It is a good thing these break off easily, or I would have crashed on the tree roots on some of the mountain bike trails I ride.

I made replacement "foot" out of 14 gauge flat sheet metal.  It is about 3" high with a 1 1/4" tab folded back at the top.  It is 2 3/4" wide at ground contact.  I use a 3" hose clamp to mount it under the frame.  I loosen the clamp to remove it for riding...leaving the clamp retightened on the frame (not in the way of anything with the clamp screw above the frame tube).  I bent the tab, and shaped a little curve in it (to match the bottom of the frame tube) by hammering it over the edge of a railroad track (it makes nice curves for this).  It is very stable and solves the problem.  Do NOT try using anything thinner than 14 gauge STEEL.

I tried to post pictures, but the system won't let me, even though they are small size files. 

I usually ride a local mountain bike trail that is about 7 miles out-and-back.  The trail is 2.7 mile from my house, and so a full "loop" is a little over 12 miles.  I can do three of those "loops" and still have enough battery to climb the steep hill back to my house. 

I do ride the grades on the trails in 2nd gear, in order to keep my speed above 8 mph as much as possible.  It seems to be more efficient than slowing down and riding in 1st gear.

I have seen 39 miles on one charge, and still showed two bars (except at full throttle...where it would drop to one bar.)

To be completely honest....at my age, the "butt" gives out before the "batt" does!

In my earlier life, we had occasion to check various road surfaces.  We discovered that all of them (and especially pavement) had considerable rippling effect from heavy vehicles use.  At very high speeds we could actually see the surface fluctuations using an FFT spectrum analyzer with a magnetic G-pickup on our vehicle. 

Interestingly, the slight variation in rolling tire circumference could be seen as periodic variation of vibration intensity (often 7-9 second cycles at normal highway speed.)  Most vehicle owners thought they were feeling intermittent bad patches in the road, but it was really their own tires getting in and out of "vibration sync"!

You might want to try "coast down" tests at various air pressures, to get some comparative data.  You can find good instructions/methods on the internet.

For longer distances, we used Google Earth to read elevation points.  You can calculate distances using the "1 minute of arc = 1 nautical mile (about 6000 feet)" rule.  You can look for road sections that are easy to distance measure on the screen (exactly east-west, or north-south).

Longer test sections can really help balance useable results.  Repeatability is everything with this kind of testing.

Here is something fun and it might work for you.  The black "large diameter" Sched 40 ABS pipe (Lowes, Home Depot, etc.) can be cut and shaped with a method a friend showed me.  A hacksaw blade cuts it easily, and you can flatten or reshape with a propane torch, gloves, and a bucket of water.  You may find an ABS fitting long enough to reshape, instead of buying a long pipe that would be mostly wasted.

The trick is to fan the flame back and forth over the area you want to shape, but never let the visible portion of the flame rest on the ABS (or PVC if you want white).  I keep the flame several inches away, never stopping to change direction until I am away from the material.  Use patience to build the heat slowly, testing flexibility occasionally while wearing the gloves.  When you have an area hand shaped as you want, plunge it in water and it sets up quickly.  You could even press the softened material against the frame tube, to make a perfect fit for your guard.  It won't be hot enough to hurt the paint.

For complex shapes, work the heat in individual areas and shape the areas separately.

You could attach your "guard" using cable ties (the strong thick ones would be best).  I used this method to make a "replacement" for the broken off folding-support under the crank area (broke it off on rocks and tree roots on the mountain bike trail).

This stuff is really tough, even after heating and reshaping.

This stuff reminds me of a problem a friend had while working on an enclosed trailer (used for supporting Pacific Crest Trail maintenance crews).  After installing solar panels and hooking up LED light systems, he was seeing voltage on circuits, when nothing was turned on and the battery was disconnected.  It turns out that LED lights can actually generate a tiny current flow when they are exposed to sunlight.

I have also seen LED lights (in my house) which can turn on or off when a ceiling fan is powered up. 

Perhaps coiling the wires is making an inductance loop that "reads wrong" in the control system?  I wound my extension wires around aluminum tubes and have not had Code 25.

Strange stuff, I guess.

That video sounds like mine did when the front wheel bearings were flaking.  You hear and feel it in the handlebars.

Beaded tire removal: 

Step 1:  After removing valve core (all air out of tube), using the spoon end of tire iron, lever the bead over the side of the rim.

Step 2:  Turn the wheel over and lever the other side of the bead over the other side of the rim.  The wheel rim should now be completely inside the tire.

Step 3:  Hold the wheel vertical, with the valve stem sticking up through the rim, at the bottom.  Push the rim down all the way into the bottom of the tire.

Step 4:  You will now have a large gap between the top of the rim and the upper bead areas of the tire.

Step 5:  Simply pull the rim out of the tire, at the top, and you will not need to use tire tool.

Reassembly is this method reversed.  Start with tube inside tire, valve step at the bottom.  Use the flat end of tire tool to spread the beads far enough to slide the rim down between the beads.

The flat end of the tool is used to lever the bead back over the side of the rim.  Flip the tire/wheel over and lever the other side back on, the same way.

This method prevents pinching the tube between tire and rim during removal or installation.

It is the method taught by Husqvarna, clear back in the days of their motocross championship tour teams.  They demonstrated it (for local mechanics and dealers) all across the U.S. back in the early 1970s.  Many of you probably did not get to participate in those dealer/team training exercises.

This method works even easier on tubeless tires.

Agree!  on edge seems to help, for me.

Added note:  The rear wheel bearings are better than the front....have not seen or heard of any problems there.  Those are part of the motor, as provided for Rad, and certainly not the cheapo type that are in the front wheels.

The cone flats are 15mm (thin) wrench.  I made one by grinding down a forged 15mm open end wrench.  The stamped metal type will NOT do the job.  Only grind one side, to give a flat side that will fit close to the hub/seal area.

The outer (locker) nuts are 17mm.  My best results are to NOT disassemble the right side nuts (which have the cone nut and two locker nuts).  Use a pair of 17mm wrenches on the right side, and the 15mm and 17mm on the left side.  Unscrew the left outer (17mm) lock nut, if you can, from the 15mm cone nut.

I have done 4 of these bikes and only one would come apart this way.  Usually, the right side wrenches can be rotated to turn the shaft out of the left side cone and single nut (while they are still stuck together).  The left side nuts unlock as you reach the ends of the hollow axle threads.  The primary tension on the left outer nut (17mm) is keeping the left cone nut from actually distorting the axle threads.  I am squeezing the two nuts in a position that is trying to unlock them, as I unscrew the entire axle from them.

I have not had any damage occur using this method.  I leave the right side nuts in place, to be sure that I am not moving the front wheel sideways, in relation to the right side mount location, as delivered when new.

I use my bench vise, rotated about 45 degrees, to clamp the front tire (inflated to about 40 psi), so that I can manage the 4 wrenches by myself.  It really helps to have another person.

Don't get too crazy trying to lock the left outer nut back against the 15mm  cone nut.  Give it a firm set and it absolutely stays in place.

Replace the 6mm plated ball bearings with higher quality hardened bearings.  Note that the "seals" (such as they are) simply pry out easily with a flat screwdriver.  Clean out all the old grease, install the 9 new bearings (on each side), the push the seals back in place.  I use a small flat punch, gently tapped with the screwdriver plastic handle, to set the seals.  They are very easy to install.  Do NOT use a hammer!

I am having good luck with Mobil 1 synthetic grease.  I have used it in motorcycle wheels and steering heads for about 50 years and it is very water proof.

For my 5'2" wife, I shortened the bottom end of the inner "tube" of the handlebar mount and eliminated the screw in the upper slot.  Then I rotated the handlebars back and repositioned all the levers and screen, and such.  The grips can be rotated by grabbing with both hands and twisting slowly. 
This got her down to a useful height.  These are sit-up bikes, and you don't need to lean forward to pedal and climb hills.  All you shorter folks have the advantage with electric power....it goes up hills better (than us taller, heavier folks.) 

I am really happy with the Mini ST and have over 1700 miles on mine (of which 1000 miles of it is on local mountain bike trails).

We use Wingman bar end mirrors, which just pop out of the rubber socket if you crash (me), or bang them around when folding and loading.  For trail use, wrap a couple turns of black electrical tape around the plastic ball end, so that they will not constantly jiggle out of place.  We have some pretty fast Mountain bike and e-Mountain bike riders on the trails, and so I watch the mirror to get out of their way.

I did break off the little aluminum loop under the frame (used to support the bike when folded).  I made a piece of heavy wall ABS pipe into a little stand that mounts with a single bolt, on the occasion I need to fold the bikes to carry inside the back of my Jeep (Wrangler 4-door).  That little loop bends or breaks pretty easy when powering over rocks or small logs.  You can make a simple mount that goes onto the big frame tube with a large hose clamp.

The Mini cannot be ridden as fast and comfortable as a Rover (off road), but it sure does climb well with the 20" wheel size.  I ride slow enough to enjoy the scenery and it really works well.  I ride with folks on Rovers, and the climbs are easier for me (despite my 75+ years and some old damage from a Viet Cong rocket).

I think my Mini ST is really good entertainment for the money, especially for those of us who should not be trying to ride too fast, off-road. 

Steel screws into aluminum is ripe for dissimilar metal reaction (corrosion).  The "non-permanent" loctite is a reasonable. solution.  It makes for a better chance of getting the bolt out, if it isn't tried for years!  This is common throughout many industries, for cases where items may be added or changed at some future date.  It is certainly good practice for some product which is likely to be washed with that most dangerous solvent on our planet:  WATER!

I do find the bolts, used by RAD, are a little rough in the thread cut.  I have tried running them into some good quality metric nuts (saved from old Honda motorcycles and such) to see "what's up?"  It is easy to tell they are a little rough (and obviously not "rolled thread" quality).

I clean them up with my metric tap and die set, and have no problems.  The tip for tap cleaning the powder coated threads is right on the money.  Just remember to use a little non-permanent loctite on them, so they won't corrode in place, permanently.

All of our Mini ST will occasionally do this, and I have learned to give both brake levers a quick apply and let them "snap" off.  If I just pull and ease off the levers....still no power or PAS.  The quick flick of the levers seems to be the answer.  In fact, I have learned that it doesn't seem to matter which lever I flick!

It seems to occur most often on places on the mountain bike trail where I am standing on the pedals, downhill fast coast, with the brakes lightly applied.  I ease off  the brakes to begin climbing the next hill...and....no power!

A couple quick brake lever flicks, and everything is back.

The latch pivot tends to slide a little out of place.  I just use a flat blade screwdriver and slide it down a bit so that the lever doesn't jam against the safety lock mount.  It moves easily....no big deal.

Thanks for your reply.  It clears my mind that it is just the conditions I ride, and not something inherently weak about our brakes.