Highlights
- One-off bike with Triumph engine on Norton Featherbed wideline frame
- Impressive history file
- £6000 engine rebuild in 2009
The Appeal
Triton motorcycles were hybrid motorcycles built from the 1950s to the 1970s that involved fitting Triumph engines into Norton frames. Because no factory offered Triton motorcycles, they were typically privately constructed, although some UK dealers offered complete bikes. The aim was to combine the best elements of each marque and thus gain a bike superior to either. The name 'Triton' is a contraction of Triumph and Norton; 'Triton' was the name of a mythological Greek God.
During the period in which Triton motorcycles were constructed, the Norton Featherbed frame was regarded as the best-handling frame. Triton bikes aimed to combine the ‘best engine’ with the ‘best frame’ by replacing the standard Norton engine with a Triumph parallel-twin engine. Although ‘best’ is subjective, a popular engine choice was the Triumph Bonneville unit with twin carburettors and twin camshafts. The Triumph engine was seen as an upgrade because the Norton 650 and 750 vertical twin engines were known to have reliability problems.
This example combines a 1954 Norton Model 88 Dominator ‘Featherbed’ frame with a 1955 Triumph ‘Pre-Unit’ 6T Thunderbird engine.
The History and Paperwork
- Current V5
- Engine rebuild photos
- Past MoT certificates
- Lots of past invoices
- Haynes manual
- Sales invoice from 2022
- Non-transferable registration number
The vendor bought the bike in April 2022, but with family and other commitments, and another bike, he feels he doesn’t use it enough and has decided to part with it.
It comes with a big file of paperwork including many past invoices, past MoTs, and a Haynes manual for the Triumph Pre-Unit Twins. There are also photographs showing the components for the engine laid out before rebuild.
The Exterior
- 1954 Norton Model 88 Dominator Featherbed frame
- Handmade aluminium fuel tank
- Smiths instruments
- Brightwork all excellent
- Smart black leather saddle
- Swan necks fitted, clip ons and other spares included
- New Akront rims
- New Avon Roadrider tyres with plenty of tread
- Handlebar mirrors
The Featherbed frame was a motorcycle frame invented by the McCandless brothers, and offered to the Norton motorcycle company to improve the performance of their racing bikes in 1950. It was considered revolutionary at the time, and the best handling frame that a racer could have. Later adopted for Norton production motorcycles, it was also widely used by builders of custom hybrids such as the Triton, becoming legendary and remaining influential to this day.
This bike looks fantastic from all angles, and has clearly been carefully looked after by successive owners. The aluminium fuel tank was handmade, the vendor believes, by a fabricator who had previously worked for the Benetton F1 team.
The Mechanics
- 1955 Pre-Unit Triumph 6T Thunderbird engine with twin carburettors
- 750cc Morgo conversion
- Engine rebuild in 2009
- 5-speed gearbox
- 20-tooth gearbox sprocket
- Amal carburettors
- Remote oil filter
- Runs on modern synthetic oil
- Manx forks and steering head yoke
- John Tickle twin leading-shoe front brake
- Full service in March 2023
The engine here is from a 1955 Triumph 6T Thunderbird, as is evident from the ‘paper dart’ logo on the chain-case cover. The 6T Thunderbird used a variant of the earlier Speed Twin's parallel-twin engine, bored out from 500cc to 650cc to give the added horsepower American customers demanded.
The term ‘pre-unit’ was coined only after such engines were succeeded by ‘unit construction’ designs. Pre-unit particularly applies to BSA/Triumph's single- and twin-cylinder bikes made before this firm adopted unit construction in the early 1960s. (By contrast, Norton and Royal Enfield never advanced beyond pre-unit construction.) By 1963, all Triumph engines were of unit construction so it became necessary to differentiate.
In 2009 the engine was completely rebuilt and fitted with a Morgo 750cc Big Bore Kit.
The vendor reports that the bike rides and handles beautifully, but he just doesn’t get to ride it often. Past MoT certificates suggest that the bike has covered less than 700 miles since 2012.
Summary
The ‘café racer’ is a genre of sport motorcycles that originated among British enthusiasts of the early 1960s in London. Café racers were standard production bikes that were modified by their owners and optimized for speed and handling for quick rides over short distances. As owners became more experimental, they would fit engines in different frames and the Triton was a typical example, a homemade combination of a Triumph engine in a Norton Featherbed frame.
This is a unique, high-performance bike with numerous top-notch mechanical upgrades, but at the same time it’s a machine that will turn heads and start conversations wherever it goes, and would be the centre of attention at any classic bike event.
Notice to bidders
This item is sold on an ‘As is Where is’ basis. The condition of this item is the opinion of the seller and may differ from your own opinion. Photos and listing descriptions are for guidance purposes only*.** Car & Classic do not warrant listing accuracy. Full inspection is recommended. Viewings are at the seller’s discretion. Buyer is responsible for delivery and collection of any item purchased.*
UK-registered cars and motorbikes on Car & Classic are run through an online HPI check. On the HPI report, this vehicle shows no insurance database markers for damage or theft. It is currently not covered by a finance agreement.
UK-registered cars and motorbikes on Car & Classic are run through an online HPI check. On the HPI report, this vehicle shows no insurance database markers for damage or theft. It is currently not covered by a finance agreement.
A non-refundable buyer’s deposit is payable on this item, refer to FAQs and T&Cs for the applicable percentage.
All bidding, buying and offers are subject to our Terms and Conditions.
