BSA Royal Star

Infobox Motorcycle
name=BSA Royal Star


aka=BSA A50, BSA A65
manufacturer=flagicon|UK BSA
parent_company=
production= 1962-1970
predecessor=BSA A10
successor=
class=
engine=498cc and 649cc air cooled twin
wheelbase=convert|54.75|in|cm
length=convert|81|in|cm
width=convert|11.7|in|cm
height=
seat height= convert|32|in|cm
power= 38bhp @ 5800 RPM
torque=
dry weight=comvert|392.4|ib|kg
fuel_capacity=4 gallons
fuel_economy=50mpg
transmission=four speed gearbox to chain drive

The BSA Royal Star is a British motorcycle that was a radical new design for BSA that paved the way for a whole range of very successful unit construction twins. As well as giving a clean look to the engine, with the pushrod passages part of the cylinder block casting, unit constrution reduced the number of places oil could leak from.

Development

Bob Fearon, Managing Director and General Manager of BSA recognised the need for a completely new look that built on the best features of the A10's but would succeed in the potentially lucrative but competitive US market. Working with Chief Development Engineer Bert Perrigo they developed the unit construction "Star twins". Launched in 1962 the BSA Royal Star was available as the A50 (500cc) and A65(650cc) versions and was widely exported to the USA and Australia as well as becoming a top seller in the UK in the early 1960s.'cite book | last = Clarke | first = R.M. | title = BSA Twins 1962 - 1973 | publisher = Brooklands Books Ltd | isbn = 1-85520-337-5 ]

The Royal Star had a relatively small single Amal monobloc carburettor but in 1964 new pistons and a new gearbox improved performance.

Gallery

References

Links

* [http://www.bsaoc.demon.co.uk/intro.htm BSA Owners Club BSA numbering reference page]
* [http://www.britishclassics.co.za/British_Classics_bike_build_diary/BSA_A50_Royal_Star_500cc/British_Classics_BSA_A50_Royal_Star_500cc.htm Royal Star rebuild diary]