NoWingsAttached
Unobtainium Member
- Joined
- May 21, 2006
- Messages
- 4,871
- Location
- Columbia, SC
- Aircraft
- Air Command Tandem w/ Arrow 100hp; GyroBee w/ Hirth 65hp; Air Command Tandem w/ Yamaha 150hp
- Total Flight Time
- >350
The mating surface area of the stock YG4 taper shaft is 30mm dia X 34mm L x 1:10 taper = 3022 sq mm
The depth of the bore and therefore the mating surface of the Arrow gear bore is identical, as is the primary clutch on the Yamaha snowmobile.
On my first "Silent Drive" drive gear, which was intentionally jury rigged to get it into the air quickly for testing, the drive gear bore depth was only 26mm, so the end of the shaft had to be ground down so it wouldn't bottom out. Apparently there is a need to similarly clearance and cut down the Yamaha shaft from 34mm to 26mm to accommodate the installation of a Rotax C Box ( although I have no experience using this PSRU so I can't really speak to why it is necessary to do so) either with or without the RK400 clutch. I think it has something to do with a lack of clearance for the head of the shaft bolt which holds the shaft coupling in place.
The depth of the bore and therefore the mating surface of the Arrow gear bore is identical, as is the primary clutch on the Yamaha snowmobile.
On my first "Silent Drive" drive gear, which was intentionally jury rigged to get it into the air quickly for testing, the drive gear bore depth was only 26mm, so the end of the shaft had to be ground down so it wouldn't bottom out. Apparently there is a need to similarly clearance and cut down the Yamaha shaft from 34mm to 26mm to accommodate the installation of a Rotax C Box ( although I have no experience using this PSRU so I can't really speak to why it is necessary to do so) either with or without the RK400 clutch. I think it has something to do with a lack of clearance for the head of the shaft bolt which holds the shaft coupling in place.