My friends 860 great power zero issues..remember 860 has nice separate insanely stout jugs custom made.
you know I'm starting to think the best think one can do is just build a nice ported carbed BB 800, get a pipe and plate from brad and bolt it in, zero issues 175 hp,premix...done deal
On another side note the only reason to use a short rod ratio is when a motor has a very big intake port area (ie pro stock) the short rod violent movement and "jerk" at tdc-bdc will in fact get the air moving much quicker through the port while the engine is moving up in rpm, yes the peak power will suffer as the rod will not "dwell" as long at TDC but in a drag engine we will trade off this for more rapid air movement while running the huge port. AND the fact that i'll take the motor apart every 20 runs or so and freshin it up. It has been found that in a pumping cycle of a engine if you run big port and 1"+ valve lift it will in fact injest a bigger "chunk" of air with a short rod ratio. But of course downside is very short life of rings,bore and ringseal issues. The friction is reduced by the use of a very short skirt piston, think "pancake on a stick" lol again, only has to last a weekend before rebuild.
Gut feeling is dumb engineers tried to make motor as light as possible and more compact and just plain old screwed the pooch bigtime
you know I'm starting to think the best think one can do is just build a nice ported carbed BB 800, get a pipe and plate from brad and bolt it in, zero issues 175 hp,premix...done deal
On another side note the only reason to use a short rod ratio is when a motor has a very big intake port area (ie pro stock) the short rod violent movement and "jerk" at tdc-bdc will in fact get the air moving much quicker through the port while the engine is moving up in rpm, yes the peak power will suffer as the rod will not "dwell" as long at TDC but in a drag engine we will trade off this for more rapid air movement while running the huge port. AND the fact that i'll take the motor apart every 20 runs or so and freshin it up. It has been found that in a pumping cycle of a engine if you run big port and 1"+ valve lift it will in fact injest a bigger "chunk" of air with a short rod ratio. But of course downside is very short life of rings,bore and ringseal issues. The friction is reduced by the use of a very short skirt piston, think "pancake on a stick" lol again, only has to last a weekend before rebuild.
Gut feeling is dumb engineers tried to make motor as light as possible and more compact and just plain old screwed the pooch bigtime