NOTE: Speed-X bugs are a favorite of mine, particularly the “T-bar” 500 and 501 models. From the best sources, here’s a quick timeline of the Speed-X bugs:
BEFORE SPEED-X. The Speed-X style bug was first associated with Electro Manufacturing Co. of Fresno, Calif., which made two bugs that were the predecessors of the “T-Bar” Speed-X bug. The Electro Bug used the solenoid to control the output for dits, and the key had a box mounted on the base to house those parts. An Electro Bug Jr. model was also manufactured that was essentially the Electro Bug key without the relay and solenoid apparatus.
EARLY SPEED-X. In 1934, Steward Johnson bought the Speed-X name and moved the company from Fresno to San Francisco. Johnson changed the company name to the Speed-X Radio Manufacturing Co., located at 30 Ninth St. in San Francisco. Johnson built what are today called the “early Speed-X bugs” from 1934 until he sold the company to Les Logan in 1937. The early Speed-X bugs are characterized by no nameplate; they also used the traditional thumbpiece and finger knob. Early Speed-X keys also universally used the same sort of damper — a wheel held in a slotted post. Other early Speed-X characteristics include the unusual thumbpiece (paddle) that was asymmetrical and the unusual “reverse” pivot frame bug.
LES LOGAN SPEED-X. Les Logan built Speed-X keys from 1937 until he sold the company in 1947 to the E.F. Johnson Co. The Logan-era Speed-X bugs are plentiful on the 
used market. Logan added nameplates to his line of keys; some earlier ones also include serial numbers, though the majority do not. The keys are also universally feature double paddles and have no finger knob. The paddles also have two rings inscribed on them, referred to by collectors as the “bulls eye” paddles. Logan paddles have a low-gloss finish, and the paddles have a very fiber-like feel to them. They do not shatter like plastic, but will “mush over” when broken. The cast parts of the key — notably the pivot frame on both the T-bar models and the regular models — tend to be very fragile and will break easily if dropped. It isn’t uncommon to see a Speed-X T-bar bug listed on eBay with one or both parts of the “T” broken and missing. I have had a couple of instances where the “Vibroplex style” pivot frame on a model 515 was broken in shipment or broke once it arrived; these pivot frame often crack near the top pivot adjustment. The feet on the Logan-era bugs were on pins that were pressed into the base.
E.F. JOHNSON ERA. In 1947, Logan sold Speed-X to the E.F. Johnson Co., and it continued production of the Speed-X keys, both the bugs and the straight keys. Johnson simply altered the Speed-X nameplate to add its company name and continued to churn out the moderately priced keys. At some point, Johnson changed the pivot frame on the 501 key, removing the “T-bar” and making it an “ear-less” design. The new pivot frame also was the mounting point for the updated E.J. Johnson nameplate, which arrived in the 1960s and was used on the bugs and in advertising. Johnson made changes to the finger paddles, making them molded plastic instead of flat bakelite (while keeping them adjustable), and the company also changed the damper weights; Johnson made the weights larger in diameter and flatter, while employing a unique clip design that allowed users to adjust the weights without tightening or loosening any screws. The dampers on the Johnson-era Speed-X bugs stayed the same. The bugs were available in two finishes, chrome base and a painted, black crackle base.
WILLIAM NYE, THE MORSE KEY GUY. In 19721, E.F. Johnson sold its line of CW keys to the William Nye Co., which spelled the end of the Speed-X bug, but not the Speed-X straight keys. Nye continues to manufacture Speed-X straight keys from his factory in Priest River, Idaho. The company previously had been located in Bellevue, Wash.
Gathered from the Internet:
The company was founded in 1972 by William Nye in Bellevue, Washington who retired in 1986. Bill Nye, Jr. (WB7TNN) and his wife Sally operate the company, and they employ a part time key assembler and an electronics technician.
William Nye was born in North Dakota in 1912 and moved to the Seattle area in 1924. He has been an amateur radio operator (W7DZ) since age 12. He owned a business machine company until he sold it and retired in 1971. He established the William M. Nye Company as a retirement business.
The Nye company bought the SPEED-X trademark from the E.F. Johnson Company in the fall of 1972. The Nye company bought tooling to manufacture keys, low pass filters, matchboxes, and sounders. Bill Jr. does not believe that they bought the tooling to manufacture bugs.
Nye’s present line of keys are manufactured on site, though casting, painting, and some machine functions are contracted out. Small parts are manufactured on site using a variety of stamping and drilling machines. Many of these machines have been modified by Bill Jr. to power them with air or hydraulic pressure. He is an inveterate tinkerer, and does most of the manufacture of small parts himself. Screws are bought from vendors, and key assembly is done by a part time employee.
Nye is using the same key casting molds that were used by the Les Logan and E.F. Johnson Companies. These molds were re-worked in 1972 by a machine shop. This involved polishing, milling, and filling them. These molds were acquired from the Johnson company, and it is doubtful that new ones have been made since the 1930’s. Their key bases are cast in Zinc by a sub-contractor in the Seattle area. Zinc is used because of ease of casting, low cost, and solid weight. (Information gathered from the N7CFO KEYLETTER’S, Story by Lynn A. Burlingame N7CFO)
Nye’s Speed-X keys straight keys continue to be manufactured and sold.