Avid enthusiasts have always had a knack for identifying the most suitable collectible motorcycles. In recent years, there has been a growing interest in collectible motorcycles that has resulted in a gradual increase in value. Interest in collectibles has increased as some models keep getting rarer while others gain acceptance into the collectible category.

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Homologation bikes in the road-going form are growing ever-rarer since only a few units made it off production lines. At the same time, a section of collectors also accept off-road dirt bikes as worthy collectibles. Niche Italian bikes and iconic British classics share the same rarity to a reasonable extent. Most of these exotic bikes came at a premium and still cost a fortune in today's market. According to recent data, here are some collectible motorcycles to watch closely in 2021.

9 1986 Yamaha RZ500

1986 Yamaha RZ500 parked
Via raresportbikesforsale.com

When looking at the best motorcycles worth collecting in 2021, the Yamaha RZ500 cannot be left out. The bike was inspired by Kenny Roberts' all-conquering YZR500 GP sports motorcycle. After its launch, the RZ500 was an instant success among young riders and racetrack enthusiasts. However, the Yamaha RZ500 was not officially sold in the US due to strict emission regulations under the Environment Protection Agency.

1986 Yamaha RZ500 parked
Via shannons.com

The Yamaha RZ500 is growing in popularity since it evokes the nostalgic feels and sounds of two-stroke bikes that existed only for a specific period. This sports bike packs a 500cc two-stroke liquid-cooled V4 powerplant that produces 85bhp at the rear wheel. As more buyers creep into the sports bike market, the $20K price mark might climb higher.

8 1984 Honda XR500

1984 Honda XR500 parked outside
Via mecum.com

Despite being a viewed as cheap dirt bikes in previous years, the recent shift in the outlook and perception of dirt bikes has improved their sales. Original Honda XR500s were sold with a specific Flash Red paint job. These bikes featured plastic handguards, hydraulic front disc brakes, plastic gas tanks, and Pro-Link rear suspension.

1984 Honda XR500 parked outside
Via mecum.com

The Honda XR500 is powered by a 498cc RFVC OHC single-cylinder dry-sump engine paired to a 5-speed transmission. This type of engine brings back memories of hard-riding bikes that endured wet storage with minimal fuss. Although two XR80's sold a while back for $13,650, it's worth anticipating that this might ignite a buying craze in the coming year.

7 1980 MV Agusta 750 S America

1980 MV Agusta 750 S America parked outside
Via pinterest.com

The MV Agusta 750 S America is rare in today's market since these were limited-production bikes in the 1970s. The bike is unique for its red and silver paint job on an attractive body profile, making it one of the most stunning motorcycles of its time.

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1980 MV Agusta 750 S America parked outside
Via pinterest.com

Italian classics are famous for their hand-crafted quality, and the 750 S Americana is no different. The bike boasts an air-cooled 788cc four-cylinder 8-valve four-stroke DOHC engine coupled to a 5-speed transmission. The MV Agusta 750 S America had a 32-per cent increase in sales in 2020 compared to 2019, indicating the possibility that its value could rally slightly to the upside.

6 1953 Indian Chief

1953 Indian Chief parked outside
Via mecum.com

After the Second World War, the Chief was the only pre-war Indian motorcycle model in production. The Indian Chief gained popularity for its extensive and heavily bedecked bodywork that showcased American motorcycles' pride. Throughout its lifetime, the Indian Chief competed favorably with another all-time American favorite, the Harley-Davidson.

1953 Indian Chief parked outside
Via mecum.com

Indian Chief models that reigned between 1940 and 1953 feature distinctly sprung rear ends and swooping skirt fenders that make them appealing to date. Indian Motorcycle Company closed operations from 1953 to 2011, making these classic motorcycles a real collector's item. Although Indians and Harleys have closely-linked values in the current market, most collectors are keeping an eye to find out whether the Indian bikes tip the scales in their favor.

5 1955 Vincent Black Shadow

1955 Vincent Black Shadow parked outside
Via pinterest.com

The Vincent Black Shadow embodies the engineering excellence, innovation, and high performance that avid riders associate with classic English motorcycles. When the Black Shadow was announced in 1948, the company labeled and marketed it as the world's fastest production motorcycle.

1955 Vincent Black Shadow.
Via silodrome.com

The Vincent Motorcycles ceased operations in 1955, making its last production series a highly sought-after collectible. The Black Shadow is powered by an air-cooled 50-degree 998cc four-stroke V-Twin engine that pushes it to an impressive top speed of 125mph. The bike's value has been declining recently, indicating that the price could either go up as buyers take advantage of the low price or continue going down.

4 2006 Ducati 999R

2006 Ducati 999R parked outside
Via totalmotorcycle.com

The Ducati 999 superseded the Ducati 998, Ducati 996, and the Ducati 916 models and was a success in the Superbike World Championships. The 999R model stood out also for its controversial styling, featuring a stacked headlight profile unseen in previous Ducati designs.

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2006 Ducati 999R parked outside
Via totalmotorcycle.com

The Ducati 999R boasts a powerful liquid-cooled 90-degree 999cc four-stroke DOHC belt-driven L-Twin that generates 150bhp and 79.7lb-ft maximum torque. The bike's 6-speed transmission allows it to achieve a top speed of over 170mph. As a limited homologation model, the Ducati 999R is set to benefit from the recent appreciation of performance sports bikes.

3 1989 Kawasaki KX60, KX80

1989 Kawasaki KX60, KX80 parked outside
Via shpock.com

After its debut, the Kawasaki KX80 achieved tremendous success in the mini-bike motocross category. The bike edged out competition from the Yamaha YZ80, the Honda CR80R, and the Suzuki RM80 for a few successive seasons. Kawasaki's success in this category continued with the introduction of the KX60 model.

1989 Kawasaki KX60, KX80 parked outside
Via vitalmx.com

The KX80 and KX60 made their mark by inspiring the Kawasaki Team Green to make history by becoming the most successful program in youth motocross development. These classic off-road bikes have enjoyed increased attention from modern collectors lately. Their appeal has also gone up since plastic parts have been gradually phased out in current rides.

2 1962 Triumph Pre-Unit Bonneville

1962 Triumph Pre-Unit Bonneville
Via: Mecum.com

Johnny Allen set a 214.47mph world land speed record at the Bonneville Salt Flats on Triumph's Streamliner. The Triumph T120 motorcycle unveiled in the 1959 model year bore the Bonneville name badge to commemorate this record. The pre-unit construction model had a separate primary case, crankcase, and gearbox all bolted together externally.

1962 Triumph pre-unit Bonneville
Via mecum.com

The pre-unit construction model was based on the Triumph Tiger T110, and it features a high-performance inlet camshaft and Amal Monobloc carburetors. The bike packs a 649cc air-cooled vertical twin OHV engine mated with a 4-speed constant mesh gearbox. The 2001 remake revived interest in this British classic; therefore, it's wise to keep a keen eye on this model.

1 1947 Harley-Davidson EL/FL Knucklehead

1947 Harley-Davidson EL.FL Knucklehead
Via youtube.com

Avid Harley-Davidson enthusiasts treasure the Knucklehead models for their distinct engines. Harley-Davidson built the Knuckleheads in a short production run between 1936 and 1947. The 1947 EL/FL Knucklehead is incredibly iconic because it marked the last production year before the Panhead engines became the top-of-the-line choice.

1947 Harley-Davidson EL,FL Knucklehead
Via pinterest.com

The EL/FL Knucklehead features a 45-degree pushrod actuated two-cylinder OHV V-Twin engine coupled to a four-speed gearbox. These Knucklehead motorcycles are the first to feature overhead valves, making them valuable by today's collectible standards. 2020 witnessed a new Knucklehead bidding record, and this sheds a bit of hope for a ripple effect that might increase their overall appeal in the coming year.

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