QUOTE(blackbox14 @ Jul 9 2020, 11:49 AM)
Check Youtube for z400 dyno and I believe it's the TST industries dyno run that sums it up. I think the bike generally just doesn't need to be revved as high as the ninja and that makes it easier and more fun to ride.
As for cooling, in my experience the nakeds are better. Maybe because in city traffic I don't move at a constant pace that the channel in and draw out ability provided by the fairings is minimized. My ninja is fine when on the highway but in slower traffic the fairings stop the heat from radiating out, which is good for me but not so fun for the engine.
The TST industries showed higher torque and hp on its dyno compared to motorcycle_com and cycleworld. But, the curves looked similar than what other dyno's got. No comment on this one, but I would say the engines and gearing are the same. I cannot verify those claims, but I would not conclude Z and Ninja are different engine tunes.As for cooling, in my experience the nakeds are better. Maybe because in city traffic I don't move at a constant pace that the channel in and draw out ability provided by the fairings is minimized. My ninja is fine when on the highway but in slower traffic the fairings stop the heat from radiating out, which is good for me but not so fun for the engine.
Searching the dyno charts, particularly the torque one, the clear distinction Z400 against RC390 is 4~5.5k RPM. Associating this to D400, I think the D400 can be made faster by changing the sprockets based on rider's preference.
For highway cruising speed at 110kmh, D400 will be operating past its peak torque RPM, hence very inefficient.
For Z400, it is right before peak torque RPM, which is great if you need to overtake something and do so without dropping to 5th.
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