Kyosho Optima - A trip back in time with SVT

[svt923]

Greetings from the past!

Yes gentle reader, I, much like Tony Stark in Avengers Endgame, have figured out time travel. Did I just give away a major plot point from the movie? You bet I did and it's been 2 weeks so that is more of a you problem.

Anyway, time travel affords me so many opportunities: gambling for personal enrichment, assassinating Hitler, or the Futurama option.



But what we all would do is bring back cool RCs from the past! That is what we would do, right?

It is already in the thread title so lets get to it.



Snake is impressed because he is old and old people are easily impressed by things from earlier in their lives. Give someone in their 80s a rotary phone and they will stare at it like its the Sistine Chapel.

There has been a retro buggy resurgence going on in my area. While I'm normally one to jump into any questionably feasible RC trend, the retro buggy one wasn't that appealing for whatever reason. After much persuading effort from a buddy, I gave in since there will be retro buggy racing at an event here in the fall. When the Optima rerelease happened a few years ago, I thought it was a very well executed rerelease (compared to Tamiya) and it would be cool to have one but never followed through on it. Since I now needed a retro buggy, the Optima seemed like the natural choice.

I don't really remember the Optima from my early days of RC because:

#1 - Kyosho was this fancy, exotic brand of race car that was hard to find.
#2 - Any Kyosho race buggy would have far exceeded my RC budget at the time thus defeating all desire to learn about them.
#3 (the actual and most important reason) - I'm just not that old.

Enjoy these pics of the gloriously retro packaging while I respond to some angry letters from the AARP.




Companies really don't spend enough time on packaging anymore. Everyone lost their minds over the VS4-10 packaging while Kyosho and Tamiya were knocking that style out in the mid 80s. More kits should present the fanciest parts on a top tray like a charcuterie board.

The body was also sitting on top of the box.



It is kinda amazing that these Kyosho buggies wouldn't have looked out of place with the buggies of 20 years later.

Are there stickers?



Oh boy, are there stickers! Roughly 8,000 of them by my count and Kyosho has the decency to die cut them for you (ahem Tamiya).

Snake doesn't do much around the shop anymore but he couldn't resist checking out the tires.



Kyosho says these are a "new, softer compound" which means the original Optima tires must have had all the softness of a skateboard wheel. These aren't terrible, kinda feels like an Axial RTR tire.

Snake was exhausted from rolling the tires a few feet so he put on some golf and took a nap. I powered through the unboxing and found some less than stellar packaging.



The tire foams were shoved in the box much like how everyone puts things in a garbage can when they don't want to be the one to take out the trash. Gonna have to give these a couple days to come back into shape.

Alright, time to get building.



Bag A seems like a good place to start.

I have been told these kits go together really fast.



Whoa, I only installed like 6 screws.

The original Optima was chain drive but the rerelease has the option of belt drive. I went belt drive because it is quieter, smoother, and, most importantly, handles more power. This will be vital to future stupidity.

Belt tunnels added.



Sealed for my protection.

Chassis time.



Just like an aluminum chassis on a new 4wd buggy!

Bolting the drivetrain to the chassis and things start coming together quickly.



The front gearbox has a nicely contoured skidplate protecting everything.



Its really tucked in there but the steering bellcranks with an integrated servo saver have been installed. A lot of retro buggies have awful steering but this setup feels super smooth so far.



Seriously, how do you even tell these buggies apart?





Uncanny.

That is about all from me for now. More, likely SMH inducing, updates to come.

[soze]

THe Kyosho legends series is absolutely nostalgia fantastic. I'm waiting for the right time to build mine as these are all shelf queens for me and I have no space currently. I need to pick up the recently released Turbo Optima.

[B-MOW71]

I'm so glad you purchased this and are making a build thread about this amazing car from the past. It is already bringing back some great memories for me. My very first "real" offroad racing machine was the Turbo Optima that I bought back in 1988. At that time it was the king of the local tracks that I used to race on.

I'm glad to see that they offer the belt drive now. Mine originally came with the chain drive. It worked ok, but was very noisy. Also, the addition of foams in the kit seems odd to me, but glad they did add them with the softer tires. Back in the day when I had mine I don't believe foams even existed! Or at least nobody in my area ever ran them. The tires were hard as bricks and didn't require the foams.

I'm really looking forward to following along with your build. Thanks for sharing with us!

[svt923]

Originally Posted by soze

THe Kyosho legends series is absolutely nostalgia fantastic. I'm waiting for the right time to build mine as these are all shelf queens for me and I have no space currently. I need to pick up the recently released Turbo Optima.

I was too impatient for the Turbo Optima and ordered this about 3 weeks before the Turbo version hit stores.

This was the other retro Kyosho project I had on the bench:



My buddy's Beetle had a problem popping driveshafts so I made them longer to stay in the drive cup.



This got taken apart so many times and some aspects of the design are comically bad but a stupid kind of fun washes over you when building. I was dumb for not getting one sooner.

Originally Posted by B-MOW71

I'm so glad you purchased this and are making a build thread about this amazing car from the past. It is already bringing back some great memories for me. My very first "real" offroad racing machine was the Turbo Optima that I bought back in 1988. At that time it was the king of the local tracks that I used to race on.

I'm glad to see that they offer the belt drive now. Mine originally came with the chain drive. It worked ok, but was very noisy. Also, the addition of foams in the kit seems odd to me, but glad they did add them with the softer tires. Back in the day when I had mine I don't believe foams even existed! Or at least nobody in my area ever ran them. The tires were hard as bricks and didn't require the foams.

I'm really looking forward to following along with your build. Thanks for sharing with us!

Belt drive, full hex hardware, 48P gears, and the softer tires are the major improvements, probably some other small things that an Optima aficionado would notice as well. All things that don't take away from the original design but make it worlds better.

The electronics, on the other hand, will be far and away from what would have been run in the 80s.

[DukeMinnix]

Cool buggy. Putting pictures to what words you told me about. Nice.

[svt923]

Originally Posted by DukeMinnix

Cool buggy. Putting pictures to what words you told me about. Nice.

Indeed, pictures make the internet better.

Speaking of pictures, I have a few more.



Suspension arms have been added. The hinge pins are secured by setscrews in the arm mounts. Why did the industry ever move to e-clips on hinge pins only to move back to clipless designs? It is one of the great mysteries of RC.

Things slowed down over the bit of time I had to work on this last night, mostly because it required building turnbuckles at this point. Building turnbuckles sucks, this is an indisputable fact, but putting rod ends on a hunk of threaded rod and needing them to be matching lengths is even worse. The lack of actual turnbuckles may be the worst part of retro cars.

The shock towers were installed as well.



Installing these 2 screws holding on the rear tower made me grateful this version has hex hardware and shed a tear for those who had to assemble these with phillips screws back in the day. You can't really get your driver exactly perpendicular to the screw so you're trying to tighten them at an angle while threading into some tough plastic. I assume you threw out these screws and replaced them with new ones every time the shock tower was removed on the original version.

Driveshafts, steering, and rear end components installed.



The kit makes use of a few different types of plastic. The c-hubs and rear hubs are molded in a much stiffer plastic than the gearboxes.

This is also where the 1 aftermarket part in this build comes into play.



These CVDs are from one of those brands you get from RC Mart (Xtra Speed? Yeah Racing? I don't really remember). They seem nicely made, have little slop, and will keep me from losing front dogbones after they get ejected in a crash. Also, they were $20 while Kyosho universals are like $50 so there may be a small (large) component of me being cheap.



Metal knuckles are a nice touch, whatever they are made from will obviously hold up better than plastic. I believe the 12 mm aluminum hexes with captured screw pins are a modern upgrade to the original. Not exactly sure because, again, I'm not that old.

Standard buggy stuff out back.



The rear hubs have inserts to adjust rear toe but I went with the kit settings. I'll assume that I won't be good enough at driving this thing to tell the difference between 2* of rear toe and 2.5*. Standard issue dogbones are sending the power to the rear wheels, there is less of a chance these will pop out than the ones on the front end.

Top deck is now on.



The upper deck serves as the electroncs mounting area and seals off the rest of the top belt channel. The 2 wings coming off the deck are the battery mounts, there is an additional set of holes further in for mounting 2S hardcase shorty packs. I'm still having the internal debate if a full size or shorty pack is the way to go.

Anyone notice that little body post on the top deck? That is where the interior mounts. I love the small commitment to realism of the classic buggies.

One last cool bit of old tech to note.



See those slotted screw holes? There are 8 of them on the front end. That is how belt/chain tension is adjusted which is needlessly complicated. I love it.

Hopefully this fulfills your need for old Kyosho building for the day because that's all I got. A new ESC will have to be ordered because the one I planned on using is too big then comes awful steps like building shocks, cutting the body, and gluing tires. Updates will come when those tasks become the least objectionable things I have to do in my life.

[B-MOW71]

Glad to see Kyosho ditched the dreaded phillips head screws and went with hex head. They were a PITA. I have stripped many of the heads out. I'm not sure why I never thought about switching out the screws.

You know, I can't remember if mine had wheel hexes or just pins in the axles. it's been way to many years ago to remember, but I'm thinking they were pins like my AE Team Associated RC-10 had. It's also nice to see metal knuckles too.

Yep, I got my daily dose of Kyosho! I'm good till the next!

[Sydwaiz]

That's really cool! I kinda want one now.
Around that time, I had a Tamiya Falcon and my dad built a car that might have been a Kyosho Optima. I definitely remember the chain drive. I want to say the body was more rounded though so it may have been a different brand or it could just be my memory. I can't remember what other brands there were back then.

Edit to add: I just did some googling and found it! It wasn't an Optima but a clone. A Great Vigor Beagle sold by Ascot. Now it makes sense because I'm from the area and my dad's machine shop was in Gardena as well! (For those that don't know, Ascot was the local dirt track for sprint cars. I miss that place.)
I think I'm still going to buy one of these Optimas though!

[SIK_BOY]

Awesome build sir! always refreshing to break away from social media and come back to this forum, and today i stumbled into your thread! Thanks for sharing!

[svt923]

Originally Posted by Sydwaiz

I think I'm still going to buy one of these Optimas though!

The time is at hand to purchase all things of the ye olde variety!

And the Turbo Optima just hit stores which is 150% more gold than this version.

Originally Posted by SIK_BOY

Awesome build sir! always refreshing to break away from social media and come back to this forum, and today i stumbled into your thread! Thanks for sharing!

Is it too perfect to launch into an "old man yelling at kids and their social media" rant in an old car build thread?

Yes, it is so that won't be happening. Things are definitely better here.

Originally Posted by B-MOW71

Yep, I got my daily dose of Kyosho! I'm good till the next!

Then allow me to administer the next dose.

We left off with me needing to work on some of the worst RC tasks in the world. Using the book of suggestions, aka the instruction manual, the shocks were chosen as the first circle of RC hell.



These are probably exactly the same shocks you may remember from the Optima of yesteryear; red aluminum bodies, bottom loaded seal cartridge, spiffy red plastic pieces. One of the weird quirks of the design is there really isn't anything holding the o-rings in the cartridge. I guess there is kinda a groove in the bottom cap that holds them in but nothing really secure. Strange but I guess it works.

The suggestion of the manual for the pistons and oil were small 2 hole pistons with 7.5wt oil. Small diameter hole pistons and oil with all the consistency of water seems like a strange combination. In an effort to move to a more modern sounding shock setup, I went with 3 hole pistons in the rear and the larger 2 hole pistons in the front with Losi 20wt oil all around. Is this optimal? No idea but it feels pretty good on the bench.

Shocks installed in their one and only location.



This part of the build is just like a choose your adventure book.

For a big ass, old style bumper, turn to page 93
For a sleek, modern bumper, turn to page 127



Page 127 it is.

Time to start installing electronics. Steering servo is up first.



I chose this Spektrum 6070 servo out of my bin of electronics. It's fast and should have plenty of torque. Kinda strange making a build thread on here and saying 125 oz of torque is plenty.

One of thing I really like about this servo is it's low profile so the entirety of the servo fits within the width of the chassis.



Something about the though of a servo exposed on the bottom of the car just didn't seem like a great idea to me. No concern about that now.

Gears going in.



This is another delightfully old school bit of this car. While there are gear boxes, there isn't a whole lot going on inside other than the diffs. Almost all the gear reduction comes from these gears on the outside. A modern change to the original design is the spur is now 48P while I guess the original was likely a .06 mod.

Kinda like a Berg gearbox only different in design and function.



The manual says to grease the metal gears which I understand because they are transmission gears but dirt and grit will find their way into these external gears. I went with a dry chain lube to give the gears something that would lubricate and not attract dirt.

Speaking of dirt, the gear cover was installed at this point.



The cover includes a foam gasket to try and keep the dirt at bay. It is a nice touch.

So you have noticed there is a motor installed. Are you curious what motor will be powering this delightful bit of 20+ year old engineering?



To preemptively answer some questions you may have:

-Yes, that is a Holmes Trailmaster Pro 4500kv
-Yes, I realize this car was made for brushed motors
-Yes, I realize this is a terrible idea
-Conservatively, I estimate this will go 217 mph
-No, I'm not changing my mind.

Glad we are now on the same page.

While we are still on the subject of electronics, let me talk for a minute on ESC mounting. The designers at Kyosho expect you to stick your ESC to the underside of the top deck here:



This is objectively lame. The space available there is small and part of the chassis combined with the belt tunnel makes it even smaller. I don't know how anyone ever stuck the giant electrical bricks that were 80s ESCs to that space. Every racer must have ditched the driver figure to stick their Novak 410-M1s or Tekin 410Ks on top of the deck.

This is where we optimize for modern technology. New brushless ESCs are waaaaaay smaller but even still the logistics of mounting the ESC on the bottom of the deck are terrible and there is no way I'm not running the driver.

So, much like the Delorean in Back to the Future 3, a piece of technology not of this time comes to the rescue.



The magic parts making robot did my bidding after I designed this ESC mount. The new position offers more space for the footprint of the ESC and can be removed with 4 screws (after taking off the 6 in the top deck but details). The wires can now be routed up from ESC, which is their natural direction, and it is more protected within the chassis rails. Oh and I guess it lowers COG and centralizes weight balance because performance.

With the mangled tire foams regaining about 80% of their shape from sitting out for a week, I threw the tires and wheels together.



The wheels make you realize that companies don't try hard enough to make race buggies look good. Another possibility is what looks good has shifted so far that I no longer know what looks good. Maybe these should be replaced with a set of fluorescent yellow dish wheels.

And with a couple more lock nuts, we have a roller.



I may not know what type of surface I will be running this on but I can undoubtedly assure you that, between these tires and the motor, chunks of it will be flung everywhere.

So now I wait for the ESC to be delivered and then paint will be slung. I have a kinda ambitious paint job planned but we will have to see if that comes to pass.

End old Kyosho post.

[soze]

Nice update! I'll be adding the Turbo version to my collection soon.

[smokinapankake]

Love the Optima! Long live King Optima! To my eye it is far and away the coolest, best looking, and most realistic looking buggy of all time. I had one back in the day, outfitted with the Option House belt drive conversion, along with a full length undertray. As I recall it was rather fragile but the looks and the tech made up for it. The original did not use pins in the axles, rather, 12mm hexes which were a taper fit. You had to pop them off with a flat screwdriver. Effective but a pain, too. Wheels were a 3 piece design - no foams included or needed!

[alexleblanc]

i ordered one of these yesterday so i can build the one i have as a runner and the other as a shelf queen.