Any ideas on what happened?????

[soulpatch]

I was driving up the highway the other day. I was speeding (around 110 or so). I was riding behind a car for a while then cranked it to pass them when the road cleared up. Well I cranked it up to about 110 or 115 and the bike sputtered and died on me. I drifted to the exit in nuetral and sat there for a few minutes. My oil lamp came on. I shut off the bike and waited perhaps 5 minutes.

I turned the key and she started up with a slight putter at first. Then she purred just like normal. I have not noticed anything since.

Any ideas on what happened????


Oh and she was just into the shop last month for inspection and oil change so it shouldn't have been my oil.

[babybusa]

check to see if you have oil in there and the right amount and post back.

[soulpatch]

When I got to the office I looked in the oil window. The oil was at the F line so it is full of oil.


That was my first thought too.

[Jax]

Maybe the kickstand switch got activated...check your spring and make sure it doesn't sag a bit...I've done the same and noticed that it only takes a little movement of the kickstand to set it off...changed my spring and I was back in business again...

[Mojoe]

I am betting he maybe drained the carbs. it usually takes a while at high speed, but maybe his filter is plugged just enough that the bowls could not fill fast enough. it is normal for the oil light to come on if the bike is not running.
the bowls filled back up and he was fine after.

[soulpatch]

Perhaps it was the kick stand. I can see that one happening.

Though the bike became almost sluggish and choppy before powering down. I could see the kick stand vibrating against the cut off point to where the engine would almost die then the stand move so it keep running until the stand went to far.

When I pulled over I put the stand down and waited a moment to try to restart.

[soulpatch]

I am betting he maybe drained the carbs. it usually takes a while at high speed, but maybe his filter is plugged just enough that the bowls could not fill fast enough. it is normal for the oil light to come on if the bike is not running.
the bowls filled back up and he was fine after.

Sorry I am not much of an engine guy so you have to explain this on eto me. How would this happen? Just from flooring it? Is this a commen problem? Anything I can do to stop it from happeneing in the future?

[Mojoe]

the kickstand theory could be possible, but it would either run or not run. it would be like hitting the killswitch....no sputtering. sputtering usually means fuel starvation or misfire.

[meanstrk]

The Katana has long suffered fom fuel starvation when running high speed for extended periods. Basically, the fuel flow has a hard time matching demand. You can try playing with float height and it "might" help, but the best thing you can do is ensure that the tank screen is clean, and no blockages are in the fuel delivery system. Mine use to do it protty bad until I made sure that everything flowed as well as possible.

[soulpatch]

Well yes I had been at high speed for about 15-20 miles. I slowed down shortly as I waited for an opening around a car then shot back up to speed.


The fuel supply sounds more logical after hearing you all. I will have my uncle check all the lines and screens for blockages when we put her down for winter. Only a few more weeks of riding left really.........

[skotty]

+1 on the kick stand theory.

I am guessing that if you have a weak kickstand spring or if there is a large gap (due to the metal wearing out) at the end where your kickstand is bolted to the bike, and at 110 - 115 mph, there may be just enough vibrations to have the kick stand come out and disengage the switch. A similar incident happened to me this morning;

http://www.katriders.com/forums/viewtopic.php?t=24477

[The CyberPoet]

I'm on with the fuel supply issue too...

On a bike of your bike's age/model, I'd say run the tank virtually empty (drain the rest) and then pull the petcock and check the screen on the petcock -- this is the place where it's most likely to be getting starved for fuel IMHO.

The second most likely place is at the petcock itself -- that the petcock isn't flowing quite enough. Simple way to test: when it starts to sputter, immediately reach down and switch the petcock into the PRIME setting. If the problem disappears in about 10 seconds and doesn't return for the rest of your high-speed run, then it's the petcock (or vacuum tubing to it) that's giving you the issues. Make sure you switch it back to "ON" before you shut the bike down.

Final possibility that comes to mind is that at the very top end of your throttle openings the mixture is far enough off to foul up the spark plugs temporarily. When you coasted down and restarted, they had fallen back into their optimal operating temp and burned off the fouling. This one is much harder to diagnose (dyno run with an exhaust sniffer), and even harder to rectify usually (because it's difficult to jet to fix just one end of the spectrum without changing all the rest -- if this is the issue, I'd suggest trying an Ivan's Jetkit as a solution).

Cheers,
=-= The CyberPoet

[soulpatch]

Thanks for all the help guys. If good weather this weekend I will nag my uncle to sit with me to go over the bike and the fuel supply.

Thanks again.

[Mojoe]

+1 on the kick stand theory.

I am guessing that if you have a weak kickstand spring or if there is a large gap (due to the metal wearing out) at the end where your kickstand is bolted to the bike, and at 110 - 115 mph, there may be just enough vibrations to have the kick stand come out and disengage the switch. A similar incident happened to me this morning;

http://www.katriders.com/forums/viewtopic.php?t=24477

he said his bike sputtered before dying. did yours? I am betting it didn't if it was the kick stand. It just stalled....maybe came back on if it toggled on/off.
the kickstand switch works the exact same way as the kill switch. I will give you a $100 if you can make your bike sputter with the kill switch, it will be off or on....no in between.

[Mojoe]

another thing to check is that a hose is not slightly kinked. a slightly kinked hose will cut fuel flow as well.

however, the cheapest and easiest fix is not to run at 110-115mph for 10-15 miles in the first place.