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Re:Miles per gallon
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TOPIC: Re:Miles per gallon
#1657
MikeS (User)
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Miles per gallon 13 Years ago  
Hi guys, I was wondering what kind of gas mileage you fellow riders were getting. I have the stage two kit. Exhaust, carb kit, K&N filter. I get 33 mpg pretty much consistantly. I used to get around 45mpg before the modifications. I think I'll rejet back to the factory. I'm not into running the bike rich and I dont think it makes anymore horsepower. I havnt pulled the plugs but I bet they'll show the bike is running rich. I cruise and dont race.
 
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#1661
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Re:Miles per gallon 13 Years ago  
If you go back to the factory jetting you need to go back to the stock air box and filter.
 
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#1662
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Re:Miles per gallon 13 Years ago  
At the worst, I get 41 mph and best about 49. I would go so far as to say that I am about average for gas mileage.

The upgrade should not have worsened your mileage but you may have over-compensated with re-jetting. What jet brand did you use: Mikuni or Dynojet? What size primary did you use? Where did you place the clip and washers on the needle? Also, did you change your float level? It may be set too high.<br><br>Post edited by: SunLaker, at: 2005/02/21 08:15
 
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#1670
DocShadow (Admin)
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Re:Miles per gallon 13 Years ago  
I have Nasties and a BAK and I get much better mileage.

IMHO most guys seem to run their bikes too rich. Rub you finger inside your exhaust and see if it's real black.

As was said, you cannot go back to stock as the bike will not run well. Post your carb settings, maybe someone can help.

Doc
 
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#1676
MikeS (User)
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Re:Miles per gallon 13 Years ago  
I dont know what jets are in the bike. Bought it this was. Why does everone say you have to rejet when you change to a less restrictive filter. I havnt seen any dyno work to back up the theory. And the exhaust pipe it black and sooty. Thanx. Mike
 
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#1677
GRAM (Visitor)

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Re:Miles per gallon 13 Years ago  
We understand your concern Mike, but the theory bihind jetting is pretty simple. Change your airflow, and the jetting requirements change.

If you want to see this in action you should check into some of the manufacturers websites. Some have been kind enought to suply Dyno run results, but the more important thing to tune into is Air/Fuel ratios.

When you go from a fairly free and or open flow system to a more restrictive one, the air flow naturally decreases. The fuel flow in this system does not decrease at the same ratio. You end up rich when you do not change jetting and reduce airflow. The inverse is true when you open up airflow. You will end up lean if you do not compensate in your jetting setup.

If you leave your aftermarket accessories on, and change your jetting back to factory settings, you will be lean. The factory settings are designed to complement the airflow of the factory accessories, which you are no longer using.

With the mileage you are getting, you are clearly rich somewhere.

There are a lot of very experienced carb tuners on this site, who know this carb very well. The very best thing you could do would be to find out and post here what your settings are. For example, the main jet installed in your carb, the number of turns out your PMS screw is, and the size of your pilot jet (if no longer stock). I am sure you will get some very good advice about what to do next.

I am betting that with that kind of mileage your main is too large. Do you know if the guy who set the carb up installed an aftermarket needle? If he did not, he may have chosen to compensate with an oversized main jet.

It would help to know who's needle (or jet kit) was used for the rejet (if an aftermarket needle was used).

We want to help, but need to know more about your bike to do so.

GRAM<br><br>Post edited by: GRAM, at: 2005/02/22 01:05
 
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#1683
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Re:Miles per gallon 13 Years ago  
Simple test (works REALLY well with stock bikes). Pull yoru air cleaner off and fire up the bike ... whack the throttle once ... when you bike dies or nearly dies just by opening the throttle, it will be realy obvious you need to make adjustments. Less restrictive air filter means the bike can gulp more air. Since jets are sized to air flow, the jets will be too small to keep enough gas flowing to keep up with the increase in air flow.
 
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#1813
Rats Daor Dan (User)
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Re:Miles per gallon 12 Years, 11 Months ago  
Any luck with your re-jetting?
I'm currently averaging 46 mpg, with a MaxAir airbox and stock pipes drilled to stage 3. Your needle setting is probably what needs adjusting. The main jet isn't likely to affect fuel economy much unless you're always giving it lots of throttle. While we may think we ride our bikes hard, it isn't likely you spend a majority of your time at 3/4 throttle or higher in normal riding.
My mileage used to be higher, but my PMS setting was too lean and I had some hesitation in early throttle so backed it out some more.
 
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#1951
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Re:Miles per gallon 12 Years, 11 Months ago  
Mike,

I have an '05 RS, I had the dealer put Cobra Loboys on, and rejet. Stock air. I started out getting 32 m.p.g., and had black, sooty pipes. I took it back, and they said that &quot;The young guy&quot; put in a 195 jet instead of the specified 175! They changed it, no charge.

I have had only one ride since then due to cold weather, but got 40 m.p.g. I think with a bit of tweaking I could get even better. Warm weather will help, too.

&quot;Odo&quot; (Joel) on the Forum, said he gets more than 50 m.p.g. sometimes, but high forties seems to be common.

What's been happening with your bike? We need an update.

Shep
 
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