Max Fuel Efficient speed for CVT

[CMF_david (2)]

I was trying to calculate the maximum theoretical speed at which the CVT would still be efficient.

Based on
1.a wheel circumference of 1700mm.
2.ratio of 0.498 (at transmission) (Haynes)
3. final ratio of 5.247 (Haynes)
4. 4000 rpm (apparently this is the most efficient as it gives the most torque from this 1.3 engine.

Based on this it appears the max efficient speed, before the rpm would have to increase above 4000rpm would be.

4000 / 0.498 / 5.247 x 1.7 = 1300m/min or 156km/h

This is mighty fast. Could someone point out where I am wrong as I know my micra is flat out going that fast?

I'm a bit suspicious about including the 0.498 ratio, but I don't quite understand the meaning of the ratio's in Haynes.
If it was excluded it would give a sedate 80km/h which seems more likely, as this is when my rpm seems to start to need to increase in order to maintain a higher speed on the flat.

Also, Does anyone have an efficiency curve of the engine as the rpm increases?

 

[CMF_nz_aj]

Most efficient rpm should be at max torque, in the case of the CG13DE 4400rpm. rpm's above this will be less efficient.
On top of this, is wind resistance & rolling resistance which increases exponentially with speed. I don't know what the Cv & frontal area of the K11 is but this efect will limit the most efficient speed to well below the speed that 4400rpm will give.
Most likely the mose efficient speed will be somewhere aroun 80km/hr.