TV Top Gear - Season 21 Episode 4 : Episode 4 Top Gear - Season 21 Episode 4 : Episode 4 7.893/10 by 112 users William Woollard looks at ways to mitigate traffic congestion, while Jeremy Clarkson examines some of the competing solutions to London’s problems and comes to a novel conclusion. Off-road motorcycle rallies have given rise to a new breed of commercial bikes. Chris Goffey assesses their leisure use off the road, and their practicality in towns. The AC Cobra still evokes a special excitement among enthusiasts. Beki Adam reviews this marriage of a big American V8 engine and a sophisticated British sporting chassis. Tiff Needell tests two Grand Prix Karts — 250cc machines capable of 150 mph. Details Casts Posters Images Title Top Gear - Season 21 Episode 4 : Episode 4 Alternative Titles 巅峰拍档, 疯狂汽车秀, Top Gear Classic (Original Series) First Air Date 1978-07-13 Last Air Date 2009-08-02 Number of Episodes 530 Number of Seasons 45 Genres Documentary, Networks BBC Two, Casts Jeremy Clarkson, Richard Hammond, James May, Ben Collins Plot Keywords , Self - Host Jeremy Clarkson Self - Host Richard Hammond Self - Host James May The Stig Ben Collins Episodes List Top Gear Season 21 :Episode 1 Episode 1 Episode 1 1989-03-21 Motoring programme featuring reviews of and reports about cars of all types. Top Gear Season 21 :Episode 2 Episode 2 Episode 2 1989-03-28 Motoring programme featuring reviews of and reports about cars of all types. Top Gear Season 21 :Episode 3 Episode 3 Episode 3 1989-04-04 Motoring programme featuring reviews of and reports about cars of all types. Top Gear Season 21 :Episode 4 Episode 4 Episode 4 1989-04-11 Motoring programme featuring reviews of and reports about cars of all types. Top Gear Season 21 :Episode 5 Episode 5 Episode 5 1989-04-18 Motoring programme featuring reviews of and reports about cars of all types. Top Gear Season 21 :Episode 6 Episode 6 Episode 6 1989-04-25 Motoring programme featuring reviews of and reports about cars of all types. Top Gear Season 21 :Episode 7 Episode 7 Episode 7 1989-05-02 Motoring programme featuring reviews of and reports about cars of all types. Top Gear Season 21 :Episode 8 Episode 8 Episode 8 1989-05-09 Motoring programme featuring reviews of and reports about cars of all types.