I thought this sub might like some of the photos I took in pit lane at the Valencia test. It's quite illuminating to see the bikes with the fairings (at least partially) off and the mechanics working on them. Here are two photos of Yamaha's V4, and one of their inline four for comparison.

The first photo shows one of Alex Rins' mechanics carrying the fuel tank for the V4 ready to put it in place. The bulk of it sits below the rider's seat, with part that comes up and over underneath the tank cover.

The switch to a V4 engine has forced Yamaha to redesign and move everything. A rearward bank of cylinders means they have had to redesign the fuel tank.

There's now a section which sits above the airbox, a lot like the Ducati tank. You can see that the bulk of the fuel tank still sits beneath the seat.

Another sign that things have been reorganized is visible in the tail. With the seat section removed, you can see that the ECU is located there, but the rest is empty.

On the inline four, the ride-height device hydraulic system is located in that section.

Second photo:  
Here's the tank fitted on the V4. You can see how the top of the tank sits above the airbox. If you look closely, just in front of the tank, there's a black pressurized gas bottle.

The tank has a sticker with "9kg" on, which tells you how much fuel is in the tank.

At the front, you get a much better view of the pressurized gas bottle, with a regulator on the end. This is almost certainly the bottle used for the pneumatic valves.

Zoom in and you can see the air box below the tank.

The third photo shows the inline four. In the tail section, you can see the hydraulic lines, cables, and cylinders which activate the ride-height device. This is somewhere else on the V4.

This is what I mean when I try to explain just what an impact the switch from an inline four to a V4 has had. Everything has had to be moved to accommodate the new engine layout.



The Yamaha V4 fuel tank, and how it shows the work Yamaha still have left to do