Pipe, tape and rings: how the RC drift tyre became a controlled part

US 7,694,705 B2, "Drift tire and remote control car having tire attached thereto", is assigned to Yokomo Ltd and names Tomoaki Yokobori as inventor. Its priority is JP2003-351928, 10 October 2003; the US filing followed on 8 October 2004; it was granted on 13 April 2010.

The background section is the interesting part for a historian. It describes how drifting was being done at the time: fitting a smooth resin pipe over the tyre, winding tape around the tyre, or changing the floor instead — running on P-tile, or waxing the surface — and it names the problems with each. That is a manufacturer's own account of the state of practice as of its filing.

Two cautions belong here. The patent dates the description of the pipe and tape methods, not their invention; nothing in this material establishes when drifters first started doing it. And the claims cover a specific thing — rings of resin, rubber or metal fitted into grooves in the tyre — not the plastic drift tyre as a category. A patent on a ring tyre is not a patent on hard plastic.

Yokomo's own new-products page for January 2004, captured by the Internet Archive on 18 January 2004, already lists the product on sale: ZR-DR01, a Zero One touring-car drift tyre with rings, at ¥800, alongside ZR-DRP polycarbonate spare rings at ¥380. The listing frames the rings as a tuning item — the number fitted adjusts "the amount of drift". When the Zero One first went on sale is not established by this material; only that it was on sale by that capture.

That is a specific design idea, and it is worth stating plainly at 1/10 scale: the grip level was meant to be set by the parts you clipped on, on a car whose whole tyre sits inside a wheel a couple of inches across. A December 2005 Yokomo products page, read through a 9 May 2007 capture, describes the kit tyre as "patent applied for" and "super-low height" — the application was still pending five years before it granted.

Tamiya's product pages give a parallel chronology with its own dates on the page, which is stronger evidence than a crawl date. The page for item 58349, dated 21 July 2005, describes a drift tyre made from a "rubber base compounded with special resin". Item 58392, on sale 28 July 2007, repeats the same description.

By the page for item 58428, dated 19 March 2009, the description has changed: an all-resin "Super Drift" tyre, with little performance change from heat or wear. Materials are named here only as each maker states them; Tamiya's phrasing is the evidence, not a compound spec.

That sentence about heat and wear is the technical turn. A tyre whose behavior does not drift over a session is a tyre an organizer can write into a rulebook and expect to behave the same in heat two as in heat one. The undated OP.1020 page means the first appearance of Tamiya's all-resin tyre is not settled by this material either.

• 10 October 2003 — JP2003-351928, the priority for Yokomo's drift-tyre patent.
• by 18 January 2004 — ZR-DR01 Zero One and ZR-DRP spare rings listed on sale on Yokomo's site.
• 8 October 2004 — US filing of the patent application.
• 21 July 2005 — Tamiya 58349 page: drift tyre of rubber base compounded with special resin.
• 28 July 2007 — Tamiya 58392 on sale, same material description.
• 19 March 2009 — Tamiya 58428 page: all-resin Super Drift tyre.
• 13 April 2010 — US 7,694,705 B2 granted.
• 28 March 2012 (capture) — D1-10 rules: Yokomo ZR-DR04 only, €15 for four.
• December 2012 — Yokomo event rules: Zero-One R2 (ZR-DR04) only.
• 1 June 2013 (capture) — D1-10: ZR-DR05 Zero One R4 for carpet, supplied by Yokomo.
• 29 October 2014 (capture) — D1-10 lists a DS Racing tyre.
• 24 May 2016 (capture) — D1-10: RWD only, DS Racing RWD FFF-zero Mark II.

Yokomo's rules for its December 2012 event, read through a 22 January 2013 capture, do not describe a tyre category. They name a part number, and they specify how it is mounted: the "YOKOMO PAT.P" marking must face outward, so a judge can see it from the edge of the track.

D1-10's rulebook captures show the same mechanism in Europe, and then show it moving. In March 2012 the rule is Yokomo ZR-DR04 only, priced in the rules at €15 for four. By June 2013 it is the ZR-DR05 Zero One R4 for carpet, supplied by Yokomo. By October 2014 the named tyre is a DS Racing item, listed as "Open eu 2014 carpet CS FFFzero" — a line that still belongs to the AWD counter-steer era the series was running. By May 2016 the rulebook reads "RWD only: DS Racing RWD FFF-zero Mark II".

Two changes are happening in one line of text. The spec tyre passes from the maker that patented the ring tyre to a specialist tyre maker, and the class the rule governs changes from CS cars to RWD. The tyre rule is where that transition is legible, because a mandated tyre has to be a tyre the whole field can actually drive.

The ring is gone from most cars, but two habits from this period are still standard at 1/10. The first is that the tyre is chosen against the surface — carpet, P-tile, polished concrete, asphalt — as a named part number from a named maker, not as a compound you feel out. The second is the spec tyre itself: a track or a series names one tyre so nobody buys grip, and the field's setup work moves to gyro gain, ride height, spring and weight instead.

That is the durable consequence of the documents above. The pipe-and-tape era ended not because someone found a better material, but because the tyre became a part with a number on it that an organizer could write into a rule and a judge could check from the outside of the wheel.