|Posted on Sunday, July 01, 2007 - 10:54 pm: ||
So I'm riding with some guys on jap bikes on some twisties and we stop to talk about where to go next. Nothing really aggressive. Anyway, we're talking over the engines and people start turning off their engines. I do the same but quickly find out that the conversation is over pretty much as soon as I click over the kill switch. They've decided where to go, start their bikes back up and ride away. I flip the switch back to run (my fan is on high), hit the start button, but the engine will not re-fire... Cranks but no fire. Battery almost goes dead and it miraculusly fires. My ego is a little hurt cause I was out-riding a busa and I was nervous cause it was at night on a country road.
Anyone else have this problem? Engine too hot? I know its not a gas problem cause its done it before on another tank of gas. Ideas, theories, fixes welcome.
|Posted on Monday, July 02, 2007 - 02:13 am: ||
Unless I'm full of beans, I'd chalk it up to operator error. Did you turn off the ignition switch and turn it back on before you hit the start button? If not, you may not have reset the fuel system to prime itself properly to insure ignition startup.
One of the standard things during startup is ensuring that the Check Engine Light comes on and goes out before hitting the start button. If the CEL did not come on because you used the RUN/OFF switch instead of the ignition switch, (and I'm guessing here) that probably caused the fuel pump to not prime resulting in cranking but not firing. Did you hear the fuel pump whine before hitting the start button?
It's just a theory, but if it turns out to be the facts, then just turn off and on the ignition switch next time, wait for the CEL to go out and you're good to go.
OTOH, you said it has done it before, so either you may have found a bug in the system or there is something amiss. Boy, if you did find a bug, that's gotta be worth at least 20% off your next Buell or an updated service manual, lol.
|Posted on Monday, July 02, 2007 - 01:53 pm: ||
well I don't think its vapor locked being that it cranked (i.e. not locked). I actually don't wait for the light to go out - I wait for the fuel pump to stop whining... which it did. I didn't touch the key. This is the sequence I followed:
- running fine
- stopped at stop sign toggled kill switch
to off (fan goes into high mode). Notice
I didn't turn the key here.
- approx. 10 seconds later toggled the kill
switch back to run
- wait for CEL to turn off (fuel pump
whines like normal
- I hit the start button and engine cranks
- hold in the start button for about 3sec.,
- hold start button down for 5sec. no fire
but kinna stumbles like it wants to start
- hold start button down till headlights
begin to go dim - FIRES!!
- no problems for the rest of the trip
Didn't know you have to toggle the key to re-fire that soon... thought if fuel primed it was okay.
|Posted on Monday, July 02, 2007 - 09:03 pm: ||
It seems like your procedure should have worked, all else being equal. Don't feel bad. I've had this hard starting business happen to my 9R a couple times when it's been really hot, so yours is not an isolated case. And I suspected vapor lock.
Maybe you misunderstood what I meant by vapor lock. That is a condition where the fuel goes from liquid to a gas (vapor) or a fancy word for bubble. It's possible that the fuel was so hot that it bubbled in the fuel pump/ fuel line/ injectors at that time. This could either cause the pump to cavitate (spin without creating pressure) or create pressure but a bubble prevented fuel from getting to the injectors. Does this make sense?
Vapor lock is a condition that more commonly afflicts autos that have a engine mounted fuel pump that sucks gas from the gas tank. This lowered pressure in the fuel line is a major factor in auto vapor lock situations when it's hot outside.
This is quite the opposite in our fuel injected bikes where the fuel pump pressurizes the fuel line; but if there is any chance that a bubble can form in the fuel pump, well then we've got trouble... at least until the fuel cools down a little.
A little advice for the next time? Wait until the fan speeds down to slow or goes off, then it should start right off. Maybe...
Thanks for the post.