Vapor lock victory! Or, "Screw you, Mr. Pump"!

[Guest freud]

I have just tested out the the new fuel and air system on my v11 and everything is peachy! Thanks to the many great suggestions.

 

The lungs have been opened up and everything sounds great, what's more THERE'S NO HEAT PROBLEMS ANYMORE!!! Whoopee! Here's what I did:

 

1. Remore vaccumn canisters, and seal vaccum ports on intake manifold.

 

2. Remove airbox and replace with Emgo 52mm pods.

 

3. Flip fuel filter upside down and reroute fuel pump to top of spine frame.

 

And principally, that's it. I just pounded the bike today in 100 degree heat at 6000 feet and viola! it's done!

 

The one trick thing is the making of a S shaped aluminum tube to route the stock pump into the petcock.

 

Pictures will follow soon, and the bike looks SOOOO much cleaner and meaned with the side panels, and air box removed.

 

Now if someone can sell me those black Cobra pipes, I'll be done!

 

(deleriously happy) freud

[al_roethlisberger]

See.... "told ya"

 

 

 

 

 

....now, here's one further suggestion..

 

I'm not sure how you made the "S shaped aluminum tube" to reroute the fuel supply line, but take care here if you sorta "shade tree engineered it".

 

I can tell you from experience that if you did not make it from fuel/brake line tubing, and used the correct tools to bend it... and here the critical part.... made the appropriate ends to transition to the hose portion... you run a very high chance of the tube itself breaking from metal fatigue during bending, and caused by the vibration, and/or the end of the tube cutting into and breaching the hose at their junction. I only mention this, as I've had this happen.

 

If you made the tube with a flare kit, and have an actual fitting, or similarly made the correct roll at the end of the tube along with crimp, then you will be fine. But also be sure to isololate the aluminum tube from vibration as much as possible, because even in a best case, if it's left to move grossly, it may develop fatigue at the bends and crack.

 

If you didn't do the above.... then you can take your "prototype" down to a local hydraulic hose shop and have them make the "real thing" and it will be indestructable, or you can just go down to your local automotive "speed/hotrod shop" and buy some XRP/Earls/etc... "AN" fittings and make up the needed bends with the correct hose, and these will also be "indestructable". These are the red/blue fittings you see in my Fuel Pump Relocation Thread.

 

 

Anyway, great to hear our past experiments made this fix much easier for you to implement. I know it gave us a lot of grief, and were only able to "test" its efficacy to some degree. Your feedback provides even more validation

 

al

[Guest freud]

Actually, "I" diddn't REALLY bend the pipe myself as I am not in the know, but Pat from the Underground Terrorist Motorcycle Cult here in CO bent it for me. Thanks Pat. But yeah, real good suggestion kids, don't try this at home kinda thing (sorry) anyhoo.

 

But yeah, sorry I don't have the pictures up yet , I have worked over 75 hours this week, and spent the rest of my time riding. Thanks again, AL!

 

 

freud

 

And with the airbox and side panels removed, pods etc, IT LOOKS SOOOO SICK. Pant, pant, pant, sorry. God I freakin' love the way this bike looks .

[johamilt]

I have a question for those of you who have worked with gas tank problems: I ride a 2002 scura, and when I top off the tank, go home, then park it in the sun, gas begins to drip then just plain spill from under the tank onto the cylinder head. I don't know if this is related to vapor lock or tank suck or whether I have a cracked overflow hose, but I'm not the most experienced gearhead and I wanted to ask before fiddling with the tank.

 

I can tell you that the tank does get pressurized with temperature changes (in cool temperatures, air sucks in when opening the gascap, in hot temperatures it is expelled). Also, when the tank is down about a gallon, I don't have this gas dripping problem. Any ideas or experience with such a problem?

 

Thanks a million,

 

johamilt

[al_roethlisberger]

I have a question for those of you who have worked with gas tank problems: I ride a 2002 scura, and when I top off the tank, go home, then park it in the sun, gas begins to drip then just plain spill from under the tank onto the cylinder head. I don't know if this is related to vapor lock or tank suck or whether I have a cracked overflow hose, but I'm not the most experienced gearhead and I wanted to ask before fiddling with the tank.

 

Well, this part probably is simple overflow gas running out of the overflow or vent(if you've REALLY overfilled it)... and it sounds like your overflow line has come disconnected from under the tank.

 

Usually both of these are simply "push on" affairs, and can come off quite easily.

 

 

I can tell you that the tank does get pressurized with temperature changes (in cool temperatures, air sucks in when opening the gascap, in hot temperatures it is expelled). Also, when the tank is down about a gallon, I don't have this gas dripping problem. Any ideas or experience with such a problem? 

 

 

This sounds like you definitely have the "tank suck" issue, and you should remove the tip-over valve post-haste.

 

Do a search for "suck" in the title of a thread, and you should find a close-up photo or two of this valve if you aren't sure what it is.

 

....but it's a very obvious item, being the only 2 inch long black cylinder hanging in-line on one of the overflow lines from under the tank

 

 

And based on your report in the first section, I am guessing that the tank is becoming pressurized, and fuel is being forced past the closed cap somehow(or it's just sloshed fuel when the cap was opened) and running out of the overflow drain in the collar... again with no hose attached, or maybe a loose hose.

 

BTW, when filling a tank, I had been told.... and usually only fill the tank to the bottom edge of the neck/filler. This usually leaves a good couple inches of neck for expansion/slosh protection. This is a little less clear with the Sport tank, but just don't fill it all the way to the tippee-top.

 

al

[johamilt]

Thanks for the comments al, I've looked through some of the threads on tank suck and will try out that fix, as well as inspect the overflow hose. The previous discussions on tank problems you contributed to were very clear and helpful, it sounds like you know the "ins" and "outs" of the MG tank

 

again, thanks a bunch

 

johamilt