Tribsa
Encyclopedia
The Tribsa, or Tri-B.S.A., was a custom built
cafe racer
or off road motorcycle of the 1960s and 1970s. Its name was an elision of "Triumph" and "BSA"
. The purpose was to combine the best elements of each marque to give a superior bike to either.
A Tribsa involved a Triumph parallel twin engine installed in BSA motorcycle motorcycle frame. Although both the BSA A65
and the Triumph
650 cc twins engines were overhead valve (OHV) units, only the Triumph had twin camshafts, which facilitated tuning for greater power output. The BSA frame was a duplex-cradle design which was considered stiffer and stronger than the Triumph's single downtube item.
A Tribsa was built experimentally at Meriden by Triumph in 1973 using surplus BSA A65 frames. This led to a "factory Tribsa" which was to use the BSA A65 frames with the 650 cc TR6 engine. Not many of these hybrids were produced and factory records are vague.
A popular alternative to the Tribsa was the "Triton"
which combined a Triumph engine in a Norton Featherbed frame
. In contemporary vintage off road events, Tribsas compete in motocross
, enduro
, and trials
.
Custom motorcycle
A custom motorcycle is a motorcycle that is highly stylized or which treats aspects such as frame geometry, engine design, or paintwork in an unusual way compared to standard manufacturing. Custom motorcycles are unique or individually produced in a very limited quantity, as opposed to "stock"...
cafe racer
Café racer
A café racer is a type of motorcycle as well as a type of motorcyclist. Both meanings have their roots in the 1960s British counterculture group the Rockers, or the Ton-up boys, although they were also common in Italy, Germany, and other European countries...
or off road motorcycle of the 1960s and 1970s. Its name was an elision of "Triumph" and "BSA"
Birmingham Small Arms Company
This article is not about Gamo subsidiary BSA Guns Limited of Armoury Road, Small Heath, Birmingham B11 2PP or BSA Company or its successors....
. The purpose was to combine the best elements of each marque to give a superior bike to either.
A Tribsa involved a Triumph parallel twin engine installed in BSA motorcycle motorcycle frame. Although both the BSA A65
BSA A65 Star
The BSA A65 Star was a Birmingham Small Arms Company motorcycle aimed at the US market for unit construction twins. As well as giving a clean look to the engine, with the pushrod passages part of the cylinder block casting, unit construction reduced the number of places oil could leak from...
and the Triumph
Triumph Bonneville
The Bonneville is a range of British motorcycles, made in three different production runs from 1959 to 1983, and 1985 to 1988, by the now-defunct Triumph Engineering in Meriden; and since 2001, by Triumph Motorcycles in Hinckley. It is named after the Bonneville Salt Flats, Utah, where Triumph and...
650 cc twins engines were overhead valve (OHV) units, only the Triumph had twin camshafts, which facilitated tuning for greater power output. The BSA frame was a duplex-cradle design which was considered stiffer and stronger than the Triumph's single downtube item.
A Tribsa was built experimentally at Meriden by Triumph in 1973 using surplus BSA A65 frames. This led to a "factory Tribsa" which was to use the BSA A65 frames with the 650 cc TR6 engine. Not many of these hybrids were produced and factory records are vague.
A popular alternative to the Tribsa was the "Triton"
Triton motorcycle
The Triton was a modified café racer motorcycle of the 1960s-1970s. The name derives from a contraction of Triumph and Norton, the two brands of motorcycle combined.The intention was to combine the best elements of each to give a bike superior to both...
which combined a Triumph engine in a Norton Featherbed frame
Featherbed frame
The featherbed frame was a motorcycle frame developed by the British Norton motorcycle company to improve the performance of their racing motorcycles around the twisting and demanding Isle of Man TT course in 1950. It was considered revolutionary at the time, and the best handling frame that a...
. In contemporary vintage off road events, Tribsas compete in motocross
Motocross
Motocross is a form of motorcycle sport or all-terrain vehicle racing held on enclosed off road circuits. It evolved from trials, and was called scrambles, and later motocross, combining the French moto with cross-country...
, enduro
Enduro
Enduro is a form of motorcycle sport run on courses that are predominantly off-road. Enduro consists of many different obstacles and challenges...
, and trials
Motorcycle trials
Motorcycle trials, also termed observed trials, is a non-speed event on specialized motorcycles. The sport is most popular in the United Kingdom and Spain, though there are participants around the globe....
.
External links
- Cafe racer at the Open Directory ProjectOpen Directory ProjectThe Open Directory Project , also known as Dmoz , is a multilingual open content directory of World Wide Web links. It is owned by Netscape but it is constructed and maintained by a community of volunteer editors.ODP uses a hierarchical ontology scheme for organizing site listings...