V11 Stalled Won't Start

[Lawrence]

Out riding my 2000 V11 Sport today, filled up with fuel and rode 20 miles on state highway, bike running great, stopped for a drink, got back on started off and bike died. Sputtered like it was struggling to get fuel, but would not start. A couple of more attempts got a bit of firing when choked, but then that stopped.

 

Stymied! Any suggestions on where to start diagnosis? I'm thinking fuel pump...?

 

Any suggestions would be appreciated!

 

Lawrence

[jrt]

vapor lock? It was a common problem on some early models.

Let it sit until completely cool, then try to restart.

[Lawrence]

vapor lock? It was a common problem on some early models.

Let it sit until completely cool, then try to restart.

 

 

Funny you should suggest this! I just went out in the garage to check for fuel pump priming, (it's been about an hour and a half since it stalled). The pump priming sound was normal, tried to start, and it started right up!!

 

Is there anything I should do to try and check this out more, or simply chalk it up to vapor lock? I've had the bike since last September, it had 7500 miles, 1500 of those are mine miles and with no issues what so ever.

 

Lawrence

[Lawrence]

I just read the "Vapor lock" string... That was me!! EXACTLY!

[jrt]

Great- I think...

OK, well, I don't know if it can be "fixed", but at least it can be mitigated pretty well. Someone on this forum (sorry, I forgot whom) sent me a piece of insulated pipe from some aerospace application. Rubber on the outside, fiberglass inside. Slip it over the fuel intake and it's supposed to fix the problem. I haven't tried it yet, but you might be able to get the stuff from McMaster-Carr. Look for about 1/2" internal diameter. I'm working on (questionable) memory here, so you probably should measure the OD of your intake.

I'm glad it's nothing major. Just a PIA.

[Lawrence]

Great- I think...

OK, well, I don't know if it can be "fixed", but at least it can be mitigated pretty well. Someone on this forum (sorry, I forgot whom) sent me a piece of insulated pipe from some aerospace application. Rubber on the outside, fiberglass inside. Slip it over the fuel intake and it's supposed to fix the problem. I haven't tried it yet, but you might be able to get the stuff from McMaster-Carr. Look for about 1/2" internal diameter. I'm working on (questionable) memory here, so you probably should measure the OD of your intake.

I'm glad it's nothing major. Just a PIA.

 

 

Thanks for the insulation tip! Lawrence

[Kiwi_Roy]

You have me curious, I replaced all the hose on mine last year and left off a great wad of insulation the PO had applied.

Please point us to the vapour lock thread

[Lawrence]

You have me curious, I replaced all the hose on mine last year and left off a great wad of insulation the PO had applied.

Please point us to the vapour lock thread

 

Here is one, but not the one I was looking for.... I'll post the other as soon as I find it again:

 

http://www.apriliaforum.com/forums/archive/index.php/t-233472.html

[Lawrence]

You have me curious, I replaced all the hose on mine last year and left off a great wad of insulation the PO had applied.

Please point us to the vapour lock thread

 

 

Hey Roy, Here's the link I was looking for:

 

Vapor Lock

[Skeeve]

Is there anything I should do to try and check this out more, or simply chalk it up to vapor lock?

 

Vapor lock, for certain. All the external fuel-pump models are susceptible to it. Symptomology is exactly as you described: nice, spirited ride on a warm day to get the motor hot, stop the bike for longer than a quick fuel stop & let the fuel lines get heat soaked, & the bike fails to start. Once everything cools off, it's back to normal, no signs of failure.

 

Only thing that can be done is either: A] Swap the fuel tank & pump for the late model one (where the fuel pump is inside the tank to keep it cool & protected from the heat off the motor) - expen$ive! or B] try to insulate the fuel pump & attached lines as well as possible with appropriate materials (there's stuff out there in meat-space that you can use for this: check with homebuilt airplane supply catalogs like Aircraft Spruce or racing car parts places like Summit, JEGS, etc. for hi-temp insulation.)

 

Best o' luck to you!

[Lawrence]

Is there anything I should do to try and check this out more, or simply chalk it up to vapor lock?

 

Vapor lock, for certain. All the external fuel-pump models are susceptible to it. Symptomology is exactly as you described: nice, spirited ride on a warm day to get the motor hot, stop the bike for longer than a quick fuel stop & let the fuel lines get heat soaked, & the bike fails to start. Once everything cools off, it's back to normal, no signs of failure.

 

Only thing that can be done is either: A] Swap the fuel tank & pump for the late model one (where the fuel pump is inside the tank to keep it cool & protected from the heat off the motor) - expen$ive! or B] try to insulate the fuel pump & attached lines as well as possible with appropriate materials (there's stuff out there in meat-space that you can use for this: check with homebuilt airplane supply catalogs like Aircraft Spruce or racing car parts places like Summit, JEGS, etc. for hi-temp insulation.)

 

Best o' luck to you!

 

 

Thanks Skeeve!!

[rex007can]

You did replace the stock relays right?

[Kiwi_Roy]

Thanks for the Vapour Lock link, my buddie and I are planning a trip to California in August, I'm sure it's much warmer than here in BC so I will put some insulation back.

I/m guessing the fuel boils right at the pump suction since rubber is such a good insulator.

 

Just out of curiosity I looked up gasolene boiling point.

http://www.engineeringtoolbox.com/fuels-boiling-point-d_936.html

It was explained to me that the wide range of boiling points is due to the different components, Im guessing that only one or two of the lower temp ones need to flash off to cause a bubble.

[Buzzard]

I went with the pump relocation choice on my 2002. The stock pump is too large to put any place else, as is the filter. I found a pump made by MSD, the ignition people, which is intended for FI motors installed in kit cars. While quite small, it works well enough to feed a 600HP V8. Behind it I mounted a filter recommended for this pump, a beautiful machined finned aluminum affair with a serviceable element. All of this was small enough to mount on the LH side on a frame rail beneath the seat. While at it, I went with velocity stacks and K&N filters. I live in mountain country, altitude worsens the vapor lock problem. I have about 20K miles on this setup with no further problem.

[Night Rider]

I got a bike with an external fuel pomp but another setup I haven't seen on any other V11. Not sure if it's factory default or the previous owner changed it that way. Basically the oil cooler is lowered to where normally the voltage regulator is placed on other bikes and the fuel pump is placed above the oil cooler with some heat shielding. The horns are also on top of the oil cooler and the voltage regulator is placed behind the oil cooler.

 

Never had any vapor lock problems so far.

 

Is there anything I should do to try and check this out more, or simply chalk it up to vapor lock?

 

Vapor lock, for certain. All the external fuel-pump models are susceptible to it. Symptomology is exactly as you described: nice, spirited ride on a warm day to get the motor hot, stop the bike for longer than a quick fuel stop & let the fuel lines get heat soaked, & the bike fails to start. Once everything cools off, it's back to normal, no signs of failure.

 

Only thing that can be done is either: A] Swap the fuel tank & pump for the late model one (where the fuel pump is inside the tank to keep it cool & protected from the heat off the motor) - expen$ive! or B] try to insulate the fuel pump & attached lines as well as possible with appropriate materials (there's stuff out there in meat-space that you can use for this: check with homebuilt airplane supply catalogs like Aircraft Spruce or racing car parts places like Summit, JEGS, etc. for hi-temp insulation.)

 

Best o' luck to you!