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I have a 2012 rebel with 15,000 miles on it. I am only getting around 40 mpg. Can anyone tell me why? I'm having to refuel after 120 miles and that's with using my reserve
 

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Welcome to the forum. How long have you had the bike, and is the poor fuel economy something new, or has it always been that way? There could be several things causing the problem; bad spark plugs, valves out of spec, a dirty carb, or possibly something else. Dirty carbs are the most frequently seen cause of poor engine performance.
 

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Ive had it about 6 months. It's been a problem since I got it. I changed the spark plugs and cleaned the carb when I got it. I was thinking there might be blockage in the fuel line.
 

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Ive had it about 6 months. It's been a problem since I got it. I changed the spark plugs and cleaned the carb when I got it. I was thinking there might be blockage in the fuel line.
Tell us more about how the bike performs. Are you able to cruise at highway speeds, or is it low on power, too?

In addition to what flightcontrol said, I would add checking the air filter to the list. Also, tire pressure, and chain condition.

But the valve adjustment that flightcontrol mentioned would be my best guess.

.
 

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Have you looked in the tank to see if there is any rust? Installing an inline fuel filter is a good way to ensure any contaminants in the tank don't reach the carb. Fuel line is cheap, and you could replace it when installing a fuel filter if you think it may be a problem. I like the clear filters so you can see anything the filter traps. You can check fuel flow by turning the petcock to the off position, disconnecting the fuel line at the carb and placing the end into a clean, clear container and turning the petcock to on. If there are visible contaminants in the container or it is rusty orange in color, the carb will definitely need to be thoroughly cleaned.

Here are some links for installing a filter and removing rust from the tank. https://www.hondarebelforum.com/f39/tank-cleaning-7168.html

https://www.hondarebelforum.com/f39/how-to-install-a-fuel-filter-13278.html

How did you clean the carb? Soaking in carb cleaner followed by rinsing and blowing out every orifice with high pressure compressed air, or using carb spray? Spray isn't as effective as soaking.

Is the bike stock?
 

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It has peak power. I can cruise at 65-70 mph until the tank is dry. I put new tires on it a month ago and check the pressure Everytime I ride (everyday). I have already checked the chain as well. I will try adjusting the valve and see if that helps. Thankyou for your help.
 

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It is completely stock. I have not checked the tank but I but I have been adding tank and engine cleaner everytime the tank is empty.
 

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I took the carb out and took it apart and sprayed it out w/ high pressure air.
If there is varnish or other deposits in the carb, air alone won't remove them.

Is there some free play in the front and rear brake levers?
 

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It is completely stock. I have not checked the tank but I but I have been adding tank and engine cleaner everytime the tank is empty.



The tank and engine cleaners would probably affect mileage.


Try a tank of premium gas with no additives and check the mileage then.
 

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Completely stock. Hmmmmm. This is a conundrum. How certain are you that it completely stock? I'm assuming it has the stock air box and exhaust on it. If so, I would imagine the carburetor has not been rejetted.

Your speeds sound about right for stock. My bike I ran for about as complete a tank as can be done, with the throttle pegged, running right at 72 mph, and averaged about 56 mpg.

So if you're running WOT a lot, and starting and stopping frequently, running WOT up through the gears, 50 mpg is probably reasonable. Because my 56 mpg was NO STARTING AND STOPPING. It was WAO the whole time.

The only other thing I could think of, if your bike is totally stock is, maybe you have a brake slightly dragging?

My guess is that if you ran a tank as conservative as you can, and held it to 45 - 50 mph, you mpg would soar. 45-50 mph at a steady cruise in 5th gear, the AFR is as lean as it's gonna get, and covering lots of ground.


7milesout
 

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Completely stock. Hmmmmm. This is a conundrum. How certain are you that it completely stock? I'm assuming it has the stock air box and exhaust on it. If so, I would imagine the carburetor has not been rejetted.

Your speeds sound about right for stock. My bike I ran for about as complete a tank as can be done, with the throttle pegged, running right at 72 mph, and averaged about 56 mpg.

So if you're running WOT a lot, and starting and stopping frequently, running WOT up through the gears, 50 mpg is probably reasonable. Because my 56 mpg was NO STARTING AND STOPPING. It was WAO the whole time.

The only other thing I could think of, if your bike is totally stock is, maybe you have a brake slightly dragging?

My guess is that if you ran a tank as conservative as you can, and held it to 45 - 50 mph, you mpg would soar. 45-50 mph at a steady cruise in 5th gear, the AFR is as lean as it's gonna get, and covering lots of ground.


7milesout
Hahah that's a good one, i've yet to see a used bike that is "stock" (ie set up as it was when it rolled out the factory) and to be honest I don't think they exist, only the bikes with 1 owner and maybe a year or two of fair weather riding are like that
 

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Hahah that's a good one, i've yet to see a used bike that is "stock" (ie set up as it was when it rolled out the factory) and to be honest I don't think they exist, only the bikes with 1 owner and maybe a year or two of fair weather riding are like that
You're probably right. Mine was 3 years old, 44 miles, and I don't know how many times dropped … but at least twice.
 

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I was thinking some more about the 40 mpg, and yet having full power in all gears.

Could it be possible that the choke/enricher cable is out of adjustment, and is staying partially open even when choke is cancelled? Would this dump extra/more fuel into the carb than was needed, and affect fuel economy?

I admit my understanding of how these carbs work is limited, so maybe someone more familiar could comment?
 

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VAReb - That is an excellent thought. Sounds very plausible. I can tell you our choke / enricher is very effective. And that this bike runs very good, even very rich. So yes, that could be the issue.
 

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You're probably right. Mine was 3 years old, 44 miles, and I don't know how many times dropped … but at least twice.
Hah, it's always like that when you think you've found the perfect used bike but it turns out to be neglected and disused, as was the case with mine. Mine's done barely 2000 miles in over a decade.. The OP is talking about 15,000+ miles stock, I don't think he knows his bike that well yet, no bike is stock at that mileage.

VAReb - That is an excellent thought. Sounds very plausible. I can tell you our choke / enricher is very effective. And that this bike runs very good, even very rich. So yes, that could be the issue.
I'd imagine the spark plug would give it away, it would be very fouled if this was the case and I don't think the OP has checked that thoroughly
 
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