JDX Sleds from 73 to 75

[JoeRainville]

Deere introduced the Black JDX series for the 73 Model year to grow the line from the 72 Green Machines. They were still Mid-Motor sleds, with front fuel tanks.

For 1973, there was the JDX-4 and JDX-8, Deere's top of the line sled for 73.

The JDX-4 debuted the Kohler 292 cc "K295-2AX" 25 hp motor with a single Walboro carb, WDA-37. It had a steel tunnel and pan, but with aluminum centered bogies and front bumper. It came with the Salsbury 780 drive clutch and matched driven.

The JDX-8 came with CCW's first case reed motor in a Deere, the KEC 440/21, 40 hp motor with a single Walboro WDA-34 carb. This was the only time a KEC 440/21 was used by Deere. The X-8 had an aluminum tunnel and pan, with steel centered bogies. It was originally factory equipt with a Salsbury 850 drive and matched driven, but both were replaced under Mod 140. The Mod kit included a new Comet 100-C and Comet 90-D Driven.

Both the 73 JDX-4 and 8 came with a narrower 'bikini" windshield, but the larger one from the 100 series fit the machines.

For 74, there were many changes and additions to the Blitz Black JDX line up.

The JDX-4 Special replaced the JDX-4. It now came with an aluminum tunnel and pan. All JDX's for 74 recieved a dual rear shock slide rail suspension, and the infamous Goodyear "molded grouser bar" track that was as durable as bonding steel bars in a "peel joint" could be, or not very. The JDX-4 Special was powered by a CCW 340cc piston port motor, the KEC-340/5 at 32 hp. It had a single Bedix carb, and Comet 100-C / 90-D clutch set up.

The JDX-6 was new to the line up in 74, using a CCW 400cc case reed motor, the KEC 400/22. This was Deere's only 400 cc sled that was basically an underbored JDX-8 motor using the same crank. It was rated at 36 hp, and used a single Walboro WRA-31 carb and Comet clutching.

The JDX-8 aslo got the slides and molded track, replacing 73's bogies. The CCW KEC 440/21 was updated to the 40 hp KEC 440/22 that lived through the 78 Model year powering front motored Cyclones. Additional transfer ports were added, piston pin and crank pin diameter increased.

For 75, the entire JDX line up recieved new hoods, plastic gas tanks, and new extruded aluminum bumpers, along with Comet 101-C drive clutches.

The JDX-4 lost it's "Special" name, and again got a new motor, the Kioritz KEC 340/22 case reed motor, making the entire JDX line up case reed.

The JDX-8 had an optional CDI ignition, similar to what was used on the 74 295/s. It also got a power increase with a 295/s type tuned pipe and separate muffler, raising power to 46 hp, and giving it and the 800 with the same system a very distintive sound.

1975 was the end of the road for the mid-motor JDX line, being replaced in 76 by the Liquid Cooled Liquifire as Deere's top consumer sled. However, many of the inovations first found on the JDX and 74 295/s line up were later found in updated form on the new Liquifire/Cyclone line up. This includes Deeres slide suspension, (with one shock) and the Cyclone's motors, Mikuni carbs (first used on the 295/s), and CDI ignition.

-Joe Rainville
"Tech-Ed"

As always guys, feel free to add anything I may have overlooked!

[JDXsand00s]

Did the identification tag with serial number location change from 74 to 75 models? I know from 73 to 74 changed to incorporate date of manufacture.

[400brian]

One small addition.

The '73 JDXs came with a smaller windshield. It was short and narrow, just a bit wider than the dash. Most no doubt got replaced with the full windshield, once in a while you'll see one on ebay with the small one.