MP2/YS91/8.18 - powerband

[Knud Pedersen DENMARK]

Hi

At what RPM would the MP2 produce most power together with the YS91?

Today I fly my Fury Extreme (8.18) at:
Idleup1 = 14500/1773 rpm
Idleup2 = 14750/1803 rpm

The engine produce good power, but I wonder if should try a higher RPM...
Nigel Brown is 16126/1950 on 8.27/Hatori 18/Synergy
But would this Rpm be outside the MP2 powerband?

PS: before my OS91PS i did fly with YS91/Hatori Sb16FH/8.45....but I would like a higher RPM on the rotor....
On Curtis homepage, he have written that 8.2 and about 1830-1850 with the YS91/MP2.......he also write that with the 8.45 it will not produce as much power as the 8.18....


ChopperKnud

[G MAN]

The YS will run better at the higher RPM with the muscle pipe,we have a guy flying an Avant with 8.08 and a YS 91 with a 1850 headspeed and it works just great.I would say 1850 to 1900 will work graet wiyh muscle pipe and YS.DOUG

[DebianDog]

I was just reading where Gordie Mead said (Rodney and Beast confirmed that) 8.4x is the ratio you want with the YS90. But unless you are a 3D master 8.1x will do for loops and rolls.

Not sure how much one pipe to another makes n the gear ratio.

[G MAN]

It really depends on the headspeed you want to run,if you want to run 1850 or 1900 a 8.18 or 8.08 would be a better choice. the YS is really timed for higher engine RPM.