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[guitardav]

Help wanted.
My 2006 Katana 750 has a problem that is wierd to say the least. After riding it hard (high RPM) it will suddenly and without warning just dies. It's just like the main kill switch has been turned off or like if the kick stand has been put down while in gear. The lights and all electronics work just fine except the starter won't crank. I then have found that if I take the seat off and take something like a knife and tap on the small black relay box beside the fuse box it usually starts right back up. I have replaced this box with a brand new one and the problem still persists as before with the old one. I have cleaned the electrical connections and inspected them around the fuse box and the relay and also looked for a loose connection to no avail. I am stumped. Has anyone else ever had a similar problem and if so what did it take to fix it? I am afraid to take the bike on and long rides or even get out on and interstate for fear of being killed when it dies in the passing lane.

[samman128]

i'm having a similar problem with my 00 600, minus the pulling the seat off it will normally start back up shortly after. i am assuming my issue has something to do with lack of fuel even though i have plenty in the tank, does anyone have more info on this?

[SerialBanger]

Just my 2 cents but a bad ground maybe? What about a bad kickstand kill switch? Try and bypass the kill switch and ride like you do and see if it still happens... Hopefully someone wiser will chime in soon... My bike died on the highway at high RPM because my float height was set wrong and i was running the floats dry... But it stumbled in that instance not like yours...

[Negster]

I had a similar situation yesterday. I was out riding on the interstate for about an hour and got off to take some country roads back home. While in the middle of absolute NOWHERE, the bike just started to lose power. The bike stayed on and it slowed with no response on the throttle. As I came to a complete stop on the two foot wide shoulder, the bike finally just turned off, but I still had instrument lights on. I sat on the side of the road admiring the beautiful cows grazing in the pasture for about 20 minutes trying to figure out who I could call to pick me up. I tried to start the bike and it fired up again. I then hit the road again for about 45 more minutes before it did it again. I again waited a short while before it started up and I finally made it into town.

The bike only shuts off on high RPM as I am cruising at 70-85 MPH. It doesn't turn off until I am at a complete stop, but as the engine loses power and the RPM's start falling, the bike has no response to the throttle. I haven't done anything unusual on the bike and this only happened one other time back in October 2010 after I changed the gasket on the crank case on the left side of the bike.

I have never had the carbs cleaned or anything like that. So could it be that something clogged up the carbs or maybe a clogged fuel line or maybe something to do with the spark plugs? I'm not much of a mechanic but I'm willing to learn.

The bike is a 2005 Kat 600 with just over 29,000 miles. Any ideas would be fantastic! Thanks everyone!

[1FSTKAT]

I have had the same problems
Do this:
Remove your gas tank, make sure that the main fuel line coming from the tank to the carbs is the right length, too long and it will kink, this wont provide a problem for a while but under heat the line expands and stops the flow of gas to the carbs. If the line seems kinked or just a bit too long take a razor knife and cut it bit by bit (don't cut too much off) until it fits without any problems.

[KAT TOY]

Just my 2 cents but a bad ground maybe? What about a bad kickstand kill switch? Try and bypass the kill switch and ride like you do and see if it still happens... Hopefully someone wiser will chime in soon... My bike died on the highway at high RPM because my float height was set wrong and i was running the floats dry... But it stumbled in that instance not like yours...

my issue with this problem was the kickstand switch. my mounting point for stand is worn plus a weak spring would cause the switch to open. i bypassed the switch and have had no problem since.

[steves]

If it's not electrical, next time you are out and it starts doing that switch the petcock to PRIME. Could be a van issue too.