I'm new here, new owner of an '01 F4i. Just got it with about 3200 miles, looks like brand new but hasn't been registered since it was brand new and has obviously hardly been ridden. I noticed when I put the first tank of new gas in it (93 octane) it started running noticably smoother and quieter, and after I had ran a couple of tanks through it, it seems to have settled in to how it runs now. I rode an SV 650 for a long time before this bike so I'm still getting accustomed to the power and characteristics of the I-4, but it seems like at highway speeds it sort of pulses constantly when riding at a steady pace. It doesn't feel quite right but I don't have anything to compare it to so I'm not sure.

And the 22 miles per gallon is way bad from what I've read here. I work as a courier on this bike so I certainly ride fast, about half city streets half highway.

Does anyone have ideas or suggestions on the gas mileage problem and the surging issue? Could the injectors or fuel lines be gummed up? Help! Thanks

 

When you say highway speeds, do you mean you'll be cruising at say 40mph at 4k rpms(give or take a few hundred) and the engine won't have that inline-4 purr?

 

These bikes are honestly rated to use regular, 87 octane. I always use midgrade just because (89 octane). 93, with a very high flashpoint, wouldn't necessarily cause any mechanical problems, I would just recommend using lower octane, even switch down to regular driving it relatively easy, and see how it performs.. Just give it a shot, see what it does..

 

If it had been sitting for a long time (years), like you said, you are probably experiencing gumming up of the gasoline. Another thing, take a look inside the airbox and make sure there are no blockages in the air intake like, a blocked air filter of bird nest...etc.... You will want to in spect the fuel lines to check to see if fuel is flowing through them, and if possible take a look at the fuel filter and pump. If you have run a couple tanks you are definitely getting fuel to the injectors but you might have something holding you back from unrestricted flow.

Not sure if anyone has used fuel injector cleaner on a F4i but that comes to mind as well.

Also, does this bike have stock gearing and sprockets? What RPM are you at going 65-70mph?

Are you riding in top gear on the highway and are you reving the rpms out frequently?

Keep us posted...

 

I will be putting in 87 next fill up, but this still couldn't cause 22 mpg could it?

When I say highway speeds I mean 75-85. And it has the sweet purr I expect, it's just really hard to keep a steady speed. The speedo basically indicates a nearly constant 2 mph fluctuation, for example going from 79 to 77 back to 79 about once per second.

 

I used Fuel Injector Cleaner (STP) on mine. DO NOT do it. Sputtered and hesitated the whole time, I was a happy camper when i finally went through the rest of that tank.

 

i say...stop riding highways in second gear and you'll get better mileage! hahaha...j/k...

how are you measuring how much gas you're putting in? all the way to the filler neck...all the way mang...

 

I just got 50mpg for 2 tanks in a row, so 22 is way off. Octane won't really affect that number that much, 93 is a waste of money, but it won't hurt anything, emissions may rise, but not by much. Check all the basic bits, airbox, plugs, brakes hanging up, fuel filter, clogged injectors...then after that various sensors and whatnot. Anything not stock on it, PCIII? Pipe?

If it idles OK then just live with it while you check things, with all the detergent in todays gas, you may find the situation improving.

good luck.

 

Hey Matt: Way to steal my banner. Go get your own idea! j/k

 

I get about 160miles on mine before res. grid comes on. Is it possible your float is stickin or has it been empty when you filled up. If it has been empty then you are runnin waaaaaaay rich and something needs cleaned out. maybe you loosin gas out of the breather tube while riding. Just some other ideas.