side so I want to use 20mm axles and not have to worry about going off curbs or anything. (Profile photo is CAD work in progress) I have access to a lathe and so will likely turn the axles from steel shaft stock myself.

Is 32 or 36 spoke more commonly used for 20” rims? Hw much does this matter? I appreciate the recommendations, I am still leaning towards my initial Koozer hubs as I’m willing to pay a bit more for something that will arrive in California in a reasonable time. (We’ve all ordered something from china to save $5 that ends up taking a month to arrive…)

-Gavin
 
Ok that's some challenge , before you select the hubs [ i.e number of spokes ] I would find some strong rims that you like i.e double walled. Your choice will be limited in 20"

Seen this ? Elkions pedal car does most of what you want ?

Maybe better than a tadpole trike ? that rear wheel is going to be under some load without the stress of pedaling ?

Paul
 
I ended up going with these Sun Ringle 20in rims which were a good price and are a known manufacturer:

And these Koozer hubs:


Hopefully they work out!
 
Sun rims are excellent. I have a pair of Sun Black Label triple box after cheaper rims taccoed on me. 32h may be a bit short on spokes though given two people. I'd have opted for 36h but only because 48h are not made in 20mm (that I've seen). These rims and hubs were never designed with side forces in mind. Make sure you lace them nice and tight. You are right to go for 20mm hubs in such a case.

What size rear wheel are you using? Again two people's weight will put a lot of force into it, especially if you choose to corner enthusiastically as a taddy can. You may want to use a 20" rear for strength rather than anything bigger. If you want to go 26" or 700c give some thought to using two rear wheels. Each can be inline with the relevant pedals so more inboard than the fronts. The downside is weight but you are going electric so not too much of an issue.
 
Good to know about the Sun rims!

For the rear wheel I have a Weinmann 19mm wide 26” rim with a GMAC 10T rear hub motor. The motor is made by Grin Technologies in B.C. Canada and was laced by them as well. I have a 2.25” continental e-bike urban tire. According to https://www.bicyclerollingresistance.com/ the wider the tire the lower the rolling resistance so I went pretty fat. It’s not going to be an aero penalty in the back.

The whole rear wheel was quite pricey but I wanted something robust for this build. The hub motor was specifically designed for cargo bikes and has an internal planetary gear reduction and is capable of regen braking. I hope it doesn’t taco! Lateral g-force is my biggest concern.

Thanks for letting me info dump! I’m working on all of this for a YouTube video.

-Gavin
 
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