4 ms·

It would make them too heavy. Two stroke engines have a great power to weight ratio, which is pretty much the only reason that they are used.

burfog 8y ago
It's fine. Even my weed trimmer is 4-stroke. Aircraft engines, which really need to have a great power to weight ratio, are normally 4-stroke. For small things, the only place that seems to justify 2-stroke is a chainsaw. This is partly because weight matters much more, and partly because a chainsaw is held at many different angles. Oil flow in a 4-stroke engine is difficult when you can't rely on gravity going in any particular direction. Given that the whole point of a leaf blower engine is to move air, I have to wonder if the best solution might be a turbine.
- giardini 8y ago
  That's a great idea! Now if you'll just design an inexpensive turbine that won't fly apart catastrophically at 10,000-50,000 rpm, twist your hand off due to gyroscopic forces, and is easy-to-start w/o first spinning up to 5,000 rpm, we're set to go! Best bet: electric corded (120 Volts AC) leaf blowers: cheap, powerful, reliable, light and easy to maintain. No danger of battery fire/explosion due to abuse/age.
  - simcop2387 8y ago
    The startup issue might be mostly solved these days with cheap lithium batteries and brushless dc motors. That said you still have the turbine issue and the fact that it'll be much much louder.
ericd 8y ago
Not sure I buy that it would be too heavy, especially in the case of the backpack models.
- marcotaves 8y ago
  funny and curious I dont know about these big garden grass cutters, We dont have it in Brazil almost in the integrality , maybe fery few , but anyway even around the world I dont remember playing with this kind of machine, so, well...I read in Hackernews before that some people got their feet hurt riding those things If I am not mistaken and remember well design flaws... Is it a Diesel powered machine??? As Noisy and dirty and pollutant as an old obsolete type non-oil-free , I mean non-screw type , the kind with two cylinder pistons on top, probably as explosion chamber, and motriz energy transmitters compounded of barenaked unrailed conveyour belts (they convey energy) that, Well...cheap air compressors, you get it, yeah... design flaws all around kids and old people and even an horizontal wafer making type of toaster maker , a tostapane (italian) can have the design flaw if an old lady stick a rounded point knife to take her toast there and the metal conduces electricty from the not enoughly suficiently , maybe even uninsulated interior of the toastmaker trough the tool to the old ladys hands... talking about strictly home apliances and house machines, please, no double meanings , thanks And what a blowtorch is doing with an Motor explosion-based Engine near it??? I dont know, I am not an engineer , much less blowing torches engineer or any kind of blowcraft or blowork engineer, so...anyway... what about aceylene-oxigen blowtorches? I remember if not mistaken they dont need engines to run it , but I am no combustion coupled liquid fuel mixing engineer, or gas , by any matter, and by all matters... I am curiou what the DIesiel Polluttance Level of this machines you guys comment about in your comments, The European Union has some standards , named EURO2 (old and obsolete) EURO3 (maybe countries in Africa use it a lot , even the E2 still, so...)... right now maybe they are already on EURO6 version on validity at Europe as for now, I am not sure dont remember things so well, memory yeah... Diesel of trucks and other transport vehicles , generate heat and pollution... filters they need for diesel engines, good Filters...FIlters for noise too...a bird or squirrel feels unpleasant to hear such loud noises from these diesel engines, please... thanks
hinkley 8y ago
Someone was proposing a sleeve valve design to fix the weight problem, but that was years back (when blowers first hit the level of nuisance), so I’m assuming that didn’t pan out...

burfog 8y ago

It's fine. Even my weed trimmer is 4-stroke. Aircraft engines, which really need to have a great power to weight ratio, are normally 4-stroke. For small things, the only place that seems to justify 2-stroke is a chainsaw. This is partly because weight matters much more, and partly because a chainsaw is held at many different angles. Oil flow in a 4-stroke engine is difficult when you can't rely on gravity going in any particular direction. Given that the whole point of a leaf blower engine is to move air, I have to wonder if the best solution might be a turbine.

giardini 8y ago
That's a great idea! Now if you'll just design an inexpensive turbine that won't fly apart catastrophically at 10,000-50,000 rpm, twist your hand off due to gyroscopic forces, and is easy-to-start w/o first spinning up to 5,000 rpm, we're set to go! Best bet: electric corded (120 Volts AC) leaf blowers: cheap, powerful, reliable, light and easy to maintain. No danger of battery fire/explosion due to abuse/age.
- simcop2387 8y ago
  The startup issue might be mostly solved these days with cheap lithium batteries and brushless dc motors. That said you still have the turbine issue and the fact that it'll be much much louder.

ericd 8y ago

Not sure I buy that it would be too heavy, especially in the case of the backpack models.

marcotaves 8y ago
funny and curious I dont know about these big garden grass cutters, We dont have it in Brazil almost in the integrality , maybe fery few , but anyway even around the world I dont remember playing with this kind of machine, so, well...I read in Hackernews before that some people got their feet hurt riding those things If I am not mistaken and remember well design flaws... Is it a Diesel powered machine??? As Noisy and dirty and pollutant as an old obsolete type non-oil-free , I mean non-screw type , the kind with two cylinder pistons on top, probably as explosion chamber, and motriz energy transmitters compounded of barenaked unrailed conveyour belts (they convey energy) that, Well...cheap air compressors, you get it, yeah... design flaws all around kids and old people and even an horizontal wafer making type of toaster maker , a tostapane (italian) can have the design flaw if an old lady stick a rounded point knife to take her toast there and the metal conduces electricty from the not enoughly suficiently , maybe even uninsulated interior of the toastmaker trough the tool to the old ladys hands... talking about strictly home apliances and house machines, please, no double meanings , thanks And what a blowtorch is doing with an Motor explosion-based Engine near it??? I dont know, I am not an engineer , much less blowing torches engineer or any kind of blowcraft or blowork engineer, so...anyway... what about aceylene-oxigen blowtorches? I remember if not mistaken they dont need engines to run it , but I am no combustion coupled liquid fuel mixing engineer, or gas , by any matter, and by all matters... I am curiou what the DIesiel Polluttance Level of this machines you guys comment about in your comments, The European Union has some standards , named EURO2 (old and obsolete) EURO3 (maybe countries in Africa use it a lot , even the E2 still, so...)... right now maybe they are already on EURO6 version on validity at Europe as for now, I am not sure dont remember things so well, memory yeah... Diesel of trucks and other transport vehicles , generate heat and pollution... filters they need for diesel engines, good Filters...FIlters for noise too...a bird or squirrel feels unpleasant to hear such loud noises from these diesel engines, please... thanks

hinkley 8y ago

Someone was proposing a sleeve valve design to fix the weight problem, but that was years back (when blowers first hit the level of nuisance), so I’m assuming that didn’t pan out...