Rad Power Bikes Owners Forum

Rad Power Bikes Chat => Rad Modifications => Topic started by: Bob Mc on August 12, 2020, 08:37:44 PM

Title: Rad Runner Mods
Post by: Bob Mc on August 12, 2020, 08:37:44 PM
Some of the mods I made.
Second battery, with a 2P2T switch so I can use one or the other, or turn both off.
Wrapped the cables with swirl wrap, 8mm from Amazon. I think it looks better than the velcro cover.
The new controller from Bolton is a lot wider than original so I made a wider skid plate from aluminum.
The front wheel on the Runner swings all the way to one side or the other when on the center stand and off the ground. I saw a spring on the Rad Cargo Bike that holds the front wheel straight so I put a piece of rubber tubing from the fender bolt to the the frame. It works great, can't feel any control difference when riding.
Title: Re: Rad Runner Mods
Post by: Ryan on August 14, 2020, 02:08:30 PM
Awesome! Guess you'll never have range anxiety on your RadRunner  8)

Is the second battery sitting on a metal plate as well? That's a perfect spot for it.
Title: Re: Rad Runner Mods
Post by: Bob Mc on August 15, 2020, 11:06:49 AM
Howdy, I installed a thin plywood shelf resting on the rear frame crossover and put two small "L" brackets on the downtubes and mounted the metal shelf that came with the battery on the plywood. It uses the battery key lock.
It is really nice not worrying about electrons for getting home.
Title: Re: Rad Runner Mods
Post by: 992023515 on August 15, 2020, 06:34:55 PM
I would be interested in where you got the battery and a schematic of the wiring. Looks cool.
Title: Re: Rad Runner Mods
Post by: Bob Mc on August 16, 2020, 01:01:46 PM
Quote from: 992023515 on August 15, 2020, 06:34:55 PM
I would be interested in where you got the battery and a schematic of the wiring. Looks cool.
Howdy. The battery is from Amazon "Unit Pack Power" 48v 15 ah, $308. I had to do a slight frame mod to get it to fit. All dimensions are listed on Amazon so you could probably get one that fits without mods. The schematic drawings are poor. I took a Mechanical drawing class at the U of Fla a few years ago (1960), and lost a lot of lead since then. The DTDP switch is from NAPA, it is rated at 250V 15 amp and 120V 78 Amp, so I figured it would hold 48 volts. After full power for a few minutes it isn't even warm. I like it cuz the batteries are never in parallel, always separate.
Title: Re: Rad Runner Mods
Post by: Altema on September 01, 2020, 12:50:57 PM
Nice version of an auxiliary tank! Do you power down the display before flipping the switch?
Title: Re: Rad Runner Mods
Post by: Bob Mc on September 01, 2020, 12:56:42 PM
Quote from: Altema on September 01, 2020, 12:50:57 PM
Nice version of an auxiliary tank! Do you power down the display before flipping the switch?
I do turn off the display, key off the battery that was in use, flip the switch to the other battery, turn on the second battery, then turn on the display. That may be over cautious but works.
Title: Re: Rad Runner Mods
Post by: Altema on September 05, 2020, 10:13:28 AM
That's the way I would do it as well. You could technically run them in parallel since both battery packs are the same voltage. They balance out as they drain, but I think I would prefer they way you have it.
Title: Re: Rad Runner Mods
Post by: Count on September 27, 2020, 05:20:49 PM
Why not just use the Bolton dual parallel battery connector?

Quote from: Bob Mc on August 12, 2020, 08:37:44 PM
Some of the mods I made.
Second battery, with a 2P2T switch so I can use one or the other, or turn both off.
Wrapped the cables with swirl wrap, 8mm from Amazon. I think it looks better than the velcro cover.
The new controller from Bolton is a lot wider than original so I made a wider skid plate from aluminum.
The front wheel on the Runner swings all the way to one side or the other when on the center stand and off the ground. I saw a spring on the Rad Cargo Bike that holds the front wheel straight so I put a piece of rubber tubing from the fender bolt to the the frame. It works great, can't feel any control difference when riding.
Title: Re: Rad Runner Mods
Post by: Count on September 27, 2020, 05:55:17 PM
I Just became aware of this forum, and am enjoying and learning from it.   Some very interesting and informative posts here!  At the expense of sounding cocky, you have some catching up to do!  As of today, I have installed: 

-A Bolton suspension front end, 35 amp controller (mounted exactly where the original mounts, in a waterproof enclosure); A new TRUE 1000w Baffang motor (which makes a HUGE difference in power);  multi-adjustable handlebar stem/riser,  and color display, Three 2000w headlights (great for night beach and golf course rides!), custom Harley solo style seat with full 3 point suspension, normal stuff like fenders, racks, and front and rear collapsible milk crate style baskets, and OH, did I mention a 1000w front hub motor 4" x 20" wheel/tire (for extra umph in soft beach sand, where I ride), with individual throttle (and as I come to find, about an extra 5MPH in speed).  Currently I am installing  a 7 speed derailleur, and have the gear selector, cable, 7 gear cassette (came with the 1000w Baffang motor) installed, and working on the actual derailleur mounting: nearly there. (The chain currently rides on one of the gears in the cassette). Other misc. handlebar mounted junk like bluetooth speaker and mount for tunes, cell phone mount, beer can holder,  headlight switch, etc.  With the front throttle added, and a 7 speed gear selector, as well as the other stuff mounted to the handlebar,  I have had to add a few handlebar extensions but it looks pretty good. 

I know, I know, I am blowing hot air until I post photos!  I will take some soon!  What is next?  I am contemplating another battery, as range is modest with all of the extra junk (about 20-25 miles on the beach, mostly in PAS2).   I am not a speed freak, and am contemplating a second 48v battery, connected in parallel with the original for about 35A of power, OR an upgrade to a 52 volt second battery, simply mounted somewhere, but manually switched, unless I can find a cheap effective high amperage electronic battery selector!



Yeah, I could have bought a more expensive bike with some of these gadgets, but this has kept me busy through the pandemic, and I simply love designing, engineering and installing upgrades, especially when most are NOT bolt on parts intended for the RadRunner! 
Title: Re: Rad Runner Mods
Post by: wkindred on September 28, 2020, 06:41:40 AM


hey count!

how were you able to mount the bolton suspension fork?

other reviews claim it can't (easily) be done...
Title: Re: Rad Runner Mods
Post by: Count on September 29, 2020, 02:28:22 PM
It went on very easily.  I had to make a new front axle, which needed to be longer to accomodate the fender supports.  It cost $10 for a stainless threaded rod.  I had to transfer the threaded insert from the Bolton fork stem and insert it into the Bolton one, simple stuff.  Even the headlight mounted right up, as well as the front Rad rack.  I also love my home designed seat: So comfortable, with no fatigue or butt soreness!  It has 2 coil springs, and a suspension seat post, all actively cushioning the ride, along with the Bolton front end.  The brake caliper mounted right on, once I removed one part.  I had to fabricate 2 aluminum spacers from tubing to mount the caliper, but a hand full of washers would work.   Here are some photos:




Quote from: wkindred on September 28, 2020, 06:41:40 AM


hey count!

how were you able to mount the bolton suspension fork?

other reviews claim it can't (easily) be done...
Title: Re: Rad Runner Mods
Post by: Ryan on September 29, 2020, 06:44:35 PM
Well I think you win the award for most unique looking RadRunner. Thanks for sharing.
Title: Re: Rad Runner Mods
Post by: sc00ter on September 29, 2020, 08:26:29 PM
Yes, that is cool!
Title: Re: Rad Runner Mods
Post by: wkindred on September 30, 2020, 06:24:42 AM


count -

i noticed you mounted the front fender backwards, was this due to the fender support spacing?
Title: Re: Rad Runner Mods
Post by: massassi on September 30, 2020, 09:27:29 AM
super cool Count!
Title: Re: Rad Runner Mods
Post by: Andy Finney on September 30, 2020, 09:54:16 AM
I can't believe that were not using the built-in compliment here...That's RAD!
Title: Re: Rad Runner Mods
Post by: massassi on September 30, 2020, 11:26:01 AM
Quote from: Andy Finney on September 30, 2020, 09:54:16 AM
I can't believe that were not using the built-in compliment here...That's RAD!

Groan ...but you are correct
Title: Re: Rad Runner Mods
Post by: Count on October 02, 2020, 04:05:17 PM
YOU, Sir, have a sharp eye!  Funny thing is, it was mounted on the bike that way when i bought it (I bought from a bike shop, assembled)!  I never have looked at it critically, and I can now see it is definitely backwards!  I have been wondering why I am getting some splashes when I go through puddles!  The first thing I am going to do tonight is to look into that!  If I can flip it easily enough I will!    Thanks!

Quote from: wkindred on September 30, 2020, 06:24:42 AM


count -

i noticed you mounted the front fender backwards, was this due to the fender support spacing?
Title: Re: Rad Runner Mods
Post by: Count on October 02, 2020, 04:11:42 PM
Thanks!  What may not be apparent is that I also have an independent throttle controlled 1000w hub motor on front, (New, not in the photos), and am finishing up the installation of 7 speed gear shift ability.  It is a one of a kind.  I LOVE my RadRunner, largely because it is so customizeable, and is build so solid.  With ALL of my modifications, I have not had to drill a single hole in any part of the frame or cut anything, which is a real tribute to the basic design and construction!  If I had to choose my favorite single customization, it would be the seat!  Being sprung makes it SOO much more comfortable to ride!

Quote from: Ryan on September 29, 2020, 06:44:35 PM
Well I think you win the award for most unique looking RadRunner. Thanks for sharing.
Title: Re: Rad Runner Mods
Post by: wkindred on October 05, 2020, 12:26:16 PM
count -

another inquiry...how long are the 2 aluminum spacers you fabricated for the front brake caliper mount?

thanks again!

      - will
Title: Re: Rad Runner Mods
Post by: Bob Mc on October 05, 2020, 08:31:07 PM
Howdy, I just installed the Bolton forks also. I used 1/2 inch brass spacers. So far the brakes work well. The forks are fantastic, compare a Jeep to a limo on a washboard gravel road. The fender struts required a lot of bending to fit to the fork holes.
Title: Re: Rad Runner Mods
Post by: Jman on October 05, 2020, 10:13:00 PM
For those that have successfully installed a Bolton suspension fork on a Radrunner, can you go over the process in a bit of detail?  I'm sure there are many of us that would love to do this mod, myself included. ;D
Title: Re: Rad Runner Mods
Post by: Jman on October 06, 2020, 12:21:49 AM
I've just read Rad Power will sell you the Radrunner Plus suspension fork for $150.  Might be worth looking into for anyone wanting to do that mod.
Title: Re: Rad Runner Mods
Post by: wkindred on October 06, 2020, 10:03:58 AM
sadly, the radrunner plus suspension fork availability rumor is just that, rumor. spoke with kharis goldman at rad power bikes. the radrunner plus suspension fork is not compatible with the radrunner 1 and is not being sold separately -

"Hey Will,

Thanks for reaching out! The RadRunner 1 ebike was designed with a rigid front fork, which is what we've tested and approved under warranty. We actually had to change the design of the RadRunner Plus slightly, in order to accommodate that suspension front fork without the front wheel hitting the frame.

Therefore, the suspension front fork of the RadRunner Plus is not compatible with the RadRunner 1's frame, even though they look very similar. Also, the suspension front fork is not sold separately from the ebike.

Hope this provides some clarification, and let us know if you have further questions! You can also check out our Help Center in the meantime, as it can be a great resource.

Best,

Kharis Goldman
Rad Power Bikes
Customer Experience Associate"

:-\
Title: Re: Rad Runner Mods
Post by: Jman on October 06, 2020, 12:31:57 PM
I've just found out that the person who claimed that Rad will sell the fork was the person that purchased it from Rad themselves. He thinks they sold it to him because he owns a Radrunner Plus and a Radruner.  He know's it might not fit but will try it anyways.  Guess we'll find out.
Title: Re: Rad Runner Mods
Post by: Bob Mc on October 06, 2020, 01:16:05 PM
For Jman
Here is a step by step of my installing the Bolton forks.
1. The forks arrived with only the forks in the box, no instructions, measurements or anything, no air pressure recommendation. Bolton sells an installation package but are out of stock.
2. You need a star nut to screw in the top bolt into the stem. Amazon has a set of 5 for $7. I didn't have the patience (two days) so I took the old one out of the stock fork. Unless you have a few tools it isn't recommended. I had to file off a weld at the bottom of the stem to drive the star nut down through it. In driving the star nut down it compresses it and you have to expand it once you get it out so it will fit tightly into the new stem.
3. The new fork stem is 2 1/8 inches shorter than the old one, scary at first. But the new one fits in the bike frame perfectly without the conical spacer (surprisingly 2 1/8 inches).
4. I took off the old lower bearing race from the stock fork and put it on the new fork. The fork stem was just right, maybe a hair smaller diameter stem than the old fork.
5. Put in the new fork, put on the handle bars, used the original bolt that holds it in.
6. So the fork is in place but the brake pads holder need 1/2 inch spacers between the fork and brake pad holder to locate the pads in center of the rotor. You need new bolts to hold it on.
    Luckily I had some bolts I could cut to fit (I'm a professional scrounger).
7. My brake cable fit. Someone in this feed said they had to buy a longer one.
8. I bought the fenders from Rad and had to really adjust the struts to get them to line up with the threads on the new fork. See my previous picture.
9. With a longer fork the center stand doesn't reach the floor. It needs to be 1 1/2 inches longer. After much thought, and without a welder, I decided to cut the center stand about in
    half. From a previous scrounge I luckily had stainless steel pipe that snuggly fit over the legs. I cut two pipes long enough to slide over the legs, adding 1 1/2 inch in length. four set
    screws keep it all together. The extra length makes the center stand stick out a little more, so far it isn't a problem. If they do drag sometime I may heat them up and squeeze them
    tighter.
I hope this helps.
Title: Re: Rad Runner Mods
Post by: Jman on October 06, 2020, 03:55:33 PM
Thank you Bob Mc, That will come in handy when I need to do that mod to mine!
Title: Re: Rad Runner Mods
Post by: dan26ntn on October 06, 2020, 09:41:48 PM
I've been looking around for a bit , trying to pin down a well made suspension fork for the RadRunner , and I did see the Bolton fork, but there is also an RST Guide 20 . Is there a reason that one wouldn't fit? I believe Bitrix sells them at around $250 USD  and https://classic-cycle.com/all/3064/204-suspension-fork-rst-guide-20-zoll-tnl-fatbike-1-1/8-ahead-for-disc-brake  . I don't know enough about the different details to know if it would be a better quality and fit than Boltons option.
Title: Re: Rad Runner Mods
Post by: wkindred on October 07, 2020, 10:44:55 AM
Quote from: dan26ntn on October 06, 2020, 09:41:48 PM
I've been looking around for a bit , trying to pin down a well made suspension fork for the RadRunner , and I did see the Bolton fork, but there is also an RST Guide 20 . Is there a reason that one wouldn't fit? I believe Bitrix sells them at around $250 USD  and https://classic-cycle.com/all/3064/204-suspension-fork-rst-guide-20-zoll-tnl-fatbike-1-1/8-ahead-for-disc-brake  . I don't know enough about the different details to know if it would be a better quality and fit than Boltons option.

hmmmm...specs make it appear to be a good and viable option -

Steerer length: 260 mm

Steerer diameter / stem width: 28,6 mm

Steerer daiemeter at cone seat: 30 mm

Installation hight: 420 mm

For Hub width: 135 mm

Travel: 45 mm

Ssytem: Coil in left stanchion

Damping: Oil in right stanchion
Title: Re: Rad Runner Mods
Post by: dan26ntn on October 07, 2020, 04:16:06 PM
Quote from: wkindred on October 07, 2020, 10:44:55 AM
Quote from: dan26ntn on October 06, 2020, 09:41:48 PM
I've been looking around for a bit , trying to pin down a well made suspension fork for the RadRunner , and I did see the Bolton fork, but there is also an RST Guide 20 . Is there a reason that one wouldn't fit? I believe Bitrix sells them at around $250 USD  and https://classic-cycle.com/all/3064/204-suspension-fork-rst-guide-20-zoll-tnl-fatbike-1-1/8-ahead-for-disc-brake  . I don't know enough about the different details to know if it would be a better quality and fit than Boltons option.

hmmmm...specs make it appear to be a good and viable option -

Steerer length: 260 mm

Steerer diameter / stem width: 28,6 mm

Steerer daiemeter at cone seat: 30 mm

Installation hight: 420 mm

For Hub width: 135 mm

Travel: 45 mm

Ssytem: Coil in left stanchion

Damping: Oil in right stanchion


When they say, "installation height" ; is that referring to the crown to axle measurement that Bolton states on theirs? If so, the RST looks to be a bit shorter, which may solve that kickstand and short people problem .
Title: Re: Rad Runner Mods
Post by: 992023515 on October 07, 2020, 05:51:05 PM
I like the custom seat. The front wheel seems a bit farther forward though and the handle bars seem lower. The front wheel looks to be 4 inches out from the frame where the regular fork holds the wheel about an inch away. Does that affect the ride?
Title: Re: Rad Runner Mods
Post by: Count on October 08, 2020, 11:26:52 AM
Nice job.  Looks just like mine. Your process was very similar to mine.  I like the look of your brass spacers; I used stainless.  My fender was installed when I bought the bike, and it was apparently installed backwards.  With the struts in front, I also had to do a bit of fabrication and bending, and ultimately used the axle as a mounting point for the strut.  I did need to make a longer axle, but that was a breeze with a piece of Stainless threaded rod, BUT I like yours much better!  Frankly, it was an easy job, and I did not need to modify anything on the bike frame, no drilling needed!  However, again, I like and recommend using the strut mounts on the rear of the fork legs like you did!

Quote from: Bob Mc on October 05, 2020, 08:31:07 PM
Howdy, I just installed the Bolton forks also. I used 1/2 inch brass spacers. So far the brakes work well. The forks are fantastic, compare a Jeep to a limo on a washboard gravel road. The fender struts required a lot of bending to fit to the fork holes.
Title: Re: Rad Runner Mods
Post by: dan26ntn on October 08, 2020, 12:09:34 PM
Quote from: Bob Mc on October 05, 2020, 08:31:07 PM
Howdy, I just installed the Bolton forks also. I used 1/2 inch brass spacers. So far the brakes work well. The forks are fantastic, compare a Jeep to a limo on a washboard gravel road. The fender struts required a lot of bending to fit to the fork holes.

Do you have any other pics of your installation? A bit further away to show the overall front end profile?
Title: Re: Rad Runner Mods
Post by: wkindred on October 08, 2020, 12:15:05 PM
Quote from: wkindred on October 07, 2020, 10:44:55 AM
Quote from: dan26ntn on October 06, 2020, 09:41:48 PM
I've been looking around for a bit , trying to pin down a well made suspension fork for the RadRunner , and I did see the Bolton fork, but there is also an RST Guide 20 . Is there a reason that one wouldn't fit? I believe Bitrix sells them at around $250 USD  and https://classic-cycle.com/all/3064/204-suspension-fork-rst-guide-20-zoll-tnl-fatbike-1-1/8-ahead-for-disc-brake  . I don't know enough about the different details to know if it would be a better quality and fit than Boltons option.

hmmmm...specs make it appear to be a good and viable option -

Steerer length: 260 mm

Steerer diameter / stem width: 28,6 mm

Steerer daiemeter at cone seat: 30 mm

Installation hight: 420 mm

For Hub width: 135 mm

Travel: 45 mm

Ssytem: Coil in left stanchion

Damping: Oil in right stanchion


the only issue i see with using this fork on the radrunner 1 is that there is no accommodation for fender mounts...
Title: Re: Rad Runner Mods
Post by: dan26ntn on October 08, 2020, 03:06:57 PM
 I believe the fender mounts just like it does on the Radrunner Plus, which is on the very bottom of the lowers and it's drilled for the top mount (of the fender) as well. Also  , I think Radpower's explanation of why they won't offer the RR+fork separately for the older RR1 customers is a bunch of bull. How in the world is the tire going to hit the frame? It's not like they HAVE to sell us anything, but for people that bought one before the RR+ was available; it'd be nice to have that upgrade. https://www.biktrix.com/products/rst-guide-fork
Title: Re: Rad Runner Mods
Post by: Count on October 08, 2020, 04:22:57 PM
The fender mounting does present a minor obstacle, but frankly 30 minutes with a couple of pliers, and some trial and error bending the struts, and the fender can be mounted up nicely.  Bob Mc and I both got our fenders mounted cleanly, in 2 different ways.  I actually like his better, but fender mounting is not even close to an insurmountable issue! 

Quote from: dan26ntn on October 08, 2020, 03:06:57 PM
I believe the fender mounts just like it does on the Radrunner Plus, which is on the very bottom of the lowers and it's drilled for the top mount (of the fender) as well. Also  , I think Radpower's explanation of why they won't offer the RR+fork separately for the older RR1 customers is a bunch of bull. How in the world is the tire going to hit the frame? It's not like they HAVE to sell us anything, but for people that bought one before the RR+ was available; it'd be nice to have that upgrade. https://www.biktrix.com/products/rst-guide-fork
Title: Re: Rad Runner Mods
Post by: Count on October 08, 2020, 04:29:55 PM
Just wait until you devise some sort of seat suspension, and you will REALLY feel like you are in a limo!  I observed the same center stand issue as you did after the front end installation, but failed to equate it to the new front fork installation!  I thought I had somehow done some damage to the stand legs, and have been trying to devise a way to correct the issue.  I'll post back if and when I come up with something!

Quote from: Bob Mc on October 05, 2020, 08:31:07 PM
Howdy, I just installed the Bolton forks also. I used 1/2 inch brass spacers. So far the brakes work well. The forks are fantastic, compare a Jeep to a limo on a washboard gravel road. The fender struts required a lot of bending to fit to the fork holes.
Title: Re: Rad Runner Mods
Post by: mbates50 on February 01, 2021, 04:56:06 PM
Which bike did you install the Bolton 35 amp controller? Their website sounds kinda iffy with the Rad City
Title: Re: Rad Runner Mods
Post by: Zbugsii on February 04, 2021, 06:12:30 PM
New storage and large crate for carrying stuff and groceries
Title: Re: Rad Runner Mods
Post by: Kevin Turtle on March 01, 2021, 11:33:04 AM
Added rear signal lights with laser lane markers, seat, accessory bar on handlebars where I mount my dji mavic air 2 controller, horn, bolton controller and display upgrade just cleared customs, next up will be fatty slicks. Also added some skull decals on battery and center console and white spoke sleeves. Future also will have upgraded battery and add front suspension
Title: Re: Rad Runner Mods
Post by: Altema on March 02, 2021, 05:42:20 AM
Quote from: Kevin Turtle on March 01, 2021, 11:33:04 AM
Added rear signal lights with laser lane markers, seat, accessory bar on handlebars where I mount my dji mavic air 2 controller, horn, bolton controller and display upgrade just cleared customs, next up will be fatty slicks. Also added some skull decals on battery and center console and white spoke sleeves. Future also will have upgraded battery and add front suspension
Nice setup! Is that a custom trailer, and what's it like pulling it?
Title: Re: Rad Runner Mods
Post by: Hbomb on June 13, 2021, 07:59:38 AM
Count wrote:

" A Bolton suspension front end, 35 amp controller (mounted exactly where the original mounts, in a waterproof enclosure); A new TRUE 1000w Baffang motor (which makes a HUGE difference in power)...."

Hi count please let me know how the install of the 1000w motor went for you with the cable exit being on the brake side. I am in the market for a 750 watt with the correct cable exit, but can only find 1000 watt on Ali Express website. Thanks! -Heidi

Title: Re: Rad Runner Mods
Post by: LargeBlueSpruce on September 28, 2023, 09:55:32 AM
I'm in the process of removing the Bolton (Area 13 shock).  The installation went fine.  I had to install the spacers for the brakes and longer screws, but no big deal. 

The issue I'm having is something about the bikes geometry is off and the turning is very squirrely (can't ride with no hands).  I've adjusted the handle bars several times, but it just doesn't feel right. Area 13 has agreed to accept my return and I've informed them I don't believe this shock fits the Rad Runner II properly.

I'm surprised you like the Bolton Shock on your Rad Runner II.  I've found it to be unrideable.  Anyone else have the same experience?  I'd love to find an option that maintains the same geometry.  Thanks
Title: Re: Rad Runner Mods
Post by: handlebar on September 29, 2023, 05:25:32 AM
The problem is so common among modern bikes that I've seen videos where experts say you need to practice taking one hand off the bar on a deserted road so that if you need to take your hand off the bar to signal or for some other reason, you wouldn't crash.

It was so severe with my Radrunner 1 that until I modified it, I had tennis elbow from trying to control it when I had to take one hand off the bar to signal. The biggest problem was the seat position. The pavement around here is rough, so I needed to stabilize my upper body. With only one hand on the bars, it took tremendous torsion on my elbow to brace myself while keeping the bar straight. It wasn't safe.

Moving the seat back several inches fixed that. Now I could brace with my feet against the pedals, making control with one hand easy and safer. I could even ride with no hands, but I didn't like it. There were other problems.

When a bike tips, the contact patch tire of the tire moves to that side of the tire's centerline, and that pulls the bars to that side. With no hands, that could cause a crash if it pulled the handlebars too far. Trail counteracts that tendency. My Radrunner has 6 cm of trail. That would be fine for a tire an inch wide, the Radrunner tires are 3.3 inches wide. I think more trail would make it safer.

Then there's head angle, the angle of the steering axis from horizontal. The farther it is from 90 degrees, the more turning the handlebars moves the contact patch in that direction, with respect to the rider more than with respect to the tire's centerline. Leaning with no hands can cause the contact patch to move just far enough to bring the bike vertical and return the steering to it's original direction. It's a sort of autopilot.

My Radrunner 1 has a 70 degree steering head angle. There's not much autopilot effect, and if it started to turn sharply I'd need to grab the bars fast, not only to steer but to stabilize myself. For some reason, steering heads these days are often even steeper.

I grew up with English bikes having a 66-degree head angle. Turning required a bit of countersteering to get the contact patches out from under me so I could lean. On the way back from the municipal pool I'd come down a side street with a grade of about 20%. On a bicycle, that seemed a bit like freefall. The stop sign at the bottom required heavy use of the brakes. They were rim calipers, so cooling was excellent. It would have been dangerous with a coaster brake.

I used to spare my brakes by grabbing two corners of my towel with each hand and holding it behind my head like the parachute on a dragster. When it opened at that speed, it would jerk me. The bike would continue straight until I provided handlebar input. It was a far more effective air brake than initially expected. I needed only a little use of the calipers as I approached the stop sign.

I think head angle is the most import factor in hands-free riding, but changing forks would not have changed your head angle. Your front tire may look well inflated, but I think its pressure is lower than when you used to ride hands free. With less pressure, the contact patch on that fat tire would move farther from side to side as the bike tipped, and that would pull the handlebars in that direction. As you say, squirrely.