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Discussion Starter #1
This has happened to me about 4 times now, and still haven't figured it out exactly. My best guess is vapor lock.

I have a 2012 XCT, everything is stock. Not long after purchase (<500 miles) I was in Denver, stop and go, and parked the bike. It was pretty warm, in the 90's, but not overly so. The bike sat about 10 minutes. When I went to start it, the motor wouldn't fire. I gave it a bit of throttle and finally got it to start though it sounded like crap at first until it smoothed out.

Last week I was in Chicago, it was a very hot/humid 100+ degrees. I stopped at a gas station to hydrate the wife and myself, but didn't fill up the bike. We each drank a gatorade (the humans, not the bike) and then got back on. Same thing as before, she (the bike) wouldn't fire. I hit the starter about 5 times before she fired and idled very rough, backfiring and running like crap until I got her revved up for a minute and it steadied.

A few days ago I was headed back to Colorado and was somewhere in Wisconsin. Again it was hot so I stopped to get a drink. Tried to start the bike and the same thing happened again. I popped the fuel lid right away to see if that helped and it didn't. I gave it a lot of throttle this time...enough to smell gas...and it finally started again rough idle until I got her revved up and then she ran smooth.

Any ideas? It sure acts like vapor lock, but I haven't seen any posts with a similar issue. I can stop in the exact same conditions with no issues.
 

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Maybe your fuel pump gets lazy and sweaty when it's too hot. :D

How many miles do you have on the bike right now?

Try tightening your battery connections, and test it out again. 50% chance you have a slightly lose connection, which gets worst with thermal expansion. I highly recommend doing this before pursuing any other possibilities.
 

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You've popped the cap so you ruled out venting and vapor lock is unusual on FI engines. About the last option I can think of is fuel and they may only be a problem if you've always fueled up at the same station. If this is the case try fueling at a different station.
 

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Vapor lock on a fi happens after a heat soak, it gets so hot that the fuel vaporises in the injector before or between pulses. I've had it happen on fi cars, it's got nothing to do with cracking the tank
 

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This has happened to me about 4 times now, and still haven't figured it out exactly. My best guess is vapor lock.

I have a 2012 XCT, everything is stock. Not long after purchase (<500 miles) I was in Denver, stop and go, and parked the bike. It was pretty warm, in the 90's, but not overly so. The bike sat about 10 minutes. When I went to start it, the motor wouldn't fire. I gave it a bit of throttle and finally got it to start though it sounded like crap at first until it smoothed out.

Last week I was in Chicago, it was a very hot/humid 100+ degrees. I stopped at a gas station to hydrate the wife and myself, but didn't fill up the bike. We each drank a gatorade (the humans, not the bike) and then got back on. Same thing as before, she (the bike) wouldn't fire. I hit the starter about 5 times before she fired and idled very rough, backfiring and running like crap until I got her revved up for a minute and it steadied.

A few days ago I was headed back to Colorado and was somewhere in Wisconsin. Again it was hot so I stopped to get a drink. Tried to start the bike and the same thing happened again. I popped the fuel lid right away to see if that helped and it didn't. I gave it a lot of throttle this time...enough to smell gas...and it finally started again rough idle until I got her revved up and then she ran smooth.

Any ideas? It sure acts like vapor lock, but I haven't seen any posts with a similar issue. I can stop in the exact same conditions with no issues.
http://www.victoryforums.com/showthread.php?t=11430&highlight=vapor+lock
 

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Cornfed,
I mentioned venting because there have been a few reports in the past of X-Bikes with fuel tanks that didn't vent properly. Vapor lock on FI has a little bit to do with the venting but doesn't happen often. This may have changed since the fuel formulas have changed, ethanol may cause fuel the vaporize faster which could lead to vapor lock.
 

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Discussion Starter #8
You've popped the cap so you ruled out venting and vapor lock is unusual on FI engines. About the last option I can think of is fuel and they may only be a problem if you've always fueled up at the same station. If this is the case try fueling at a different station.
Thanks. I've been traveling, so the same station is not the problem. I do try to pick name brand gas...Shell, BP, etc so I couldn't discount something in the gas per brand, though that seems unlikely.
 

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Discussion Starter #9
Maybe your fuel pump gets lazy and sweaty when it's too hot. :D

How many miles do you have on the bike right now?

Try tightening your battery connections, and test it out again. 50% chance you have a slightly lose connection, which gets worst with thermal expansion. I highly recommend doing this before pursuing any other possibilities.
Right now it's at 6500. This happened at under 500, and kind of randomly in between then and now. I would think thermal expansion would make the connection better! I will take your advice though and check the connections. It turns over just fine during this, just doesn't fire. Then after cranking several times it fires up with various throttle manipulation.

The odd thing is it's been just as hot other times and fired up just fine. It has never happened when I put gas in the tank but it's so random it's hard to say if that has any meaning.
 

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Discussion Starter #10
Vapor lock on a fi happens after a heat soak, it gets so hot that the fuel vaporises in the injector before or between pulses. I've had it happen on fi cars, it's got nothing to do with cracking the tank
Yeah every time it happened after a heat soak.
 

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How does the fuel pump sound when its priming? Do you hear one, constant tone, or do you hear two different ones, a low pitch buzz followed by a higher pitch buzz?
 

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Discussion Starter #12
How does the fuel pump sound when its priming? Do you hear one, constant tone, or do you hear two different ones, a low pitch buzz followed by a higher pitch buzz?
By recollection it sounded normal to me...constant buzz for a second or 2. I switch on the key first, I then turn on (or off depending on your point of view) the kill switch and hear the pump buzz and wait before hitting the starter switch. I can't be sure because I don't really pay attention to it, but I'd probably notice something out of the ordinary. I'll try to pay closer attention to it.

Do you think a change in tone indicates the pump pushing bubbles?
 

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Sounds like an injector problem to me...it only happens sporadically and after running long distances between stops. Check your plugs... i'll wager that one cylinder is running very rich and when you go to start it again, rather than "vapor lock" you are experiencing a flooded cylinder condition. Too much fuel at start up... then runs fine once started.
 
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