He lost his drive a couple seasons ago when he blew the 80 whatever it was points lead. Kids! ain't he ....
Quartararo Extends Contract With Yamaha Through 2026
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With the engines being set at the beginning of the season different exhaust systems give them the ability to change the tuning of the engine a little. There’s a photo floating around showing how different Pedrosa’s exhaust system was to Marcus’s when they were teammates.
As to what that style of exhaust does, my armchair expertise doesn’t extend to that
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Usually the fourstroke exhaust trying to copy what a twostroke exhaust can do. Which is Improving the amount of air/fuel mixture that gets into the cylinder. At fourstrokes they try to create a little vacuum through the interference of the exhaust pipes of different cylinders, which sucks more mixture in, whereas at twostrokes every cylinder has its own unique exhaust pipe shaped in a specific way so that it rebounds the exhausted gas to push back in unburned fuel that otherwise would have escaped through the open exhaust port in the compression phase
I agree that is the way Two stroke exhaust works, but the four stroke doesn’t need other cylinders to work, a single cylinder uses it’s own exhaust pipe to pass a negative pressure wave across to the inlet tract, on over lap, to increase the cylinder fill.
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It’s not just the sound and smell from two-strokes that I miss, but also, the brutalist artistry of hand-made, artisanal,
one-off two stroke exhaust systems that were a marvel visually. Very bad-...… sexy.
one-off two stroke exhaust systems that were a marvel visually. Very bad-...… sexy.
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Four stroke uses the interference in the header
the vacuum created by one cylinders exhaust stroke sucks more mixture into the combustion chamber of the other cylinder by the headers being connected at a specific point
It’s like a soft turbo effect and may be in the range of 0.1 bar (i guess) of underpressure
the vacuum created by one cylinders exhaust stroke sucks more mixture into the combustion chamber of the other cylinder by the headers being connected at a specific point
It’s like a soft turbo effect and may be in the range of 0.1 bar (i guess) of underpressure
Yes my friend, that is the well publicised theory of the “Extractor effect”, unfortunately it is a myth.
If we look at what the difference in pressures are when it is suppose to happen, as you say there is a negative pressure in the pipe connected to the other cylinder, but when that cylinder’s exhaust valve opens it releases a pressure of about 65 to 70 psi of hot gas into the pipe. You can see what the effect of the small negative pressure in the pipe would have.
That pressure that you talk of, is the negative pressure that returns back up the pipe to the cylinder to pass through to produce a negative pressure in the inlet tract against the atmospheric pressure, increasing the inlet flow.
If we look at what the difference in pressures are when it is suppose to happen, as you say there is a negative pressure in the pipe connected to the other cylinder, but when that cylinder’s exhaust valve opens it releases a pressure of about 65 to 70 psi of hot gas into the pipe. You can see what the effect of the small negative pressure in the pipe would have.
That pressure that you talk of, is the negative pressure that returns back up the pipe to the cylinder to pass through to produce a negative pressure in the inlet tract against the atmospheric pressure, increasing the inlet flow.
Are we now pretending that Mir and Fabio are on the same level??
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Agreed, and it is precisely why 2 strokes have expansion chambers on their exhaust/s and 4 strokes do not.
Sometimes, there is no massive performance advantage with a design. It can just be rider preference. I seem to recall Rossi preferring a longer exhaust because it made the bike quieter.
There are more aliens in the paddock than you realize...they just happened to land on the wrong bikes or were not suited for the larger displacement.
Imo of course.
Quite a few top 250 riders fit this description.
Imo of course.
Quite a few top 250 riders fit this description.
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I am implying their careers are headed in the same direction but I think that was pretty obvious by reading my post. They most likely will both retire with the same amount of motogp championships though.
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Absolutely. Pedrosa dominated the lower classes but never sealed GP title. Stoner, by contrast, only got a customer bike for his rookie season and he ended up being far more successful in GP.
Slightly off topic, but I rate Mir over Rins. Mainly because the former was more consistent during their time at Suzuki. I agree about each not winning another title though
I’m haven’t compared anyone to anybody? I was just commenting in an attempt to help you, so no fruit required today thanks.
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OK, so reading past the sarcasm, you mean to tell me that, just because they both have 1 championship each, it means they are on the same level? Unless Fabio has drastic fall in skill level, he will be in much greater demand than Mir.
Or maybe I'm missing something
Or maybe I'm missing something
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