We now give the graphic relative to the Jumps/Losses Between Gears (%) for the Yamaha RD 500 V4 1985':

As we can see through the Graph "Jumps Between Gears (%) Yamaha RD 500 V4 1985' ", that the gearbox is appropriate for high speed bikes since the losses between gears are very closed, specialy between 5th and 6th gear with only 8.97% of loss. This gearbox purpose is good, very well spaced out between gears, for good use on low-mid ranges and the low loss in the last 2 gears make it for the high-revs.
Now we're going to present the thematic of the Real Velocities in Each Gear, also comparing the stock version and the actual one. Relatively to the top speed, it's necessary to have in count some aspects:

Using trigonometry, more precisely, the " Pitagoras Theorem ", we can calculate a very important index, and at the same time, interesting, because it explains if an engine is prepared for Motocross/Enduro or if it has a GP source.
As we can see, the conclusion we get is that the Yamaha RD 500 V4 with the actual engine tuning possesses an ConRod-Crankshaft Attack Angle of 75.35º, this value is very near the average presented by many MotoGP/Velocity/roadrace engines.

Values rounding 75.5º - 76.5º favour the high rotation regime, with short power and high bands, besides reducing the friction piston-cylinder (and from there more durability), confer one superior easiness in effecting greaters regimes of rotation and more keeping them of untied form and without effort during more time.

We are before the phenomena of Leverage: the longest the part that makes the effort, the more the force is necessary to effect the "work" in question, that's why we say that it possesses less Leverage.

But there is a point on the RPM range of revy engines, where this process gets upside down, or in other words, we can get advantage of long conrods in roadracing high rpm engines (e.g.: Aprilia RSR 125 GP bike, with square engine and 115 mms conrod length and 13300 RPM (~24 m/s), with a short leverage index, factor that empoorless the low and midle RPM's but empowers the last 2000/3000 RPM and get them quicker.