Tri-ville Project

Inspired by the prototype made over one week-end at the Meriden factory in 1976 we fit a T150 Trident engine into an Oil in Frame Bonneville (and we give it a few sporting touches along the way).


Photo from David Minton’s book ‘The Return Of The Legend Triumph’.

The oil cooler in the T160 Tri-ville is definitely NOT in a position that would allow easy¬†Exhaust Valve clearance adjustment. A T150 engine with upright cylinders would be a much better solution and would look more appropriate in a Bonneville Frame; so follow the photo trail as things come together…..

Triumph Trident-Bonneville (Tri-ville) FrameFrame modifications to accept the T150 engine and increase oil capacity. Bonnevilles suffered from the 4 pint limitation of the Oil In Frame tank. The Trident would suffer even more so the filler point has been moved to the front of the tank to increase oil capacity.


Triumph Trident-Bonneville (Tri-ville) Fuel Tank Modifications

Fuel Tank modified to accommodate the relocated Oil Filler.


Triumph Bonneville-Trident (Tri-ville) Footpeg and Engine MountDrive Side Footpeg and Engine Plate modifications showing crossover shaft to convert Hydraulic Disk brake to LH Side.


Triumph Trident-Bonneville (Tri-ville) Brake ConversionTiming Side Footpeg mount preparing to adapt hydraulic disk brake to LH actuation.

One of the hold-ups on the engine side of things has been the lack of a serviceable crankshaft. Finally a NOS item has been sources on eBay and now safely shipped from the USA to our workshop in Australia.

T150 Trident Crankshaft

Bottom end assembly is now one step closer.

A mock-up engine has been fitted to the frame so the necessary fittings can be created. Head Steadies have now been produced based on standard T150 items.


The oil Cooler mounts have been tacked to the frame to test that the position is correct and will allow oil lines, fuel tank and exhaust pipes etc to fit comfortably.


The fuel tank has been modified to fit over the wider three cylinder engine.


The project is now on two wheels.


Gear Lever and Linkages now have been created and connected.

Left Foot Brake Pedal transfers activation to RHS located Master Cylinder.

RH Brake is retained with LH Brake Pedal.

to be continued……