prop advice for 75cc moki petrol

[richard armstrong]

hi all

75 cc moki is going in a 50cc greenly tug prop size for pull not speed

looking at a 3 blade 22 x 10 or 22 x 12

need advice on best size for pull not speed for 2 blade or 3 blade

this will be a tow tug i want to be able to 4-6 m gliders

also dose anyone have a moki prop drill guide or can you still purchase?

i have check the prop size on the moki website

advice welcome

[Dave Wilshere]

22 x10 3 blade for pull.
If you can run a 2 blade clearance 24 x 10 or 25 x 10 2 blade
Pretty certain the prop pitch bolts is the same as DA/DLE 85-100

[richard armstrong]

22 x10 3 blade for pull.
If you can run a 2 blade clearance 24 x 10 or 25 x 10 2 blade
Pretty certain the prop pitch bolts is the same as DA/DLE 85-100

THANKS DAVE

see you soon i hope

[John Greenfield]

Richard
You will always get more "pull" with the correct size of 2 blade prop rather than a 3 blade. you say "50cc Greenley" but there has never been one that size, I assume you mean an SD Greenley, 88" span which was designed around a Zenoah 62. Built as per the plan there will be plenty of prop clearance for a 2 blade prop. I would suggest 24 x 10 for slippery glass gliders or 26 x 8 for slower draggy vintage types.

John

[richard armstrong]

Richard
You will always get more "pull" with the correct size of 2 blade prop rather than a 3 blade. you say "50cc Greenley" but there has never been one that size, I assume you mean an SD Greenley, 88" span which was designed around a Zenoah 62. Built as per the plan there will be plenty of prop clearance for a 2 blade prop. I would suggest 24 x 10 for slippery glass gliders or 26 x 8 for slower draggy vintage types.

John

the smallest of the greenley collection

i think is the 88" span with slight mod

i was thinking of the ground clearance i had issues

i am not putting the wire under cart on

i using fg one i pick up at a swap meet about 1.5 in shorter

did think about adding bigger wheels to compensate???

24 x 10 to 26 x 8 range

if i go 25 x 8 or 25 x 10 would be a compromise and work across the both glass gliders and vintage?

thank john

[John Greenfield]

the smallest of the greenley collection

i think is the 88" span with slight mod

i was thinking of the ground clearance i had issues

i am not putting the wire under cart on

i using fg one i pick up at a swap meet about 1.5 in shorter


Modified airframe, non-standard undercarriage and an engine well in excess of the 30 to 40cc it was designed for. It's clearly not a Greenley anymore.
FG undercarriage is heavier than the wire one, it will need extra internal structure in the fuselage to adequately attach it and larger wheels will be heavier and will cause more drag. All items that will clearly add weight and reduce performance !!!!!!
Why is it that people feel the need to modify a model that has been developed over more than 20 years and countless prototypes just to make it worse !!

Rant over.

John