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DannoXYZ · November 27th, 2019, 11:20 AM

I’m trying to get firm figure on dry and wet weight. When it shows up at Indonesian dealers, I’m have our contact there check it out.

I wonder how they do two different power outputs? I suppose electronic solution would be easiest. Milder ignition-map on 45ps model? With DBW, you can just program it to not open throttle all the way!

Smaller engines typically have higher specific-output than larger ones. It’s based on ratio of valve-curtain area to cylinder volume. As you scale up in size, cylinder volume increases by cube-power (^3), however valve-curtain area only increase by square-power (^2). So larger and larger cylinders are choked more and more due to limited flow through valves.

That’s also how little engines can rev to 19-20K, they can actually flow that much air with same cam-specs. Bigger engines lose VE in high-end and shows dropping torque and power curve.

Compare late-‘80s to early-‘90s 250 inline-4s versus their bigger countreparts. They were getting around 45-bhp. That would be 180-bhp for litre-bike. No litre-bike would get 180-bhp for another 20-years. ZX10R finally got there in 2008. With modern advances in EFI , materials tech and oil, I don’t doubt it can get 60-bhp.

Weight is still concern...

November 27th, 2019, 11:20 AM	#65
DannoXYZ ninjette.org certified postwhore Name: AKA JacRyann Location: Mesa, AZ Join Date: Dec 2011 Motorcycle(s): CB125T CBR250R-MC19 CBR250RR-MC22 NSR350R-MC21 VF500F CBR600RR SFV650 VFR750F R1M ST1300PA Valkyrie-F6C Posts: A lot. MOTY - 2018, MOTM - Nov '17	I’m trying to get firm figure on dry and wet weight. When it shows up at Indonesian dealers, I’m have our contact there check it out. I wonder how they do two different power outputs? I suppose electronic solution would be easiest. Milder ignition-map on 45ps model? With DBW, you can just program it to not open throttle all the way! Smaller engines typically have higher specific-output than larger ones. It’s based on ratio of valve-curtain area to cylinder volume. As you scale up in size, cylinder volume increases by cube-power (^3), however valve-curtain area only increase by square-power (^2). So larger and larger cylinders are choked more and more due to limited flow through valves. That’s also how little engines can rev to 19-20K, they can actually flow that much air with same cam-specs. Bigger engines lose VE in high-end and shows dropping torque and power curve. Compare late-‘80s to early-‘90s 250 inline-4s versus their bigger countreparts. They were getting around 45-bhp. That would be 180-bhp for litre-bike. No litre-bike would get 180-bhp for another 20-years. ZX10R finally got there in 2008. With modern advances in EFI , materials tech and oil, I don’t doubt it can get 60-bhp. Weight is still concern...