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Discussion Starter #1
Hey everyone, I have a 2004 650 classic, and when i bought it the guy gave be a box of parts, nice i know, with what appears to be the air induction system. I am only getting about 120 miles to a full tank and was wondering if this part being removed has anything to do with the bad gas mileage? If so is it worth putting it back on? Also a side question, just how hard is it to strip these bikes down to paint them? Any tips and advice would be greatly appreciated.
 

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I'd say with or without the AIS in place, will have little to no affect on your gas milage. The function of the AIS is to allow some air to enter the exhaust port to complete combustion of unburnt fuel leaving the cylinder...a cleaner emisson do-dad. First step is check your plugs and see if it's running too rich, all black and a lot of soot would indicate it's running too rich. I assume the PO has the AIS ports blocked off?
 

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Yes the ports are all blocked off. I will check the plugs and see if they are black. Can you explain what is happening when it is running rich?
 

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Rich means the air and fuel mixture ratio is wrong and getting more gas than can be fully combusted and some fuel is wasted. Incomplete combustion leaves a lot of carbon deposit behind (black soot)
 

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Air box?

Zack,

Not sure about "Air induction system." If you are talking of the stock air box and filter it might mean the owner did some work like, Air flow, rejeting, and maybe exhaust. If so the idea is more air and more gas. It could be the reason mileage is down if that is the case.

Dave
 

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Discussion Starter #7
The plugs should be good as i just had a mechanic do a full service and had new plugs put in about 2 months ago, and i think it is the 4.3gal tank. Also the plugs are spotless, not black stuff on the plugs or in the pipes. It has V&H slip ons and the carb needs to be re-jetted for the pipes, but they have scratches on the backside and bottom of them so i may replace the pipes at some point. Everything else is stock as far as i know or can tell, but i have only had it for about 3 months so my knowledge is still very little.
 

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My 650 get right at 47mpg. It is stock w/30.000+. You must be running rich to get that low mileage. How is it when you go through the gears? does it have power? Is it popping at a idle? By full tank do you mean to REV. 120 miles to rev is about 37mpg you are right that's not so good .
 

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Discussion Starter #9
It seems to be good going through the gears, and if i am running rich what would be the solution to fix it? There is no popping at idle, and to rev is what i mean. Oh one other question, on the reserve tab, what is the proper position? is it with the longer portion of the tab pointing up or down?
 

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On the fuel tab the long side is the pointer. As for rich or not at this point we need to verify your mileage. On my 1100 I use the seam on the lower filler neck (inside tank) to ensure that I fill to the same level each time. This way I know how much fuel I put in more accurately. Then I always use my trip function of the odometer, reset each time I fill tank. I get right at 41 mpg every time +/- a decimal point. Run a couple tanks thru your bike adhering to this method and get back with numbers.

Sorry if this seems the long way, but I'm not there to see/run/ride your bike so I need as much accurate info as possible. So you don't go down a wrong path and/or spend money you don't need to
 
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