A 100mpg quest

Discussion in 'OT Driven' started by AVengeance, Jul 9, 2009.

  1. AVengeance

    AVengeance Active Member

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    Okay, so I'm thinking about CBFryman's comments about how wind resistance is everything, and especially so at highway speeds. The vast majority of miles I'll be putting on my Ninja 250R is going to be at around 60mph. Right now, I'm at 61-63mpg.

    Can I make it to 100mpg?!? Anyone wanna place bets? Anyone wanna help with aerodynamics advice?

    I'll be making one mod at least every 1 month or 1000 miles thru autumn. I need to space them far enough apart to get a few fillups on them so I know what each change has done. I'll keep updating this post with new info.

    Mod 0: (because it's always ongoing): lightweight fasteners. To offset the increased weight from some of the mods, I'll be using Al and Ti fasteners wherever possible. I'll also replace small brackets with parts of my own design.

    Mod 1: rear fender skirts of my own design. These will help create somewhat of a "teardrop" shape out of the bike's tail area, where before it was just open. Alternative would be fender elim., which does nothing to cover the rear wheel.
    Tested, and is known good for about 2mpg.

    Mod 2: HotBodies GP windscreen. The GP windscreen is supposed to be 1" taller than stock (by that, the bubble shape is taller- the windscreen is not actually longer than stock), which should help push air over me, and make it possible to do Mod 2.5, a windscreen extension.

    Mod 2.5: windscreen extension of my own design. This v-shaped piece of .040" thick aluminum pushes the bolt holes for the windscreen about 3" from their original positions. since the windscreen is mounted diagonally, that's about 2" up and 2" back. I've mounted this on the bike as of 7/20 with my stock windscreen, to see what difference it makes by itself. The new windscreen will go on later this week.

    Mod 3: front airdam. This piece covers an exposed area of the bottom front of the bike (in front of the exhaust header), where it is now open (see pic below, and yes, I'll be painting it black). This will force some more air around the bike's smooth fairings that would otherwise go into the engine compartment and then under the bike, contributing to turbulence. It also should force slightly more air through the radiator that would otherwise just have blown under it.

    Mod 4: rear license plate vertical holder: made from lightweight aluminum, instead of heavy stamped steel like the stock piece. Takes up a smaller profile on the rear of the bike.


    Mod 5: new muffler and carb re-jet: before changing the gear ratio, I wanted to bump up the engine's power and efficiency. The OEM muffler from a '09 Ninja ZX6R is lightweight and made to flow gobs of air, so that's what I used. It's also reasonable attractive and fairly aerodynamic.
    [​IMG]

    Mod 6 - 4/2010: front sprocket, 15t (OEM is 14t). Bumping the final drive ratio by changing the front sprocket should put the engine at a slightly more comfortable RPM for better miles per gallon. Increasing sprocket diameter will also mean the chain has to flex slightly less, resulting in a tiny bit less power loss and chain wear.

    Mod 7 - 6/2010: front fender. after testing, I've decided to stick with the ZX14 fender. MPG is back up to just a hair over 70 now. The ZX14 fender has better coverage than the OEM 250R fender for improved aerodynamics.

    Mod 8: 39t rear sprocket. Smaller, lighter (aluminum alloy) rear sprocket, w/ 39 teeth vs the OEM 45 tooth version. Final drive ratio is changed even further, putting 5th gear where 6th gear was with just the 15t front and OEM rear sprockets. RPM @ highway cruising speed (62.5mph avg) is 6225. Potential top speed is 125.4mph (although without further power adders and/or aero improvements, I'd never see that kind of speed). With the stock setup, the same RPM would only produce 101.5mph!


    Mod x: lower the bike about 1" front and rear (RoaringToyz lowering links and handlebar spacers). Nothing "extreme", but just to get out of the air flow a little. The less frontal area, the better.

    Mod x: airbox removal and aftermarket filter install. Getting consistant reports of increased performance by removing the restrictive OEM airbox. If efficiency is increased, the gear ratio can be further changed by swapping to a smaller rear sprocket. A rejet would be required, which would likely decrease MPG until the gear ratio was adjusted

    Mod x: larger storage compartment to replace rear seat? This is a "maybe" item, based on the post by c0ldf1ame below. I'd need one of the Kawasaki rear seat cowls for the original mounting points, then I'd have to make a larger shape (from fiberglass or reinforced plastic) that would attach in the same manner. If the shape was an aerodynamic extension of my body on the bike, it would help aerodynamics. I've seen those "hypermiler" bikes with a huge piece on the back, and I ain't doin' that. It would be nice, though, to have a locking compartment big enough for a small bag of groceries, change of clothes, or my lunch box.

    Mod x: LED/ HID lighting. I recently replaced the tail lamp with LED, mostly because it lights up brighter and faster than an incandescent. This was done in conjunction with a brake light strobe, which automatically flashes my brake light 3 times before staying on solid. Increased saftey = win. Combined with other alternative lights, a drop in electrical load will free up engine power for motive work.

    Taking advice on what else I can do to get the air to slide around me. Not looking for a big damn race fairing or anything. It still should look (pretty much) like my bike.

    Mod 1 - rear fender skirts:

    [​IMG]


    Windscreen Extension (shown with OEM windscreen):


    [​IMG]


    [​IMG]
    front airdam, slides more air around the body that would wind up in the engine bay (terminates well below the radiator, though, so cooling is still sufficient).


    [​IMG]
    vertical license plate mount.
     
    Last edited: Jul 19, 2010
  2. c0ldf1ame

    c0ldf1ame New Member

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    maybe a rear hump on the tail where the passenger goes?
     
  3. GammaRadiation

    GammaRadiation Active Member

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    It's going to be hard to significantly improve your aerodynamics with out drastically changing the bike. Ideally, you'd make a raindrop shaped shell that goes around the bike and get it as low to the ground.

    You'll likely see the most improvements from gearing and engine improvements.

    A 60% increase in fuel economy is pretty hard.
     
  4. BlkDrgnZ28

    BlkDrgnZ28 OT Supporter

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    i'de like to see but don't think its gonna happen without a drastic change in body design
     
  5. bs2100

    bs2100 New Member

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    Find a really big hill.
     
  6. Junkie

    Junkie re-tarded OT Supporter

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    enclose the front wheel
     
  7. AVengeance

    AVengeance Active Member

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    I was wondering about some kind of "discs" to go over the wheels, or at least the front. Seems like the improvement from that would be pretty slight.

    Lower it? Yes, definately. Still need to get over speed bumps, but I can bring it a little closer to the ground. Not sure what else I can do about the front wheel, but it seems like there could be more fender around that wheel. I could make some kind of latching-on back seat replacement- a sort of "luggage box" that could be aerodynamically shaped. I don't want to drastically alter the bike's existing fairings, and I don't want it to look like a big dorkmobile. I don't expect 100mpg out of aero changes alone. Gearing, lowering, riding style and position, exhaust (lighter, closer to body, less restrictive), etc. I'll also be changing the brake lamp with LED, and the cluster lamps with LED. That's probably 30w I can replace with about 4w. Might not mean much in a car, but on a bike, that's less pull from the generator. Also looking into lower watt headlamp possibilities (I hear some HIDs are more efficient).

    We'll see.

    Oh, and something that won't much affect mileage - I installed a brake strobe for safety, so I don't have to tap the brake to flash it.
     
  8. GammaRadiation

    GammaRadiation Active Member

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    Good call on the LED's 30w is almost a 10th of a HP from the engine. Might not sound like much, but every bit counts especially on smaller motors.

    HID's are more efficient. I dont know much about bike bulbs but you can get more output from a 30w HID lamp than you can from a 60w halogen.

    I dont know what the aftermarket is like for the Ninja but try picking up an exhaust system and a hotter ignition.
     
  9. Vermincelli

    Vermincelli Banned

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    GET OFF MY LAWN!
    pull out the motor and get a diesel/biofuel motor. Army's KLR650 diesel already gets 100mpg.

    Seriously, you may end up gaining about 6-10mpg by adding all that but you're going to run into limitations from the engine itself. 100mpg has been reached with the 250 but you are going to sink some money into it to reach that or drive like an idiot doing those stupid hypermiler techniques.


    law of diminishing returns is in full play when it comes to motorcycles.
     
    Last edited: Jul 10, 2009
  10. mtnbikekid08

    mtnbikekid08 Aime-moi moins, mais aime-moi longtemps

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    If you had the money, you could probably get 100mpg out of a redesigned fairing alone.
    As for LED's, that won't do shit for you. Unless you are going to running 10,000 other things off the generator, don't expect LED's to do anything.
     
  11. GammaRadiation

    GammaRadiation Active Member

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    Not noticeable alone, but every bit of energy not being sucked from the motor will help.
     
  12. mtnbikekid08

    mtnbikekid08 Aime-moi moins, mais aime-moi longtemps

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    That generator is pulling power from the engine regardless of draw. It spins as the engine spins, and produces the same amount of power. It doesn't spin more if there is more draw, that is up to the voltage regulator to determine.
     
  13. GammaRadiation

    GammaRadiation Active Member

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    :ugh:
     
  14. AVengeance

    AVengeance Active Member

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    :ugh:

    Apparently, you don't know much about electricity, or electric motors and generators. I do, and you can, too. Lesseee.... unhook the belt from a generator in a car, unhook the battery, and spin the generator by hand. Spins pretty easy, right? Now, hook it up to a car battery that reads about 10.8v and spin it by hand. What, you say? You can't make it spin? Okay, hook up a hand crank to it, and try again. Oh really? You can barely turn it, and it goes thump thump thump with invisible resistance?

    Look, you just learned something!

    Okay, so here's the deal. You're right in saying the generator will spin at the same SPEED (since the generator speed is based on engine speed and not electrical load), but if there is less electrical load, there will be less RESISTANCE to the rotation. In a 300hp car, a couple LED lights would be unrecognizable. In a 20hp motorcycle, I bet that difference would be calculable. Not to mention that LEDs light up faster and can be strobed (the safety alone is worth an LED brake light). I may also add LED DRLs to replace the daytime function of the headlamp. That's just a thought at this point, though.

    The Eliminator 125 gets damn near 100mpg right off the showroom floor, with absolutely terrible aerodynamics. Surely I can get near there in the EX250 with some weight redux, aero improvements, decent driving style, etc. I've been designing parts for race cars for over a decade, and racing with what I build. The same concepts apply, regardless of the goal (handling, speed, accelleration, economy, whatever).

    Kawasaki makes a race generator, but they say it won't handle a full potential load (I'm guessing, both headlamps + brake + a flasher going at once). Maybe with LEDs everywhere except the headlamps (including the gauage cluster) I'd be able to run that generator. :dunno:
     
  15. Hahawhat?

    Hahawhat? New Member

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    Try shifting at lower rpms and driving for longer distances with less stop and go situations....
     
  16. mtnbikekid08

    mtnbikekid08 Aime-moi moins, mais aime-moi longtemps

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    That resistance is from the battery, not the lights retard. Put a smaller battery, voltage-wise, in and it will be easier to turn. Why not try figuring a way to use a 6-volt battery instead? You won't be saving anything by switching to LED's.
     
  17. pew pew pew

    pew pew pew OT Supporter

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    start with fuel injection :rofl:
     
  18. AVengeance

    AVengeance Active Member

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    Oh, dear. Look, when I first dropped into this subforum, I had equal respect for everyone in it, including you.

    Over time, though, it has become apparent that

    YOU DON'T KNOW JACK
    A discharged battery is an electrical load, just as the lights are an electrical load. Using a discharged battery would be an easy way to prove the point, and was an experiment you could easily have conducted yourself.

    You were WRONG about the OEM tires size on my bike. You were wrong about numerous other things. You're wrong about this. Please, please, with all due respect, LEARN ABOUT WHAT YOU'RE TALKING ABOUT BEFORE YOU TALK ABOUT IT.
     
    Last edited: Aug 21, 2009
  19. AVengeance

    AVengeance Active Member

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    Most driving is already highway driving. I did choose a route that has a little lower "typical speed".

    As far as fuel injection, yea, that'd be great. A little cost-prohibitive, though. I've installed and tuned EFI systems in racecars, so I know how to squeeze power and economy out of various systems. I'm not experienced at all with carburation, but my bro in law is, so I'll get with him about any improvements I can make.
     
  20. AVengeance

    AVengeance Active Member

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    That's where I should have stopped. I guess you knew better than to try to explain it to him.
    :dunno:
     
  21. GammaRadiation

    GammaRadiation Active Member

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    I'm done explaining physics to people who dont ask. :)
     
  22. AVengeance

    AVengeance Active Member

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    At least you put your money where your mouth was and took the question in that other thread to OnTopic to be discussed. I'd almost like to do that here with this misunderstanding about how generators work, but I know he'd never even visit the thread, or run away screaming when everyone out of Junior High told him what I said above.



    Anyway, back to the topic.

    Oh, with one sidenote. You've indirectly convinced me to add an aerodynamic bed shell to my electric truck. I'm making an aluminum tube frame, polycarbonate "body" (so I can still see what's behind me) shell. A triangle, when viewed from the side, sloped shape from the top of the cab to the top of the tailgate. The truck is so anti-aerodynamic, it disrupts the flight patterns of nearby migratory fowl. Okay, not that bad, but you get the idea. I know how much KWH it takes to go x miles, so if I can add this "shell" to the truck bed, and I can actually go more than 0.9% farther, I'll make a :bowdown: to CBFryman thread in OnTopic.

    And I'll try to get pics of my rear fender skirts for the Ninja tonight. They dont' look half bad, for prototypes.
    edit: rear fender skirt pics up on 1st post. They look "shiney" despite the flat black paint because I put some clear reflective over them. The flash makes them light up like that.
     
    Last edited: Jul 14, 2009
  23. GammaRadiation

    GammaRadiation Active Member

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    Speaking of aerodynamics, try drafting. With the taller gearing and other minor changes you might push towards 100mpg. In my truck (3.0 v6 5spd offroad suspension 4.10 gears 31.5" a/t tires) I got 26-27 at 65 following my dad towing the RV. It usually gets 20-22mpg at 65.
     
  24. AVengeance

    AVengeance Active Member

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    Pneumatic launching electromagnetic grappling hook. Infinite MPG!
    :big grin:
     
  25. 7960

    7960 New Member

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    mythbusters did this as a side myth and it didn't help.

    scroll down to
    Tailgate Up or Down Revisited: Mesh tailgate, hardcover, tailgate removal

    http://kwc.org/mythbusters/2006/12/episode_64_more_myths_revisite.html
     

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