Comstar wheel

Comstar wheel

First generation Comstar front wheel fitted to a 1978 Honda Hawk CB400A
Invented by Honda
Launch year 1977
Company Honda (DID for rims)

The Comstar wheel, sometimes referred to as Com-stars or stylised as ComStar,[1][2] was a composite motorcycle wheel that Honda fitted to many of its motorcycles from 1977[3][4] to the mid 1980s. Its design allowed it the option of being fitted with tubeless tyres and its use on the Honda CX500 was the first time tubeless tyres had been designed for a production motorcycle.[5][6]

Background

The Comstar was Honda's replacement for the tension spoked wheel. Whilst spoked wheels offered a degree of flexibility to help absorb road imperfections, they also required periodic maintenance to ensure correct spoke tension and required the fitment of an inner tube. Honda claimed the Comstar design combined the strength of a cast wheel but allowed a predetermined level of radial flex like spoked wheels.[7]:27 Comstar wheels also allowed the fitment of tubeless tyres which, like other alloy wheels,[8] helped to reduce unsprung mass,[9] although not all models fitted with Comstars had tubeless tyres.

Silver Comstar wheel on an Honda RCB endurance race bike
Comstar wheel on a Honda RCB endurance race bike

Honda debuted Comstars on their FIM European Motorcycle Endurance Championship winning[10] RCB-941[7]:27 production endurance race bikes for the 1976 season.[11]:60 Honda first fitted Comstars to its road going motorcycles in 1977 on models such as the CB400T Dream, CB750F2 and the later flagship CBX1000. A special lightweight version was also used on HRC's failed oval-piston four stroke GP motorcycle, the NR500,[12]:105 and the later NS500 two-stroke ridden by Freddie Spencer.[13]

Gold reverse Comstar front wheel from a Honda CB400NC
Third generation 'Reverse' Comstar front wheel on a 1982 Honda CB400NC Super Dream

Some later models came fitted with what were known as reverse Comstars.[14]:68 These had the spoke sections that looked they were assembled the other way round, hence the term "reversed". This style of Comstar was often given an anodized colour finish such as gold[1] or black[14] with silver detailing.[15]:54

They were said to be hard to keep clean due to tiny crevices.[16]:40

Construction

To manufacture the Comstar wheels Honda used an extruded aluminium-alloy rim made by D.I.D[17]:37 that was fastened to the spokes using aluminium rivets. The spoke pieces were bolted to the rim with steel bolt and nut fastenings in either three, five or six pointed star configuration. What metal the spokes were made from depended on the model of motorcycle. The CB400T for example used steel for the spokes and alloy for the rim, whilst the CBX and the Super Dream used alloy for both the spokes and rims to further reduce unsprung mass. This type wheel was considered "maintenance free" with no user serviceable parts and Honda had "Do Not Disassemble" stamped on the wheel rim alongside other markings such as the fitment size. For its use on the NR500 GP machine, the wheels were made from magnesium with titanium used for the fasteners.[18]:49 Composite wheels were also cheaper to produce than their cast alloy equivalents.[19]:42

Successor

From the early 1980s Honda had begun equipping newer models with cast wheels called ComCast [20]:51 stating "...that technology has solved the casting porosity problem and that cast wheels are now used on Hondas for styling and marketing reasons".[21]:47 ComCast wheels were a combination of pressed-together cast aluminium hub and spokes with a hollow extruded aluminium rim.[22]:52

Similar products

Astralite wheel fitted to an early 1980s Hesketh

At the same time as Honda's Comstar, Dawson Harmsworth, a business in Sheffield, England produced a similar composite wheel from 1977 with generally comparable appearance, materials and construction. Initially intended for road racing applications, the wheel was specified for some models in the early 1980s Hesketh low-volume production road motorcycle range. Hesketh claimed the wheel was in development before Honda unveiled the Comstar, but that development had taken more time.[19]:42 Twenty years after the original business closed, the wheel is again being manufactured by a new business established by a former employee of Dawson Harmsworth.[23][24][25][26][27]

References

  1. 1 2 CB400N Super Dream (sales brochure), Honda UK Limited, 1982
  2. ↑ ComStar wheels - How they work., American Honda Motor Co. Inc, 1978
  3. ↑ Richard Backus (May–June 2010). "The Honda CB750F Super Sport". Motorcycle Classics. Retrieved 2015-05-30.
  4. ↑ Clement Salvadori (21 January 2006). "Retrospective: Honda CB750F Super Sport (SOHC): 1975-1978". Retrieved 2015-05-30.
  5. ↑ Richard Backus (March–April 2008). "The CX500: Under the radar". Motorcycle Classics. Retrieved 2015-05-31.
  6. ↑ Margie Siegal (May–June 2009). "1983 Honda CX650 Turbo". Motorcycle Classics. Retrieved 2015-05-31.
  7. 1 2 "Fly the Hawk (Honda advert)". Cycle World: 27. September 1977.
  8. ↑ "New ideas in wheels, forks and shocks", Cycle World, p. 65, June 1976
  9. ↑ The bare facts beneath a beautiful body (sales literature), Honda UK Ltd, 1981
  10. ↑ "A Short History of Endurance". FIM. 10 February 2013. Retrieved 2015-06-15.
  11. ↑ Allan Girdler (January 1977). "The American Motorcycle Press on a semi-secret tour of Honda's Toy Shop". Cycle World: 58–61, 86–91.
  12. ↑ Aaron P. Frank (28 May 2003). Honda Motorcycles. MotorBooks International. ISBN 978-0760310779.
  13. ↑ Wilson, Hugo. (1993) The Ultimate Motor-Cycle Book p.115 1984 Honda RS500. "Lightweight racing-type Comstar wheels". Dorling Kindersley ISBN 0751300438 Accessed and added 2014-06-12
  14. 1 2 Simon Whittaker (August 1988). "Honda Superdreams - bread and butter biking". Motorcycle Illustrated: 66–68.
  15. ↑ "Classic Motorcycle Mechanics". Mortons Media Group. June 2013: 52–55.
  16. ↑ "The New Honda 400 Hawks Test". Cycle (magazine). Ziff Davis: 38–46,89–92. September 1977.
  17. ↑ "Road Test:CB750F2". Cycle World: 36–40. June 1977.
  18. ↑ John Ulrich (November 1981). "Fast Freddie Spencer and the NR500". Cycle World: 46–49.
  19. 1 2 Allan Girdler (January 1980). "A Vee for Victory". Cycle World: 40–43.
  20. ↑ "Cycle World Test: Honda 1000 Interceptor". Cycle World: 48–53. July 1984.
  21. ↑ "Honda CB1100F: Better Late Than Never, Honda Sets Out To Win the Horsepower Per Dollar Struggle". Cycle World: 44–49. January 1983.
  22. ↑ "Cycle World Test: Honda Ascot VT500". Cycle World: 50–55. August 1983.
  23. ↑ "Manufacturer's advert. Astralite wheels, Dawson Harmsworth, 401-403 Penistone Road, Sheffield.", Motor Cycle News, p. 9, 22 September 1982
  24. ↑ Motor Cycle News 24 April 1991, p.24 Manufacturer's advert. Astralite wheels, Dawson Harmsworth, Road & Racing. Gold and black anodised finish, 16"17"18" dia 2" to 6" wide rims, for fitting to Suzuki, Yamaha, Honda, Kawasaki. Specials to fit Ducati, Laverda, Guzzi, Rotary Norton & many more. Accessed 2015-06-27
  25. ↑ "Astralite wheels", Classic Racer, 28 June 2013, archived from the original on 2016-03-04
  26. ↑ Astralite wheels by Rennstar, Rennstar
  27. ↑ Astralite Wheels - Care and Maintenance, Hesketh Owners Club, 18 August 2012
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