gas 4 strokes
#4
Join Date: Dec 2006
Location: ToowoombaQLD, AUSTRALIA
Posts: 1,026
Likes: 0
Received 17 Likes
on
15 Posts
RE: gas 4 strokes
ORIGINAL: vatechguy3
Surprised there isn't more interest in these engines.
Aren't they a drop in replacement for a ys setup??
Tony
Surprised there isn't more interest in these engines.
Aren't they a drop in replacement for a ys setup??
Tony
Being petrol/gas and non-supercharged you're giving away power to weight right off the bat, but that aside if the F3A rules drift towards a take-off weight rather than an empty weight then I could see petrol 4-strokes becomming a viable option. I just hope OS is dipping their toes in the water and consider bringing out some proper sized 4-stroke twins for IMAC.
#5
Senior Member
RE: gas 4 strokes
ORIGINAL: vatechguy3
Surprised there isn't more interest in these engines.
Aren't they a drop in replacement for a ys setup??
Tony
Surprised there isn't more interest in these engines.
Aren't they a drop in replacement for a ys setup??
Tony
Weight is listed at a hair under 3 lbs (1300g) just for the engine. Add CDI and exhaust system weight and you're in the 3 1/2 lb area, maybe more
Power is not really close to the piped OS GT33 2 stroke or the YS175 4 stroke. It turns 19x8 prop in the mid 6's from one account. Total weight for the OS GT33 isless than3 lbs, (also true for the YS175), a huge difference.
Sound or noise, well, the piped GT33 is slightly quieter than the YS175 turning the same prop (at higher rpm). I have heard the OS40cc run but it's hard to compare sound levels. Noise is not objectionable and I'd bet if it was fitted with Hatori stuff, it would be even quieter. Bottom line, 4 stroke gasoline needs considerable development to become viable in pattern, while the GT33 is already there....