What is the RC story behind Rear Toe-In?

[TokyoProf]

What was the first RC buggy to include rear toe-in as part of its mechanical design?
Was the Yokomo 834B the only RC buggy to have won without any rear toe-in?
Did Gil Losi Jr. ever think about implementing it into his 4WD at the 1985 IFMAR worlds? He must have known some of the tuning benefits of toe-in at that time...

On a side note, as a kid I always fantasized about implementing toe-in into my hopeless Tamiya vintage cars...I always believed THAT was the reason I failed to compete with my Vanquish, Egress, Thundershot, etc.

[coxbros1]

What was the first RC buggy to include rear toe-in as part of its mechanical design?
Was the Yokomo 834B the only RC buggy to have won without any rear toe-in?
Did Gil Losi Jr. ever think about implementing it into his 4WD at the 1985 IFMAR worlds? He must have known some of the tuning benefits of toe-in at that time...

On a side note, as a kid I always fantasized about implementing toe-in into my hopeless Tamiya vintage cars...I always believed THAT was the reason I failed to compete with my Vanquish, Egress, Thundershot, etc.

Thundershot suffered horribly from no rear toe!

[Saito]

The Boomerang (and hence the Bigwig and Super Sabre and possibly HS2, I would assume since they share the same rear suspension design on the Hotshot series) are rumored to have a degree of rear toe over the Hotshot/Supershot.

The Thundershot series oversteers from several choices made in its design, including the lack of rear toe, from recent research I did into that buggy family. However, the rear arm mount has 2 sets of holes. The manual instructs the builder to assemble it with the holes in line with the front rear arm mount points, thus, no rear toe. The rear arm mount can be flipped and mounted upside down. This second set of holes (spaced wider than the front rear arm mount holes) provides rear toe.

The Avante, in theory, could possibly have rear toe adjustment but in reality not much could be done before the rear dogbones would fall out. The other cars in the Avante family ditched the "adjustable" rear trailing links for a solid nylon trailing arm for simplicity/durability/reduced weight.

[1911Colt]

I always found it interesting that the early CATs (SWB, XL, XLS) had adjustable links for rear toe, but no adjustable links for front or rear camber. In retrospect, they were probably right.

[Saito]

I found that interesting to about early CATs too. Same with the front of the AYK Pro Radiant.

There is much about the Avante suspension/steering design and geometry that is puzzling. Rear toe might have calmed some that platform's nervous handling. Why did the Avante series have no kick-up with only 10 degrees of caster built into the uprights? Why the tremendous scrub radius? I'd really like to know where designers were going with those cars as earlier Tamiya efforts in 4wd did not have those issues to that degree. It then seems every effort made from Avante to Egress and finally to Jamie Booth Egress was an attempt at un-doing all those odd design choices to bring it more in line with what traditionally worked.

[RCveteran]

To throw a rant in, the evolution to "what works" though is how you end up with a bunch of race cars today that are all virtually identical. There is a fastest way for sure but not necessarily the most interesting way when it comes to design.

[Saito]

Totally agree. Things are fairly boring today compared to the interesting ideas and concepts of yesteryear. Its one of the reasons I'll always be faithful to Tamiya. They still do some things differently.

[1911Colt]

To throw a rant in, the evolution to "what works" though is how you end up with a bunch of race cars today that are all virtually identical. There is a fastest way for sure but not necessarily the most interesting way when it comes to design.

Convergence of design is both inevitable and boooooring.

[XLR8]

I found that interesting to about early CATs too. Same with the front of the AYK Pro Radiant.

There is much about the Avante suspension/steering design and geometry that is puzzling. Rear toe might have calmed some that platform's nervous handling. Why did the Avante series have no kick-up with only 10 degrees of caster built into the uprights? Why the tremendous scrub radius? I'd really like to know where designers were going with those cars as earlier Tamiya efforts in 4wd did not have those issues to that degree. It then seems every effort made from Avante to Egress and finally to Jamie Booth Egress was an attempt at un-doing all those odd design choices to bring it more in line with what traditionally worked.

The answer is simple; Tamiya RC's are designed to be fun to build and set pretty on the self, not to be competitive on a track. They are essentially highly detailed static models that can be driven remotely.
Okay seriously, I really like all my Tamiya RC's (my first RC car was a Sand Scorcher circa 1979). It's when I actually drive them that I begin to question why I own such a poor performing car.

[RCveteran]

Convergence of design is both inevitable and boooooring.

Also seems to impact vintage races. Once you are on a smooth clay or carpet track there is a "best" vintage option. Everything else doesn't work well so the Scorpions and such stay home unfortunately. I don't understand them as I do not speak Japanese but the videos in Japan seem to show more vintage get together where you appreciate running them for what they are, Tamiya included. Watched Akira Kogowa (Kyosh Ultima Designer) running a Grasshopper recently with a group of folks on an outdoor track that reminded me of being a kid again.

https://www.youtube.com/watch?v=oc-FubNiCvA&t=439s

So yeah, back to toe in, I love my Tomahawk for it, it changes so much as you compress the suspension it's like having constantly adjustable toe in

[Frankentruck]

The answer is simple; Tamiya RC's are designed to be fun to build and set pretty on the self, not to be competitive on a track. They are essentially highly detailed static models that can be driven remotely.
Okay seriously, I really like all my Tamiya RC's (my first RC car was a Sand Scorcher circa 1979). It's when I actually drive them that I begin to question why I own such a poor performing car.

My #1 rant with Tamiya is that the steering capability is typically garbage by design. Off center steering horns and unequal length tie rods seem like they are a top design requirement. Please Tamiya, how about the same turning radius in both directions?

[XLR8]

The answer is simple; Tamiya RC's are designed to be fun to build and set pretty on the self, not to be competitive on a track. They are essentially highly detailed static models that can be driven remotely.
Okay seriously, I really like all my Tamiya RC's (my first RC car was a Sand Scorcher circa 1979). It's when I actually drive them that I begin to question why I own such a poor performing car.

My #1 rant with Tamiya is that the steering capability is typically garbage by design. Off center steering horns and unequal length tie rods seem like they are a top design requirement. Please Tamiya, how about the same turning radius in both directions?

Yes, massive bump steer, etc.
However, the new BBX is actually a well designed buggy - which also happens to have a crazy amount of rear toe angle.
Mine is still setting pretty on the shelf but I really need to get it down and drive it. I think it will handle quite well - for a Tamiya.
Getting back to the OP's question, what is the very first RC buggy? Is it the Rough Rider or something else? SRB's had zero rear toe angle. Did RC buggies even exist prior to 1979?

[GoMachV]

Why didn't the B6 have kpi adjustable steering? Why wasn't the b4 a mid motor? Why didn't the rc10 have long front arms.

Because at the time, those things were either not thought of yet or deemed important

[RogueIV]

Why didn't the B6 have kpi adjustable steering? Why wasn't the b4 a mid motor? Why didn't the rc10 have long front arms.

Because at the time, those things were either not thought of yet or deemed important

And tracks have changed considerably since then as well. Almost all current tracks are super smooth and high grip. There's no more loamy or bumpy tracks, sadly. While I do enjoy carpet racing racing on dirt back in the day was more of an adventure, conditions could change drastically as the day progressed and winners were those who could adapt quickly to the changes. Now most dirt tracks are super well groomed to the point where people are using slicks. Speeds have increased greatly so jumps are larger now.

The cars have adapted to these modern tracks and conditions, but I dare say they might struggle if they were on an older style loose and bumpy tracks, getting dirt in all those close tolerances. It would be interesting to see comparisons of modern and older buggies all with proper setups on multiple tracks old school style and modern.

I also will say, it's very easy to "get lost in the sauce" with modern buggies with the 100s of setup options they have compared to older cars that only had a few things to adjust, aside from making your own parts.
"Make the suspension adjustable and they will adjust it wrong" -Colin Chapman

[GoMachV]

When we started racing no prep 4 or so years back, mid motor cars didn't work at all. Way too finicky. In a year and a half everything competitive was mid motor. The tires unlocked the mid motor stuff. Belted and sauced to the moon. It's kinda funny as it isn't far from what happened with early loamy off road tracks and modern sugar tracks it just happened really fast.