I'd like to say a few things.
First off for the question that was asked. "Has any body tried a boost bottle on a whizzer 4 stroke,or do they only work on 2 stroke engines???
Bill b"
I'm not sure if anyone has tried one on a 4 stroke "wizzer" BUT if you get the size right, and your manifold is not already tuned well, then you can increase performance... ON A 4 STROKE. So there are some "if" "ands" and "buts"
but yes... it's possible that it will. The second part of my answer is that... most of the gain you will see form the bottle would be bottom range and a 4 stroke usually doesn't lack in that area.
"Hi, well, the boost bottle is strictly to "pulse" back into the cylinder increasing the charge in the head, on a 2-stroke. It will have no logical effect on a 4-stroke engine.
performance concepts are in most cases completely different."
Wrong in a few ways. The boost bottle does more than that. The scavenging of fuel and air was actually meant to make the engine work "normal" at low RPM and not to increase power. If you don't understand the inner workings of a carb then it won't help you to read the next part.
The problem in the intake is this. Air flows threw the intake tract as the engine demands it... ( 2 or 4 stroke ) then when the engine blocks the flow ( a valve or piston ) the momentum of the air causes a positive pressure to build on the engine side of the carb and intake manifold. At low RPM the air "bounces" back over the jet tube ( or whatever in the carb supplies fuel ) and draws out more fuel ... just as it did going in the first time. This causes the mixture at low rpm to be rich.
The bottle is simply a space for the pressure to relieve into so that it doesn't pass over the jet tube and cause the enriching problem. The size is important because the bottle will fill in a given time depending on it's size. For it to work properly it fills and starts to reverse and come back out just as your engine starts to demand another intake charge.
Other than that... performance concepts are the same ... more fuel and air = more power... till something gives or melts
"If you had read this stuff, one thing came out in the first page that the boost bottle PROBABLY (read WON'T) work on a reed-valve engine."
90 % of the boost bottle engines that I've seen, and that's more than a few, are reed valve. Reed valve has very little effect on an engine "needing" a boost bottle.
"Ok, now if the reed (in between the engine and carb) would stop the action of the bottle, what do you think might happen with our intake valve? A good running 4-stroke will NEVER sneeze into the carb. We also do not charge our crankcases with mix to run, we port gas mix directly above the piston."
If you've read any of what I've written then you know why this is wrong... It's correct that a 4 stroke won't "sneeze" back... but neither does a properly tuned 2 stroke AND as I have explained .... sneezing isn't the cause for the boost bottle being needed. More so the momentum of the air.
"In reality, there are very few similarities in 2-stroke and 4-stroke tuning and performance."
They are all the same ... just a different way of getting the same result. To make either engine run, and run well, you need proper fuel, air, compression, timing of intake and exhaust and ignition timing. Everything you need to make a 4 stroke work well you also need to make a 2 stroke work well.... it's just different ways of achieving those things.
"Hi, now for me, that makes sense, even tho that technology does not work on any valved engines,
Thanks,"
Again ... wrong. "valved engines do benefit from a bottle.... Many have.
If any of you don't believe what I'm saying then do some research outside of this forum. Tho I'm not cretin who "invented the idea" Yamaha popularized the bottle and has used it on MANY reed valve engines. It's been used on 4 strokes ( many British cars ) and multiple cyl engines as well as singles. Fuel injection and "proper" tuning of intake lengths and volume has made the bottle less popular these days but it still has it's place when used when it's needed.
Understanding how something works, in detail, is often the best way to maximize the benefit if any. For example... putting a turbo ( I know this is silly but a great example ) that flows 100 CFM on an engine that demands 150 CFM of air is only going to harm performance. If your intake pulse is tuned to work properly then a boost bottle will only harm performance.
I am passionate about problem solving and enjoy wrapping my head around the idea of what happens in an engine. Hope I haven't offended anyone.