Motorcycle specifications BimotaTESI 1D 851 1992 A sportswoman's thesis

The idea was born in the minds of 2 students from Bologna. 10 years of research and development later, Bimota presents a sports bike that goes even further than the ELF. Like the ELF, its front end does without telescopic forks, except that the bike presented here is a road version. The ELF, on the other hand, has never left the racetrack. The Tesi 1D is therefore a small revolution in the world of sports bikes. Seen from afar, you'd have no idea of the technology it contains. Its design is very much in the Bimota tradition, with an imposing fairing that conceals almost everything. However, it doesn't take long to realize that the bike has not 1 but 2 swingarms. So, how does it work?

Well, hang on, this isn't going to be easy. The half-handlebars are connected to 2 conventional tees, giving a position similar to that of a conventional motorcycle. Now it gets complicated: the tees act on a set of linkages, which rotate a short steering column fixed to the left of the machine. This allows the steering angle to be varied. The underside of the column operates another linkage that turns the wheel via an axle and two tapered bearings fixed in the steering hub. Complicated? Just think... the technical file is close to incomprehensible. But it works.
The rest of the chassis is made up of 2 alloy plates where the swingarms are fixed, and a tubular trellis for the upper part (where the seat, fuel tank, cladding, etc. are fixed). The structure uses the engine as a stiffener. What's this motor anyway?
Well, you can use 2 of them. The Tesi is built with 2 versions of the liquid twin of the Ducati 851. One is the standard 851 cm3 version, which has been upgraded with a set of dual injectors, a new exhaust and different electronics. The other version, extensively revised by Bimota, is distinguished by its displacement, which has been increased to 904 cm3 by increasing the stroke and bore. These twins develop 103 and 113 hp respectively. The 904 delivers more torque and power at lower revs than the 851.

Once on board, the rider is installed as on any sports car. There's no disorientation here, except that you can't see the forks and the instrument panel is completely electronic. Engine rpm, speed, various gauges, everything is displayed digitally (N.R.: A speedometer unit reminiscent of that on the Honda VTR SP-1, less sophisticated but still 10 years ahead of its time). The Ducat twin expresses itself violently through Bimota exhausts. All good stuff! The Tesi's handling is close to that of a conventional sports bike (the numerous feeling problems encountered on the proto seem to have been resolved), but the Italian is extraordinarily sensitive to settings. 2 notches too many or too few and the machine obeys you askew. A crucial factor. You might as well heed the factory's advice and prepare your shock absorbers with the utmost care. Once set up, the 1D's stability and handling in corners are remarkable. The front end's greatest asset is its fantastic braking potential. The Brembo system is already highly effective, and is further optimized by the very special configuration of the front end. You can grab the brakes much later and slam into them like crazy. As a result, the bike is able to take on very muscular corner entries, and it's still possible to keep the brakes on in the bend without everything going haywire.

Once out of the virolo, it's time to get the watts talking. Up to mid-rpm, there's no real difference between the 2 distillers. Once past that point, the 906 takes the lead, logically demonstrating greater efficiency and more potency. This surplus of vitamins will also be trickier to manage than on the 851. This will enable future buyers to choose between a sporty and a very sporty version.

There's a new sportbike every year (or almost every year). But a new type of chassis for a motorcycle is much rarer. Once again, the Rimini factory proves its know-how and willingness to innovate, even if this means a machine requiring a mortgage, increased technical maintenance and the need to be very careful with settings.