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The COX/Kyosho Scorpion had its peak on the track 83-85 until the RC10 hit the tracks! This will be an effort to build a 26 year old Turbo Scorpion racer with some hop-up parts from CRP + some others. You could say that the Scorpion was the first big electric racing buggy in US and Japan. When you start to race something, the third-party company’s starts to pup-up making aftermarket parts. Often they where racers themselves ho started companies, they saw a changes to sell their ides to other racers. I have done it myself; I think I sold about a 100 under trays to the Mid Optima (SWB) in Sweden alone.

The biggest problem when you start to renovate an old Circuit 1000 car is the aluminum chassis bars. Those are always bent one way or another… So a few months ago I got hold of brand new ones from a guy I Germany almost free. This will be my blueprint chassis bars for the future! You can bay repro from pargu2000 without ruin yourself, but original is still original!
When you straighten out the chassis bars, take your time so you don’t ruin them for god.

The two on the right is the new ones.

When you look upon a 2-3 year younger racecar they are almost clean from screw with button heads. But the Scorpion is full of them, but that problem is now taken care of with 9 countersunk screws. Can’t have button head screws underneath a racer!

Time for looking over the gearbox!
The earlier Scorpions had no differentials, just a plastic gear. I have some prototype metal gears from CRP. But at the same time Dirt Burners realest a ball diff to the Scorpion (if you have one for sale, please send me a PM). When the Turbo Scorpion was realist in 85 it had a gear diff installed, and you filled the gearbox with oil… I will use grease instead this time. I remember my sticky gearbox from way back, oil mixed with dirt… As usual when it comes to install gear diff, do not forget shims it rather tight if you want it to last.

Prototype metal gears from CRP

The motor plate on the Scorpion is no good for a racer, you have two alternatives! Low or high gear…

A few racers did their own modification, but CRP made a motor plate #1708 that allowed you to change the pinion. So this will be my choice for this racer…

On top is Kyosho Scorpion original motor plate

CRP has a bras outgoing gear #2108 that they still have for sale. But the Scorpion is made out of plastic, and it’s less mass to get in motion and therefore faster acceleration… my choice for the racer.

During the renovation of the gear box I replaced all metal brushing to ball bearings. I have to admit that I chose the cheapest set, $15 shipped to Sweden. I have been waiting for Avid RC Revolution bearings, but they are still out of stock.

The Kyosho Scorpion have trailing rear arms, they is mounted on two aluminum plates. Do to the problem with lost dog bones, the Turbo Scorpion got one aluminum plate instead of two together with Assault and the Advance buggies. In order to adjust to in and to out I chose CRP’s #1024 in fiberglass (still for sale). And I used CRP’s trailing arm pivot #1701, instead of the original in aluminum. Maybe not the right chose for a racer, but I’m a sucker for aperients sometimes…

To cope with the lost dog bones I have chosen the rare CVD’s from CRP #1706. Another way to prevent the dog bones to fall out is to mount a few mm of silicon tubing on each side of the dog bone too keep it centered.
To be continued!

wow this is gonna be a nice build! I'm a sucker for scorpion series myself.Can't wait to see your finished product I'm still missing a Turbo Scorpion in my collection The gearbox is very loud, for some unknown reason my tomahawk's differential gear is a little bend making it even louder

Hey Lars, I'm looking forward to seeing this one. Are either of the parts I sent you going into it?

sgirouard wrote:Hey Lars, I'm looking forward to seeing this one. Are either of the parts I sent you going into it?

No, not in this project, I used those from CRP.

kaz_z wrote:wow this is gonna be a nice build! I'm a sucker for scorpion series myself.Can't wait to see your finished product I'm still missing a Turbo Scorpion in my collection The gearbox is very loud, for some unknown reason my tomahawk's differential gear is a little bend making it even louder

Who isn’t …
I think something is bent, maybe the out drive

Awesome Stuff.

I wish i could embark on such a rare project. Your dedication to this is 150%.

Keep the pic's coming.

Mad Racer wrote:Awesome Stuff.

I wish i could embark on such a rare project. Your dedication to this is 150%.

Keep the pic's coming.

Thanks!

Okay...

Time for the front:
I have used CRP’s front arm shaft #1707 (still for sale) that are 8mm wider than the original shaft. This gives me a change to widen the front if I want to. This shaft is bit sensitive for crashes and big jumps, it tend to twist. To prevent this I drilled two holes in the arm shaft blocks that I thread for set screws in an attempt to keep in place. Live test later on will give me the answer if I have succeeded…

In my look for hop-up I came across a rare CRP part, at least it’s what I think. It’s a sway bar NIP (#1703) to my racer; I had only seen a bad picture of it before. This is a simple construction! The sway bar runs through a bras tube, the ends attaches with straps to the front trailing arms. But I think it will do the job!

To protect the sensitive Scorpion front I chosen a Pro-Line bumper made for the Scorpion and the RC10 #4504. Pro-Lines bumper cover the whole front and is much more absorbent then the original Kyosho bumper.
The dampers are relay important; my intention was to find some nice aftermarket ones. But I don’t know what aftermarket dampers there where at that time (-85) except for RC10 shocks. So I would be grateful for any input in this subject!

In the meantime I have (cheated) chosen a modern aftermarket damper from Yeah Racing. They have an 11.8mm damper in various lengths, so I chose 60mm for the front and 70mm to the rear. Scorpion’s damper is 10mm in diameter, so no modification was needed on the shock towers. But I couldn’t help myself; I have to make a new rear tower… I made it about 10mm taller and drilled two extra holes. This will gives me a little to play with… and I might make one for the front later on.

Time for the white Turbo Scorpion tube to be mounted, but this it’s not an original tube. I came across a guy I Germany that was working with laser sintering technique (http://en.wikipedia.org/wiki/Selective_laser_sintering). He had made a few repro tubes and he has made some modifications. The best feature is that you can screw down the steering servo; a thing Kyosho engineers should have done 30 years ago.

Marwan is the supplier of the Turbo Scorpion body; he has a great combo deal, body, wing and decals! And all of you that have dealt with Marwan know that he has gate repro stuff.
Now I’m at that point that I never got the hang of, painting a lexan body! I can cope with one color, but when its two colors it starts to get complicated, and I was thinking of using three colors… Historically I have always left that part to guys knowing what they are doing! 20 years ago I even purchased an air-brush, but I never get around to opening it. And now I don’t even know where it is…

But what the heck, I will give it a try. I went down to my local hobby store and purchase three rattle-cans! My intention was to paint a box-art body, blue, white and red. White and red no problem, but the blue color I ended up with was Renault Alpina blue. What do you think guys, not bad for a novice?

After market body’s for the Scorpion is wary rare and hard to find. A few months ago I spotted a NIP McAllister body to the Scorpion on the bay. I decided to buy it to any cost; I set my top bid to $260… yes you read it right! I was in the lead with $125 until it was 5 seconds left, and yes I ended up as the first looser… The next day I contacted McAllister asking if they still have that mould, but no…

The reasoned I wanted that body is to get rid of the cage and aluminum roof. I think I will make my own mould and design next winter!

To be continued!

That scorpion is going to turn out quite nicely. I too started to do a racer build on one but ended up abandoning the project when I couldn't get all the after market parts to work in conjunction with each other.

I can't believe the value on that body. I bought one years ago and decided against it when I found two NIP stock body. Looks like it time to start offloading scorpion parts.

Stock cars are cool, but a race car build up is always exciting. Take some video when you run it!!

If you thought that I ran out of CRP pats you where mistaking! This 6” wide CRP wing is an adjustable ”Aero-Thch Tri-Level Wing” (#6001). Maybe more suitable for on-road cars than off-road cars. But racers especially back then tested every ting just to get an edge over the competition. The wing is rely advanced, it will probably take days to sort this wing out alone. So I reckon that I will end up with regular wing in the end.

Now I get to a difficult part for a 26 year old runner/racer, the tires! The Scorpion rims are 1.5” at the rear and 1.9” at the front. To find new tires could cost you a fortune and some time to find. And if you find some tires, they hard as “hockey pucks” (Swedish expression) and no god on the track!
A solution is 2.2” rims and modern tires, problems … some yes! Around 95 manufactures went from having bearings in the rims to have the bearings in the wheel axels at the front. But the old stile front rims are still produced, so this isn’t a problem. The rear rims are a different story, you have to do some modification on the Scorpion first before you can mount modern 2.2” rims.
The Scorpion drive washer is round and not a 12mm hex, and that’s what you need. I purchase ”HPI’s Racing Locking Hex Hub 12mm” and the some from AXIAL. The deferens between this two are the color. This is not the perfect solution, but still a solution that works. HPI has another type (more expensive and purple) that I will test later on ”HPI Aluminum Hex Hub Clamp Type 12mm” (Ordered).

My attention is a 26 year old racer, so I didn’t chose 2.2” rims at this time. For the rear rims I have chosen Optima 1.6” and newly produced OT-30 tires from Jose in Spain. I even tried to mount on the Scorpion 1.5”, to my surprise it actually works fin on that rim to. The different between Scorpion’s SC-84 Sand Super and Optima’s OT-30 Sand Super is that the SC-84 is slightly wider than OT-30.

At the front I have original 1.9 Scorpion rims and Amark tires still sold by CRP for $10.

To be continued!

nice work, keep it up! how's the finishing of the white repro tub? btw I think the CRP wing does look a little oversize for the TS though.

kaz_z wrote:nice work, keep it up! how's the finishing of the white repro tub? btw I think the CRP wing does look a little oversize for the TS though.

I'd agree with kaz_z. I'm loving the work so far, but I'm not diggin' the wing. It lends a certain "ricer" quality to an otherwise beautiful car. A simple, 1-layer wing would look better, I think. Awesome work nonetheless!

Okay, the forum has spoken and point taken!
Then this rice a few questions… Witch wing shall I chose?

Associated Competition Wing 6182 Associated High Down Force Wing 6183 Associated Large Wing 6186 Koyosho Wing
Should it be painted or not?

I like the Associated 6186 wing; simple & shapely. I used that wing for the Marui Galaxy I rebuilt.

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