Gen 2 Engine Development begins

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mngforce

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More scanning work. Getting ready for a CAD-intensive rest of the month
 

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mngforce

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Crunching numbers. Found some interesting fun facts:

HP/Liter: the stock engine is only about 119 HP/Liter. MotoGP engines produce 250+ HP/Liter and modern showroom liter bikes produce more than 200 HP/Liter. I have personally achieved 232 HP/Liter. The engine configuration I am proposing will only be producing a very modest 162.45 HP/Liter at 300 HP. Very reasonable.

the stock port is lazy (too big) for the stock engine configuration. Target mach numbers for the tightest portion of the port are Mach 0.60~0.65. The stock port is only mach 0.54. The port restriction increases speed to mach 0.65 in the engine layout I’m proposing. Should prove to be quite responsive for street riding.

A very efficient NA race engine should produce BMEP numbers of 200+psi. The stock engine is a respectable 172psi. The engine I am proposing comes in at 200psi. Again, very reasonable.

the stock engine places loads of nearly 4,000 lbs on the connecting rods andcrank. The engine I am proposing will only increase this by approximately 150 lbs with much stronger rods and a much improved valvetrain. This is with a new rev limit of 10,550. This Rev limit has been proven already so I know even a stock lower end (crank & rods), as well as the stock valvetrain, can handle it.

By the numbers, the proposed engine should easily and reasonably handle the 300 HP target.
 

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mngforce

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Sorry for the delays. I had a major spine surgery a couple weeks ago. But, I’m back to business. On the flowbench as of today. I use dayglo paint and a black light to “see” the airflow
 

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mngforce

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Glad to see you are back at it. Was just wondering when we would get an update.
“Back at it”. LOL. Nice pun there. Non-intended I’m sure 😝

the flow testing will take a long long time for sure.
 

mngforce

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What are you looking for in the paint to see the airflow?
The paint shows me the stability and trajectory of the airflow (or more accurately the fuel flow). It can show turbulence and shrouding, which gives me direction as to where I can work to improve the ports. In the end, you want the best, most complete charge in the cylinder when it's time to fire the spark plug.
 

calibeary

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Thanks , just trying to understand what is going on in the video and pics. Glad to hear you are back at it . I hope your back is getting better. Back pain SUCKS !!!!
 

VmaXXX

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Not sure there's a correct answer so opinions are welcome.
Why wouldn't Yamaha have incorporated these improvements when the gen 2 was being engineered? Weren't these technologies available in years leading up to 2009?
If they'd released the gen 2 as a 300hp bike it would've been a shot heard 'round the world. I imagine it would've garnished the cover of every cycle mag and headlined every motoshow.
 

mngforce

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Not sure there's a correct answer so opinions are welcome.
Why wouldn't Yamaha have incorporated these improvements when the gen 2 was being engineered? Weren't these technologies available in years leading up to 2009?
If they'd released the gen 2 as a 300hp bike it would've been a shot heard 'round the world. I imagine it would've garnished the cover of every cycle mag and headlined every motoshow.
cost. It’s always down to cost. It will take money to get it from 200 to 300. Lots of development time for sure. Then lots of attention to details they cannot control during mfg. I was the Quality Engineer for Kawasaki for several years. Fractions of pennies mattered. Then, I was a Development Engineer in IndyCar. Expensive HP. Very expensive.
So…COST
 

VmaXXX

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cost. It’s always down to cost. It will take money to get it from 200 to 300. Lots of development time for sure. Then lots of attention to details they cannot control during mfg. I was the Quality Engineer for Kawasaki for several years. Fractions of pennies mattered. Then, I was a Development Engineer in IndyCar. Expensive HP. Very expensive.
So…COST
Presumably the sale price
cost. It’s always down to cost. It will take money to get it from 200 to 300. Lots of development time for sure. Then lots of attention to details they cannot control during mfg. I was the Quality Engineer for Kawasaki for several years. Fractions of pennies mattered. Then, I was a Development Engineer in IndyCar. Expensive HP. Very expensive.
So…COST
I'd not considered the challenge of controlling the tweaked tolerances during mass production. That makes complete sense. Thank you sir.
 

mngforce

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Presumably the sale price

I'd not considered the challenge of controlling the tweaked tolerances during mass production. That makes complete sense. Thank you sir.
Exactly. The mfg cost controls the sale price. It was already expensive. So it would be a $25k production bike otherwise. I’ll bet it still would have sold. But not as many units.
Sometimes the bean-counters kill tbe engineer’s dreams before they’ve even been put on paper
 
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