[scottynoface]

I have the manual that was on Scribd from a thread on here because i did not get one with the bike. if this matters and can be accessed, page 29 in the manaul under fuel/oil recommendation it says: Use unleaded gasoline with an octane rating of 91 or higher research method. This is qouted verbatum.

Research method = RON

in the next paragraph it says for Canada: Your vehicle requires unleaded gasloine whenever possible,with a minimum pump octane rating of 87. Verbatum. So i don't know. As i said, i guess i'll split the difference and run 89. I cannot see where running 91 or 93 would "hurt" the engine when a higher octane rating would result in a more even and thorough combustion cycle where as a lower rating of 87 would not combustion as thoroughly. I could be wrong.

Yes, you're wrong. The katana engine does not have a high enough compression ratio or enough ignition advance from the factory to require anything higher than 87 octane. You're getting a dirty burn because the bike isnt designed for 93 octane.

Higher octane does not equal more power or a cleaner burn. Higher octane is used in high performance engines to prevent pre ignition, your bike cannot take advantage of that.

Now, as to your original issue. Have you checked for fire on all four plugs? Plug wires cracked or brittle?

[steves]

I'm not sure what thread on Scrib'd you are referring to... but... I wouldn' trust any site that's scraping content out of context from KR.

[hukeedo]

If i'm getting a "dirty" burn from high octane, that could be the problem then and I killed the plugs. Well, i'll just run the 87 from now on and just save my money anyways, and if you guys say its ok, then i'm good with it. I posted another thread on spark plugs because i want to start with the easy and inexpensive stuff first but without ordering the CR9EK as the manual states it takes, and for 10 bucks a plug, I can get standard single prong CR9E for 3 bucks but didnt know if i can run those or not. Hell, it could be the original plugs in there for all i know and could be the source. I checked the wires and all is well in that area. I did not check the spark from the coils but after i put new plugs in and see how it runs, i will go from there. The manual on scribd is directly copied from the original manual that someone had in PDF form. So i thought is was OEM. But I am leaning to plugs because it ran perfect all the way up and when i started it at my destination, it idled perfect and didnt have the miss, ran perfect home and i noticed the miss at idle when i pulled in the driveway, so something small happened in a very short time.

[hukeedo]

update

So i got single electrode CR9E plugs and put them in. Fired it up and it still ran with the miss and it was really noticeable. Pulled the wires and wired the clutch lever in and used the old plugs to check for spark and got good spark in all wires.
Put the wires back on and fired it up, still the same. Decided to turn the reserve on because the tank seemed light with gas, started it up and ran it. Shut it down and started it up again and what do you know! Ran good again. I either had vapor lock, low fuel or something going on with the fuel. My gauge was reading above E but i have realized that maybe the sending unit may be off and i assumed there was gas in it when there was actually not probably enough in there to feed all 4 carbs, thus running it starved. Thats the only thing i can think of. It's going to be too cold here to ride for a while, but next day above 50 i will test it and run it for some miles (after i fill the tank) and see how it goes. If nothing else, it has a fresh set of plugs!
Thanks for all the input. BTW, i will run 87 octane from now on as well.

[voyagerr2]

i recently had a pilot jet issue on 1 cyl. ran ok with more throttle. i ran a mixture of stabil marine concentrate and marvel mystery oil to clean jet. it worked! i was pleasantly surprised. try a fuel cleaner made for ethanol. it won't hurt if you follow directions. spark plugs do cause issues sometimes, so your fix should be inexpensive.

I'm going through the same issue with my kat. I narrowed it down to a jet issue. When I get to 5k the engine totally bogs out. Today I added white gas and the same type of fuel stabilizer and am now thinking about your Marvel, Mystery Oil"MMO" solution. How much MMO do you add to a full tank? Next it's a carb rip down if these things don't work. FYI my Kat is a 2000, 750cc with 12k on it.

[scottynoface]

So i got single electrode CR9E plugs and put them in. Fired it up and it still ran with the miss and it was really noticeable. Pulled the wires and wired the clutch lever in and used the old plugs to check for spark and got good spark in all wires.
Put the wires back on and fired it up, still the same. Decided to turn the reserve on because the tank seemed light with gas, started it up and ran it. Shut it down and started it up again and what do you know! Ran good again. I either had vapor lock, low fuel or something going on with the fuel. My gauge was reading above E but i have realized that maybe the sending unit may be off and i assumed there was gas in it when there was actually not probably enough in there to feed all 4 carbs, thus running it starved. Thats the only thing i can think of. It's going to be too cold here to ride for a while, but next day above 50 i will test it and run it for some miles (after i fill the tank) and see how it goes. If nothing else, it has a fresh set of plugs!
Thanks for all the input. BTW, i will run 87 octane from now on as well.

Yeah, the gas gauge is a rough estimate at best.

[hukeedo]

I had lengthy fuel issue with the Kat. After new float needles and weeks of head scratching it ended up being a bad petcock. These bikes are troublesome in the carb/fuel delivery dept I have come to find out the hard way and mine only had 13k on her when I got it a few months ago. But when it's running the way it should, I really love this bike. Hope you get urs sorted out. And yes I have definitely come to see that the fuel gauge is more of a concept on these bikes and not a tried and true means of determining how much fuel is in the tank. I have noticed worse fuel economy since putting on the yoshi rs-3 exhaust system, or maybe I love the sound and the throttle response so much I'm on it more!

[voyagerr2]

I had lengthy fuel issue with the Kat. After new float needles and weeks of head scratching it ended up being a bad petcock. These bikes are troublesome in the carb/fuel delivery dept I have come to find out the hard way and mine only had 13k on her when I got it a few months ago. But when it's running the way it should, I really love this bike. Hope you get urs sorted out. And yes I have definitely come to see that the fuel gauge is more of a concept on these bikes and not a tried and true means of determining how much fuel is in the tank. I have noticed worse fuel economy since putting on the yoshi rs-3 exhaust system, or maybe I love the sound and the throttle response so much I'm on it more!

Good call, I didn't even think to check that. I noticed a big lag on a switch over to reserve when I ran the tank down. But still I I'm going for and acid wash and needle replacement on the carbs. I'm gonna change the peacock out too.

[voyagerr2]

Monday
After completely draining my tank and lines I added a fresh tank of white gas (0% Ethanol), concentrated carburetor cleaner and let it idle for a while. I took it for a ride and no change, in fact it was worse. So I parked it and let it sit for a couple of days

Tuesday
Didn't even look at the bike.

Wednesday
Pretended the bike was under my cover in perfect working condition.

Thursaday
My day off and I felt bad for my Kat. I gave her a deep scrubbing and a buff job that made it look like wet glass. I also removed the center stand for cleaning and new powder coat.

Friday
It's off to work at 1730. She started up quick and held idle quicker then usual. Ok so lets take it easy on her and back road it to work so I will not have to worry about that 5k rpm bogging.
Wait! This feels strangly smoother then before. Change of plans and I turn onto the highway. 4500 rpm, smooth, 5k, I should be getting bogging anytime now. 6500k, what!!!! It's smooth holy %#?%! Opened her up clean to 120mph and sustained it for a 1/4 mile before backing off.

But I'm still pulling the carbs and giving them and acid based cleaning!