1993 gsx600f Katana dropping cylenders

[Eric600]

My Kat sounds like it is dropping cylenders. When I crank it up cold it runs perfect and screams when I get on the throttle. But when it warms up it sputters in and out of cylenders and eventually it just drops two...or this is what it sounds like. Im guessing this because there is a big power loss and it sounds more like a v-twin. Also when it does this it will not idle.

I have two theories. One is the fact that it has K&N short air filters and a Yoshimura exhaust. I read that you have to work on the carbs when there is that much extra airflow coming through. The other is that the ethanol fuel I put in it is gelling up inside the tank. But where in the hell can you get gas that isn't 10% ethanol?

Please let me know which of these is right or if I'm way off. I plan on taking it to a shop so if anyone knows about how much this would cost to get fixed that would be great.

Thanks

[Kreylyn]

My Kat sounds like it is dropping cylenders. When I crank it up cold it runs perfect and screams when I get on the throttle. But when it warms up it sputters in and out of cylenders and eventually it just drops two...or this is what it sounds like. Im guessing this because there is a big power loss and it sounds more like a v-twin. Also when it does this it will not idle.

I have two theories. One is the fact that it has K&N short air filters and a Yoshimura exhaust. I read that you have to work on the carbs when there is that much extra airflow coming through. The other is that the ethanol fuel I put in it is gelling up inside the tank. But where in the hell can you get gas that isn't 10% ethanol?

Please let me know which of these is right or if I'm way off. I plan on taking it to a shop so if anyone knows about how much this would cost to get fixed that would be great.

Thanks

I don't think it's your fuel since it runs fine when cold.

I do think if your using pod filters, you probably have an issue. Possibly some work was already done to it to counter the pods... and they made it too rich, so now when it's warm it's wanting to foul out plugs.

Could also be a heat affected issue with the spark somewhere... a coil issue or something along those lines, a bit of testing can help narrow it down.

First, make it show the problem... then check the temp on each down tube for the exhaust. Note the temps.

A colder tube than the others is a sign that is the specific cylinder your having a problem with. That info will point where to go next (electrical or further carb tuning).

Personally... I would ditch the pods and get a OEM airbox and filter. Even if that isn't the primary problem, it's contributing to a problem and making the bike run worse than it can/should.

Krey

[chilln191]

....

[Kreylyn]

I see a lot of people with problems with the K&N filter. I also have a V&H exhaust. I have no issues. Did i just get lucky when these were installed? don't mean to jump on your thread. sorry...

Take the bike to a shop with a dyno, post your chart.

1. It will show you really don't have a problem and we'll all bow to the uberness that is your bike, as it's really that rare...

or

2. It will show you that you really do have issues, and your butt dyno just isn't sensitive enough...

Krey

[arsenic]

I'm gonna go out on a limb and say it's #2.

[chilln191]

........

[arsenic]

How is a 750 closer to an 1100? The biggest it can possibly be is 811.816400490177 cc's, trust me, I've done that. And unless you have aftermarket cam shafts. Displacement matters not. The smallest stock 1100 is a 1052. The Katana 1100 is 1127 As someone that HAS an 1127, I find that rather offensive.

[cintidude04]

As someone that HAS an 1127, I find that rather offensive.

[Kreylyn]

maybe cuz my engine isn't stock?

ummm....

I just can't find an appropriate response to this...

Krey

[Patch's]

While I'm not a fan of the K&N filter not because it may allow more air but because it will allow more contaminants past it then reverse it's character and choke it off oddly just after it hit it's high filtering capacity which makes it fine for track but not for street.
If you are loosing 2 cylinders than check after it stalls to see if the plugs are wet or dry and if wet are they paired to the coils, coils will behave poorly when hot if there defective.
I would also take a compression test if you can so as you can point to your filters later on when the premature ring ware appears from the chit getting past the K&N.
Chilln I get your bragging right's but Arsenic spoke "volumes" in just 2 lines! if you just look past the the punt, take the schooling when ever or how ever pitched if it interests you, key words displacement and cam, look them up you'll see why one with out the other is a bit of a fudge
You sure can teach a class Arsenic, where do you store all those numbers man?

[arsenic]

You sure can teach a class Arsenic, where do you store all those numbers man?

This is ALL I do. I'm damn good at it. When you only know one thing, it's not hard to remember all this stuff.

[chilln191]

yep. guess i don't know what i have or had done. arsenic is "all knowing". if he can't do something then it can't be done. if putting money into something that might be better than someone elses is offensive, then i guess i am offensive. i shall delete my post and and let the "all knowing" mighty one, have his glory.

[mammut89]