Alright guys, I've read through the forum and done searches on this. I haven't found anything that really sounds like the cause of my problem here. So here's my problem-

Fired the bike up and started great, like always. Let it warm up and took it for a spin down the road. I'd say I went about a half mile down the road and then the bike just started running like crap. If I gave it more throttle it'd just bog itself down to an almost stall. I could only ride at about 3k RPM or it would do the bog down. I turned around and drove home.

I then let it sit for a minute at idle which was very rough. Then noticed the exhaust tone was hitting differently, it sounded like my buddies GS500. So I thought it's missing on a cylinder or 2 since it sounds like a twin cylinder. I sprayed some carb cleaner all 4 header pipes to see if the cylinders were firing- 2 of the 4 header pipes burned the spray off right away and the other 2 burned away but not as fast. So this led me to believe that I have 2 cylinders down. I then got upset at this and revved it up to 10k in hopes something would just clear up and 1 flame about a foot shot out of my pipe.

Last night, I replaced all 4 plugs-which i will say is a BITCH. 2 of the plugs had some oily residue on them, not thick or dripping but like a molasses feel to it. While I had the tank and filter box off I started her up again and sprayed carb cleaner directly into each carb. Let her run out of gas. Then put it all back together.

Started it back up. Ran great again. Sounded like it should again- on all 4 cylinders. I let it warm up to normal temp and took for another spin down the road. Felt great again. I was able to rev it up to anything and had no loss in power. Got about as far as I did last time (half mile) and it started running like crap all over again. If I put choke on it would idle fine, but take choke off, it wanted to stall. What get's me is that I let it warm up for 15minutes in my garage prior and I was able to rev just fine, now just 2minutes on the road if I open the throttle the engine just bogs down and stalls.

So here's my 3 conclusions as to what might be happening- Readers will have a laugh here....

1. I recently had my bike repainted, the gas tank had a dent on it so the guy fixed it for me, but had to work on the dent from both the inside and outside of the tank. When he painted it, the filler hole was taped off as well as all openings under the tank. I drained the tank as best as I could prior to painting but, like an idiot, never flushed it out after I got it back.... So could there be something cloggin the fuel lines so at higher rpm's the engines not getting a supply of gas which would lead to the bogging down and rough idle? Change the filter rinse the tank and put fresh gas in it?

2. When I drained my gas prior to painting I put it in a gas can and then refilled it from the same container after paint. The problem comes into the fact my roomate never told me until after my 1st ride when my bike bogged down, was that the container had CAM2 RACE GAS in it. So I was probably running a mix of 60% cam 2 and 40% 93octane gas. So did the cam 2 mess with the timing and engine specs so it runs crappy and now all I have to do is completely drain the tank and put pure 93 pump gas in and the problem will magically dissappear?

3. Or did the cam 2 gas severely damage something like my piston rings?

4. OR IS THERE SOMETHING ELSE I'M NOT ADDING INTO THE EQUATION?


WHAT DO YOU GUYS THINK........ANY FEEDBACK WOULD BE MUCH APPRECIATED......

 

well you dont need 93 oct fuel unless you've done extensive mods. The bike was designed for 91 or 93 RON which correlates to 87 octane. It sounds like your running out of fuel. Make sure the fuel line is hooked up correctly. I had to replace mine a couple years back and didnt order the preformed one. when I set the tank on it would bend the line and cut off the fuel. It would run out and then start bogging. If I backed off of it it would fill the bowls back up and then run out till it was starving again. I would say its either bent fuel line or clogged from the paint. Good luck.

 

Thanks man, I'm getting a new fuel filter today and I'm gonna try all the "easy fixes" before I tear into the engine.

 

I don't forsee any reason to tear into the engine. If the easy stuff doesnt work you may have to pull the carbs and check the bowls for debris.

 

Ok, so for those that run into the same problem......Here's what I did to correct my issue:

- Also checked the battery, I had read in some previous posts that people with dying batteries were running into almost the same issues i was. SO checked it and found that while the bike was "off" and key was "off", it read 11.5v, when the key was turned to "on" but bike was not running the battery dropped to 8.7v and obviously wouldn't start. So bought a new one from autozone for $59.

- Just to be sure it wasn't a fuel issue, I completely drained my gas tank. I removed the gas switch valve, sorry can't think of the correct term, so that there was just a big hole on the bottom of my tank to let the gas run out. Got as much as I could out.

- I drained my Carb bowls, then tightened everything back up, put the fuel switch back on my tank, put about 2 gallons of good fresh gas in. Added some seafoam to the gas.

I started her up, ran rough for about 4 minutes or so, and took her down the road. At first she wouldn't rev past 4k without wanting to die, after another minute down the road, got it up to 6k no problem, then about 10min into the ride she was able to rev up through the band and had no more issues.

So moral of the story..........either I had a fuel getting to the engine issue or my system didn't produce enough to power the ignition system. Either way, runs great again and learned a little.......

 

Nice man. My two cents are probably not needed seeing as how you're running well now, but if it were me, being that there could have been a fuel line blockage, I'd pull the carbs, tear them down (not off the rack, just the float bowls, diaphragms, and air funnels) and blow out all the galleries. If you had some particulate in your lines you could have small bits in you emulsion tubes among other tiny hiding places in the carb's air/fuel passageways.

It's not as scary as it sounds, you'll learn a ton about your carbs, and can determine if any seals are damaged and contributing to either a lean or rich condition. I would do this because of what you said about the center crabs fouling out. In the F4 the center carbs are tuned differently from the outside two to push more fuel through to match the increased heat.

If you do clean your carb galleries, make sure to spray from the smallest hole through to the larger hole so you don't wedge anything further. WD-40 is the best because you can see any leeks easy and it cleans very well (and it's cheap)

The best thing about doing this if you're not the original owner; you can find out who's been messing with your ****. I did my carbs recently and found 118 and 120 main jets in there.... Factory sea level setup is 132 and 135, high altitude is 130 and 132... somebody gonna get a hurt real bad.

have fun.