73 Super Stinger 400rv

[racing83x]

I am new to the Scorpion world and just purchased a 1973 or so i think SuperStinger400rv. My first question is what does "RV" stand for? How many of these were produced, and how many in white. Mine is a white one. I also noticed that it has a John deere Primary Clutch on it. Was this standard? The production date on the sled is 10/72 so i assume it is a 73 but the last owner thought it was a 74. Any help would be great

[stingerIII]

The production date shows it as an 1973 model year,the 400rv usually was a CCW 400cc with reed valves.
John Deere sleds at that time also used the CCW engines(as did other manufactures) and some with reed valves.

[racing83x]

Do you know how many white 400 rv's were built?

[mooreperformance]

All of the white sleds were 440 Rockwells. The 440 Super Stinger was available in red or white.
You either have a 400 RV Super Stinger with a 440 white hood or a 440 Super Stinger with a John Deere 400 RV engine/clutch.
Either way you do NOT have a rare sled. The 400 Super stinger came with either the CCW 400 RV or the 400 Rockwell.
Very common in 1973.

Not one of the better Scorpions, they had numerous factory recalls just to make them a moderately reliable sled.

Very high center of gravity and very tippy. First year for the Pararail and rough riding.

The 400 RV was a very average engine and the 400 Super Stinger with the 400 Rockwell (called the 400 TK) would run away and hide from it in a drag race. The 400 TK was available in red or yellow. The 400 RV was available only in red.

Scorpion had so many unsold 1973 Super Stingers at the end of the 73 season that they installed a new hood on them (with vents on the front) and made a special 1974 model. Sold em really cheap too.

[racing83x]

I am a little confused. You say all the sleds that were white were 440 rockwells. The sled i have is a 400rv in white. The motor is a 400ccw. Like i said it does have the John Deere Primary on it like you talked about.

The hood though clearly says 400 and not 440.

[mooreperformance]

Sorry, can't help you out there. Don't know about the circumstances around your sled.
There could have been differences that I never new anything about. I suggest looking at a 1973 brochure on-line.

There were many 1971-73 440 Rockwells that had bad center crankshaft seals. (a major defect in the early Rockwell/JLO twin cylinder engines) The engine needed to be torn down completely, the crankshaft pressed apart and a new seal installed. Most owners didn't want to do that (spend the money) so they sold the sled cheap or found a replacement engine.

I would guess that your sled was a 440 Rockwell with a bad center crankshaft seal and the engine was replaced with a 400 CCW RV from a John Deere. Maybe someone installed the 400 decals?

To make the sled a little more valuable you might want to consider replacing the engine with a modern 6 bolt head 440 Cuyuna, Walbro WDA6 carburetor and Scorpion roller clutch.

Not only will it be more valuable but it will be very fast!
Have fun with your White Super Stinger!
Dennis

[racing83x]

Dennis,

The 1973 brochere does show that there was 400rv's made in white, it also shows it was the most expensive model also. I just have never seen one anywhere else. There is two on vintage sleds for sale though i guess.

[mooreperformance]

That's good news for you! Swap out the John Deere clutch and you will have an original Scorpion. The factory recalls were 50% repairs on the clutch. The rest of the recalls were about overheating/vapor lock and suspension (if I remember correctly
If I can help you anymore just let me know.
Dennis

[scorp11]

The RV stands for Reed Valve and that motor was the only Scorpion built sled that used reed valves (not counting the sidewinder). The pistons are getting harder to come by, but I definitely wouldn't convert that thing to a Cuyuna. Will be worth more with the RV motor than the more Cuyuna in it. You see them around, but not a lot of them.

Never take what the brochures, test reports or what someone said was the only way it was as gospel. The brochures were generally pre-production pictures and a lot of times what's in there is not exactly as produced. I've learned over the years, Scorpion also did a lot of stuff that they didn't publish or promote. I do know for a few years in there, you could custom order your scorp in just about any color :-)

The 400 RV's were a good running motor and had plenty of power. Make sure its sealed up good and run it. There are several series of 400 / 440 CCW motors around and each has its differences if your looking for parts. John Deere guys would know the details on each series as JD used CCW motors.

I think the scorp was a 20 or 21 series, but I'd have to contact some JD engine guru's to find out for sure.

[racing83x]

Scorp11,

From what i have read and looked at the John Deere Clutch was stock on the CCW400. As you stated John Deere used this in there own sleds, and it seems like that is what came on the 400rv Super Stingers. Can you provide any info on that? Do you have any idea on how many of these white ones were built? Seems like scorpion never really documented what they did, kinda like ski-doo. My two John Deere's that i have i can just about tell you what day they were born with all the info Deere has on them.

No matter what this is my first Scorpion and I am starting to like it. I do like the fact that is has John Deere parts on it I live only minutes away from the town of Crosby, Mn and the 2013 Homecoming is in a couple of weeks. Should be fun to actually bring a Scorp there this year.

If you have anymore info on this sled it would be great.

[stingerIII]

There was a white hood 1973 400rv in our neck of the woods back in the
the 70's ,it was pretty fast in its day but the JLO Scorpions were the only
sleds locally the could spank it.But it rarely had a windshield on it(as any of our
lap mounted engined Scorpions were missing windshields).

Its ran against mostly John Deere JDX's and Roll-o-Flex
sleds and they all had the CCW engines in them at the time.Our old
71 StingerII with a 290 ss Sachs in it would out run most
of them( if you could stay on).And to add insult to injury
the Stinger II had to drag in many a Roll-o-Flex and John Deere that tried
to run with the old Sachs.(Many a melted piston in the two cylinders)

[scorp11]

The John Deere clutch wouldn't have been stock on the Scorpion. Scorpion had their own clutch they used.

Scorpion was notoriously poor about documenting a lot of stuff and didn't generally release production numbers on sleds. I don't know how to tell you to find how many of a given color were made. People can't even agree on how many Bullwhips were made. The serial numbers on the scorps tell you the year and that is about it.

[pararailer]

stinger III,
Thats a cool story, Tell me more, I am interested in them roll o flex sleds because they had a pararail type suspension.

[stinger440]

If that is a scorpion engine it will be a KEC-400/21. This engine uses a 16mm piston pin. The JD clutch works well on these. I used one on my 73 RV. Seems like I had B weights and a yellow spring. You MUST use premium fuel in this engine. If you try to use regular 87, the engine will diesel and keep running when you try to shut it down, eventually melt down. The 400/21 pistons are non existant on the shelf. They are around but you have to do some searching. The engine if tuned properly had very nice acceleration and pull.

I can't say anything about the suspension as I have only had 71's and 73's. I thought the 73 rode very well for a tunnel mount sled. I had mine wound out to 64mph on the wish o meter. At that it seemed like 164

If you want to play with the RV engines, the manifold from a 76/77 JD liquifier bolts right on and dual 34mm miks work well. I haven't tried it but I also heard boysen reeds from a mid 80's suzuki RM80 will fit right in.

[racing83x]

Thanks for all the information. Where is the best source to get new stickers for these sleds. I want to redo the hood and want to have the right stickers

[mooreperformance]

I worked for Scorpion Dealers in 1973 and John Deere Dealers in 1976 and 1977. I've had some experience with the CCW RV engines.

Any engine that is designed around a reed valve is designed to make low speed torque at the expense of high speed horsepower.
Outboard motors for instance.
(I am an outboard motor mechanic)

Reed valve engines have long strokes and small bores (like a truck engine/Harley Davidson engine). The very nature of a reed valve between the carburetor and the crankcase creates a huge restriction to air/fuel flow into the engine. They simply can't breath at high speeds!

Engines that are designed to produce torque and pull hard at low speeds (RV) must rely on low engagement clutches to benefit from the engine design. These "torque" engines always run hotter (more prone to detonation) than a high reving "horsepower" engine (that has a high speed clutch).

Low speed "torque" engines (reed valve engines) are almost always water-cooled. You don't see many high performance reed valve engines that are air-cooled. The CCW reed valve air-cooled engines are unique. They seem to run ok with a (huge) cooling fan.

Not really the best way to build an air-cooled snowmobile engine though!
Dennis

[scorplover]

I just checked out your web site mooreperformance, pretty cool. Very impressive credentials too!

[chapguy]

I know what the brochure said but I've seen a few 73 Super Stingerette's with the 400 Rv engines in them and 400 RV on the hood. Not normal but it seemed anything goes in the good old days. I wouldn't be suprized if a few white 400 Rv's were made but as Moore said it wasn't listed in the brochure. 1972 was actually the first year of the pararail, the 72 version used steel rails where the 73 was aluminum. Our local dealer got 2 1972 440 Super Stingers with the pararail, all his other 440's came with bogies.

[scorplover]

There is one for sale on Vintage Sleds right now. It was posted yesterday.

[scorp11]

Jan 16, 2013 19:11:09 GMT -5 scorplover said:

There is one for sale on Vintage Sleds right now. It was posted yesterday.

Based on the email, I am guessing it is the one this post is about