Horrible Fuel Economy

I got an '09 FZ1 (roughly 30k miles) a couple of months ago and it has been getting absolutely terrible fuel economy. I get about 70 miles before I get switched to F-Trip, which is (70/3.8 = 18.4 MPG). On deceleration, the bike pops a ton, and I think this may be more than normal, maybe like 10-20 times on one deceleration. The bike has some modifications like -1 front sprocket and a 93 octane tune (vcyclenut) but I am always trying to ride under 5500 rpm with the occasional twist to have fun. I also have a problem with the bike running hot (it idles a little high around 1.6k even when warm), where the temperature will climb relatively high even in the winter, so I am worried about what will happen in the Texas summers. I have already changed the air filter and plan on replacing spark plugs but I'm not sure what else I can do but maybe a dyno tune.
 
It sounds like you may have a vacuum leak. Would explain running hot and possibly explain the popping. Try spraying quick start aerosol around the top of the motor and listen for an brief increase in your idol. GUI keeps easy and cheap test. Possibly an glitch in your ECU mapping.
 
It shouldn’t but who knows. Try the quick start and try to direct the spray around the base of the injectors. It might be time to pull the spark plugs for a visual inspection. They will tell you if your fuel air mixture is correct. The fact that you must use 93 octane is a little scary. That’s a bit aggressive and a overkill and costly at gas pump. Maybe a remapping is in order. I used Ivan for my 06. Extremely satisfied with the outcome and I still use regular gas. Remapping is a little expensive so let’s make sure that is the fix.
 
Hi,
Thanks for y’all’s feedback!

I used a tiny propane tank I had lying around, and sprayed the propane in the area behind the radiator above the engine… and didn’t get a reaction at all .
When I first got the bike, I used regular gas because I didn’t know it was tuned for 93 and the bike overheated a couple times… could it just be the plugs are just very dirty/damaged from that?
 
Replacing the plugs sure wouldn’t hurt. Running hot could of glazed the plugs. Curious what the old plugs look like when you remove them.
NGK CR9EK pen plug.
Although your mapping is set for higher octane you might need a different plug. Contact VCYCLENUT maybe they can recommend a plug. I forgot to ask are you running a stock exhaust system?
 
Replacing the plugs sure wouldn’t hurt. Running hot could of glazed the plugs. Curious what the old plugs look like when you remove them.
NGK CR9EK pen plug.
Although your mapping is set for higher octane you might need a different plug. Contact VCYCLENUT maybe they can recommend a plug. I forgot to ask are you running a stock exhaust system?
The exhaust system is all aftermarket from the headers onwards... didn't even think to ask if the plugs were different from stock after the tune but I'll probably do those very soon. I'm thinking maybe the ecu was flashed, the exhaust and sprocket change was done, so potentially what would be a normal lean condition from the mods is made far worse but I'll have to see.
Gosh I just want to ride this thing without worrying I'm going to destroy it.
 
It definitely sounds like you have a vacuum leak. That would explain the high idle .As for running hot. You might want to do a coolant flush. Making sure you have good clean coolant in the system. The motor running hot makes me wonder if the thermostat is faulty. Partially stuck or not opening fully to let coolant through. Maybe the water pump itself.? Your going to have the work the problem. Best of luck.
 
Well, just wanted to thank y’all again for the suggestions. Not sure if I’ll ever figure this out as I got cut off and got into an accident. Not sure if it will get totaled but honestly I may purchase another one.
 

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Glad that you are ok anyway. It's tough to get the bike hurt, though. From what I see in the pics is that the engine and frame appear to be ok. Not sure about the tail section. New Fairing, radiator, radiator shroud, mirror maybe for the most part? That shouldn't be a total, but I don't know the full extents. I wish you all the luck!

As for the possibility of an air leak... maybe the throttle body boots aren't seated right? The combination of the overheating an low fuel mileage makes me wonder if it isn't two issues and not just one.. Wish I could help more!
 
I got an '09 FZ1 (roughly 30k miles) a couple of months ago and it has been getting absolutely terrible fuel economy. I get about 70 miles before I get switched to F-Trip, which is (70/3.8 = 18.4 MPG). On deceleration, the bike pops a ton, and I think this may be more than normal, maybe like 10-20 times on one deceleration. The bike has some modifications like -1 front sprocket and a 93 octane tune (vcyclenut) but I am always trying to ride under 5500 rpm with the occasional twist to have fun. I also have a problem with the bike running hot (it idles a little high around 1.6k even when warm), where the temperature will climb relatively high even in the winter, so I am worried about what will happen in the Texas summers. I have already changed the air filter and plan on replacing spark plugs but I'm not sure what else I can do but maybe a dyno tune.
You have to include ALL MODIFICATIONS BEFORE the flash. He gives you a questionaire. I would call VCYCLENUT.
 
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