flatsides?
Damn they look familiar, XSeleven maybe?
"Thank-you for playing, but, no!" (answer to your first remark)
They could be used on many different bikes depending on the spacing and cables. In the 'old days,' actuation of the carbs was by one cable per carb, quite different than it is on our 1980's design bikes. Of course, now it's resistance/electronic throttle control, 'ride-by-wire.' It was a common thing to do to synch the carbs as the multiple throttle cables stretched. This was eliminated as a constant battle against going out-of-synch when the carbs were fastened together and used a common two-cable bellcrank to actuate the butterflies simultaneously.
Here's a flatslides bike. Of course, the flatslides weren't yet invented when this bike was made, not for road use. This is a pure street-racer, a 'Q-ship' which looks slapped-together and crude, but runs 9's. It's got +++displacement, head work, cams, a drag racing gearbox w/airshifter, lock-up clutch, sidewinder exhaust, electronic engine controls for drag-racing, etc.
Kenny Roberts racing the TZ700/750 two-stroke 4's in Grand Prix (and the notable Springfield IL flattracker) used Lectrons for carburetion which are still popular today for drag racing.