21. By 1990 all of the foam-filled tires had been replaced with tubeless pneumatic types. 22. The steel-wheel business makes tubeless steel disc wheels in a facility in Frankfurt, Ohio. 23. This scared away sales to Ford as many people did not initially trust the new tubeless design. 24. Also in 2015 Zipp released an alloy rimmed, tubeless ready wheelset called, Zipp 30 Course. 25. The roadster was the first American car with tubeless tires, and it offered a removable fiberglass hardtop. 26. In 1963 Becker introduced the Monte Carlo, a tubeless solid state radio, with no vacuum tubes. 27. However, tires not designed for tubeless application do not have as robust a sidewall as those that are. 28. Several companies such as Michelin and WTB have their own similar system called " Tubeless Ready ". 29. Road Tubeless rims, like UST rims, have no spoke holes protruding to the air chamber of the rim. 30. More recently, tubeless clincher tires have become popular after their successful presence on mountain bikes for the last several years.
