Terrible Gas Mileage+ exhaust melted wires

Hey guys just got this bike a couple of weeks ago and now I discovered a couple problems. Bike has 3600 miles on it. AIS and Air flapper mods. Powercore 4 exhaust


1. I only get around 35mpg (edit 50mpg lol). Fuel light comes on after only 75 miles
2. Exhaust Powercore 4 attached to stock header looks like it melted some wires. It has the adapter for the stock header in it but nothing holding it in.

Could these problems be related? Also what exactly is that green plug for?


Thanks in advance for all the help! Attached are some pics of the damage. You can see that the wires look exposed in some areas.

That's the temp sensor for EFI. It doesn't tell the fan to turn on, it tells the computer if your engine is cold or warm. Could be the source of the problem. If the computer thinks the engine is cold it adds more fuel.

Check your math.

1.5 gallons of gas until fuel light comes on with a stock tank.

If you get 75 miles until light comes on that's 50 mpg.

Here's mine after almost 10,000 miles



Something is surely not right if you're getting that much heat in that location.

I'd check the radiator coolant to see if it's proportioned correctly for your climate.
I'd check to see if the cooling fan is working.

Do you have a fuel programmer? You did not list one, but usually if there's a pipe and airbox mods people recommend a fuel programmer.

I doubt being slightly lean would cause that kind of heat.

Are you sure that "melting" is not something that happened thanks to the previous owner? Can you contact the previous owner and ask what might have happened?

I don't think the exhaust/header has much to do with it unless they did not use the coupling spacer provided and there's a shit-load of exhaust gas escaping out at that location. You'd be able to feel it and hear it I'd think if that was the issue.

I have a stock header and an FmF Q4 pipe. I did not use any sealant at the connection between pipe and header, just the coupling spacer FmF provided.
You can see the condition of my wires.

I checked radiator is full and oil is near full as well.
I'm in Hawaii so the weather should be a non issue.
I don't have a fuel programmer, but the guy I bought it from said it as a ok because he changed the CO settings? It is currently set to 4.

The adapter for the pipe is in there already and I don't feel any exhaust leaks.

Also the fan comes on after sitting in traffic for a 10 min, so I think its working as it should.

I can't think of anything else to check

I'd get some new shrink tube and cover those wires.

Then I'd ride bike to see if it's something that's currently happening.

Do you know for a fact it's not something that happened long before you bought bike?

motokid wrote:

I'd get some new shrink tube and cover those wires.

Agree. However, I would check the wires for a short first. If they're touching, you'll have to separate them individually and re-insulate them.

BuilderBob wrote:

motokid wrote:

I'd get some new shrink tube and cover those wires.

Agree. However, I would check the wires for a short first. If they're touching, you'll have to separate them individually and re-insulate them.

Did you guys get anywhere here?

That's the mileage I get, but it seems pretty close to normal. It gets a little better if I slack off to 65-70 mph.

75 miles to the fuel light is about average.

After reading all the post I think that exhaust got too darn hot. Reading through this forum for a year and I dont think I would run an after market exhaust without a programmer, especially with intake opened as well. Is your leg getting warm?

Nope. I am completely stock, and wasn't involved in this 10 month old thread before now.

The OP described 50 MPG as "terrible", and it was close to what I got.