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Yamaha Genesis (YG) Engine

Gearbox Mounting Adapters

Mohawk Adapters utilize the stock Yamaha crank case cover in its perfect factory design which prevents oil blow-out from the breather in steep descent on tractor fixed wing aircraft and in climb in all other pusher-type configurations, FW or gyroplane.  We have seen our competitors' adapters, which eliminate the stock crank case cover, cause oil to blow out of the breather on several gyroplanes during climb.  
Engine Type:  Adapter Order ID
YG4    APEX:  GTI  $1095.00 
           RX1:  GTA $1095.00
YG3      All:  GTB $ 650.00
YG2 Phazer: GTC  $1095.00
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subject to change without notice 
Gearbox Options, add "-XXX"
MAC AK7:         -AK7
AirTrikes SPG4:  -SPG
Tango SP:          -TSP
Rotax C:            -RTX
Simonini C:       -SMC
Arrow:             -ARW
Hirth:               -HRT
Other:              -TBD
Apex GTI-RTX adapter with Rotax C PSRU mounted
This kit was shipped to Steve Henry for installation on the Wild West Highlander "Yee Haw 6" in 2017 and was available for inspection at Oshkosh 2018.  This was the first successful Yamaha APEX adapter ever installed by anyone, anywhere in the world. In 2018, MAC added a precision aligning ring to the GTI-RTX adapter which snugly fits inside the gearbox housing, insuring a perfect alignment to within +/-0.0005" tolerance specs, assuring the best possible wear characteristics for the shaft connection (either clutch or flex coupler), engine countershaft bearings, and gearbox.

Yamaha RX1 with GTA-Arrow Adapter
This GTA-ARW adapter is the world's first Yamaha RX1 conversion kit ever fabricated and successfully flown, in 2012.  The Arrow gearbox has an internal sprag clutch and steel alignment ring for precision mounting.  The taper-bore drive gear attaches directly to the YG4 countershaft PTO, and although the internal moving parts are twice as big as Rotax C PSRU's, the overall length of the installed power plant is nearly identical to the that of the Rotax C, making this an ideal unit for some of the shorter fixed wing nose cowls.
GTA-AK7 adapter for RX1 and MAC AK7 gearbox
MAC AK7 gearbox mounted to the adapter and crank case cover (CCV), with a countershaft installed to show how everything fits together.  The stock YG4 aligning pin pockets on the  CCV are precision milled through the top of the pockets, and mate to pockets in the adapter collar.  M8 x 30mm pins align the engine, CCV and collar together.  In line with these pins are a second set of M8 x 16mm pins that align the universal collar to the adapter plate milled for the type of gearbox to be used.  The CCV, collar and plate can be TIG welded together to form a single unit upon request, but we have not found this necessary.  Even after an unfortunate prop strike, the parts proved to remain intact and perfectly aligned, and the unit was continued to be flown.
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