Okay, going to take a stab at this. One, your bike makes 46% more power than the Nighthawk with only a 6% bump in displacement (ish). It weighs ever so slightly more, only really applicable during acceleration.
The bike is setup to encourage higher speed travel, which increases drag and increases fuel consumption. It probably is /much/ cleaner at the tail pipe than the performance tuned Nighthawk. The tradeoffs of emissions cleanup means you end up burning a bit more fuel to have less emissions at the pipe. Odd, counter-intuitive thought, but it's true (for most things. There are diminishing returns). The big one that's a PITA to tame is the NOx/PM relationship: if you want less NOx, you have to cool the chamber, usually by adding more fuel to make a slightly rich condition. Richer mixtures make more PM. Leaning the mixture to reduce PM increases NOx, but richening makes more PM... gah! Of course, richening the mixture also increases CO and HC in gasoline engines. You admit that the computer isn't well matched to the bike on your model year; this probably impacts mileage as well. I imagine if your VFR had an engine that power-matched the Nighthawk instead of roughly matching it in displacement, your mileage would probably go up significantly. Takes gas to make Whee, after all. :D -Kurt On Thu, Oct 6, 2011 at 11:13 PM, Allen Thomas <althomas...@gmail.com> wrote: > Yea a 2003 VFR800, a little over 500LBS with 110HP. I really like the bike, > the power is about perfect, but the delivery of it is not so much. It can > put you in a scary situation if your not careful, but it doesn't have so > much power that it surprises you, just don't crank it to the stops in 1st > gear or it will flip upside down. (there is a youtube video of some dumbass) > It has decent torque, but you really need to keep it above 4K, 5k is the > best cruising RPM. The power doesn't start to really take off until 6K and > when it hits VTEC at 7.5K it feels like you suddenly got a second motor. It > is a little hard to drive in the 30-40 MPH range since it puts you in either > too low of a gear so the bike is snatchy, or you are lugging the engine and > have no power. 50+ is fine, don't think of using 6th gear unless you are > doing over 70 (more like 85+). If you are interested in one get a later > model than mine, the early ones have a particularilly bad fuel > mapping/computer that exacerbates the snatchyness of the throttle and the > VTEC transition, They changed out the computer on the 2005 and later models. > Mine takes some finese with the throttle and clutch when in first gear, > especially downshifting for a really tight turn. It's not a good beginner > bike. Also there is no rebound adjustment on the forks and it really could > use it, so I plan to do what just about every other VFR owner does and get > some gold valves. Things I love about it is it has over 200 mile range, the > power, the handling, the brakes are fantastic, the ergonomics are great > especially for a tall guy like me, the VTEC kick in the pants, and the sound > of that V4 is such sweet music. > > > > On Thu, Oct 6, 2011 at 10:47 PM, Kurt Nolte <vturbine.po...@gmail.com>wrote: > >> Allen: VFR 800cc? Weight? Power? >> >> The huge allure for me to EFI is the "hands off" nature of most EFI setups >> and it's adaptability. >> >> -Kurt >> >> On Thu, Oct 6, 2011 at 10:44 PM, Allen Thomas <althomas...@gmail.com>wrote: >> >>> I think the big issue is that people generally don't know how to tune a >>> carb anymore. My almost 30 year old brother has never owned a carburated >>> vehicle. My VFR with its pre and post cat O2 sensors and computer that uses >>> them to dynamically meter fuel during cruise only gets marginally better gas >>> mileage over the 750NH 1-2 MPG which is jetted and tuned for best >>> performance. >>> On Thu, Oct 6, 2011 at 10:28 PM, James O'Gorman <aspor...@gmail.com>wrote: >>> >>>> starting a new thread for this one... >>>> So let's say you have a well-tuned carburated engine, then you switch it >>>> to have tuned-port injection (since I would think that would be the most >>>> realistic swap.) >>>> >>>> How would mileage compare? >>>> >>>> I know that FI has some benefits such as on cold-starts, but I'm pretty >>>> sure that 'over all' FI in and of itself only provides marginally better >>>> fuel mileage. >>>> >>>> I know that mileage isn't the only concern when it comes to total >>>> environmental impact, but for the sake of this thread that's all I'm asking >>>> about. >>>> >>>> ...cause I'm not convinced that (well-tuned) carbs versus FI will >>>> make-or-break a mileage comparison. >>>> >>>> >>>> -- >>>> You received this message because you are subscribed to the Google >>>> Groups "Nighthawk Motorcycle Lovers!" group. >>>> To post to this group, send email to nighthawk_lovers@googlegroups.com. >>>> To unsubscribe from this group, send email to >>>> nighthawk_lovers+unsubscr...@googlegroups.com. >>>> For more options, visit this group at >>>> http://groups.google.com/group/nighthawk_lovers?hl=en. >>>> >>>> >>> -- >>> You received this message because you are subscribed to the Google Groups >>> "Nighthawk Motorcycle Lovers!" group. >>> To post to this group, send email to nighthawk_lovers@googlegroups.com. >>> To unsubscribe from this group, send email to >>> nighthawk_lovers+unsubscr...@googlegroups.com. >>> For more options, visit this group at >>> http://groups.google.com/group/nighthawk_lovers?hl=en. >>> >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Nighthawk Motorcycle Lovers!" group. >> To post to this group, send email to nighthawk_lovers@googlegroups.com. >> To unsubscribe from this group, send email to >> nighthawk_lovers+unsubscr...@googlegroups.com. >> For more options, visit this group at >> http://groups.google.com/group/nighthawk_lovers?hl=en. >> > > -- > You received this message because you are subscribed to the Google Groups > "Nighthawk Motorcycle Lovers!" group. > To post to this group, send email to nighthawk_lovers@googlegroups.com. > To unsubscribe from this group, send email to > nighthawk_lovers+unsubscr...@googlegroups.com. > For more options, visit this group at > http://groups.google.com/group/nighthawk_lovers?hl=en. > -- You received this message because you are subscribed to the Google Groups "Nighthawk Motorcycle Lovers!" group. 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