| Author | Message | ||
     Bigeasy |
My bike Icould swear has the same thing happen as yours jdugger. I am in new orleans 80 here also. I love the bike and the only problem I can forsee is HEAT. Wow does she get hot!!! Also why does the fuel pump keep going off well after shutting the bike off? | ||
| Bigeasy |
Same thing here Jdugger. I am in new orleans, 80 today. Why does the fuel pump keep going on well after the bike is off? | ||
| Bigblock |
My bike HAD a fuel boiling issue, it so far has not seemed to repeat this since the new vent system. If I was experiencing a repeat of this problem, I would take it back in to the dealer, as this does not seem OK to me... If I was having your guys problems of a real hot bike AND boiling fuel, I would definitely take it in, if I were you! That definitely seems wrong to me... If there is some sort of problem like this going on, Buell needs to know... | ||
| Tsrf900r |
I am not sure if we all have the same problem, but the temperature here is 33-40F. The bike smells after any ride over 30 minutes. If it gets worse as it gets warmer, I might need to install permanent exhaust fans into my garage...  | ||
| Zac4mac |
Fuel smell - bottom of frame/tank is hot from engine. Fuel boils some, I heard it. Top of frame/tank is cool/cold. The most volatile parts of the gasoline evaporate, then condense at the top. My fuel cap was wet, but my vent line was dry. If it's enough of a heat difference between bottom and top, a significant amount of fuel will condense at the cap/vent. Lower fuel level will exacerbate this. If the vent line doesn't do its job, pressure will build from the boiling/evaporation. There was no pressure released when I opened my gas-cap. Fuel smell is not related to an overfull tank. Guess we're not the only ones - http://www.klr650.net/forums/showthread.php?p=2917 83 Zack | ||
| Spectrum |
I've seen the fuel boil in my bike as well and as Zack pointed out it seems worse when the fuel is low. I also think this may be related to running it hard and then parking while there is a lot of heat in the engine. Once you shut it down the heat is going to continue to rise for a few minutes. With the cooling system shut down and no air flow the heat will build/peak much higher than with the bike running. I've started treating her like a spirited race horse. After hard runs, she needs a little cool down jog before putting her away in the stable. In other words don't run her hard and put her away all lathered up.  | ||
| Zac4mac |
Ford tractors boil gas. http://www.ytmag.com/nboard/messages/606131.html ST13 owners - http://www.st-owners.com/forums/showthread.php?t=1 5306&page=3 Triumps - http://www.triumphrat.net/the-rocket-science-forum /52352-boiling-gasoline-anyone.html Looks related to current "oxygenated" fuels. Maybe I'll see about heat-shielding, but it's a lot lower priority than finishing my axle-sliders. Zack | ||
| Ratbuell |
From what I understand (one of our techs just went to class) the fuel pump cycles after shutdown to help equalize the tank pressure, not to keep the rail under pressure. | ||
| Zac4mac |
Keeping the fuel rail under pressure makes sense. If it's hot enough to boil fuel in the frame, it's probably hot enough to vapor lock the rail. Especially if the pressure drops. Using the fuel pump to "equalize pressure" doesn't make sense to me. You always have very good info, Joe, could you get the tech to elaborate on the hows and whys? Thanks - Zack | ||
| Jpfive |
I will relate what the Buell factory tech told me in Pensacola. The fuel pump will continue to cycle for about twenty minutes after shutdown, not to pressurize the tank, but to keep pressure in the rails. The purpose of this is to help in warm starts by avoiding vapor lock. The twenty minutes is an approximation, as the fuel pump cycle is determined by a temperature reading. Which sensor it refers to, I do not recall. He also told me that BMC is not the first to do this, that he thought it not uncommon in modern EFI systems. Appropriate disclaimer - I am not the designer of the system, but this is a faithful recollection of what I was told. Jack | ||
| Jpfive |
We have already seen one link to threads re boiling fuel in other bikes. I lurk in a lot of brand specific forums, generally as I become interested in a particular bike, or just out of curiosity. This is not an uncommon subject, in my experience. I suspect that reformulation of gas has played some role in this, especially as it varies so much now from region to region and season to season. I live in Florida, ride about 1000 miles a month, most of it locally. I have never experienced this phenomenon myself. One habit I have is to nearly always fill my tank before parking my bike. I fill it until it just laps the inner ring on the low (sidestand)side. The five mile ride to the house settles it a bit below that. I have used this procedure on all of the bikes I have owned. This procedure puts relatively cold-soaked fuel in the tank during the time that the bike is cooling down. I enjoy having an adult beverage on the patio as my bike cools down from the ride - enjoying the sight of it, savoring the ride a little longer, and enjoying the sounds and smells of the bike, including the smell of fuel. I consider it normal on a bike, as all of my bikes have had this in common. Maybe we're making too big a deal of this. Jack | ||
| Spectrum |
+1 What Jack said. I've never had the fuel smell, but I enjoy the smell of hot metal! | ||
| Dtx |
Jack, That's a good idea. I will make a habit of putting the bike away with a full tank of fresh, cool gas. In my short experience with the bike, I have only noticed it when the fuel level was low. Thanks! | ||
| Tsrf900r |
I'm starting to think some people have different problems. If you smell a little fuel after a ride, yeah no big deal, thats a bike. If you park you bike in the garage, and come back in 30 minutes, open the door, and enter a gas chamber where you cannot even breath. Yeah that's my problem. I am sure if I light a match, the whole place would go boom. Can't be normal. Can't be safe, and so far Buell doesn't care. At least not in my case. | ||
| Dtx |
Well, I just got back from a good 50+ mile ride. Temps were in the upper 50's so I bundled up and headed out. As I was heading home the fuel light came on so I stopped at the station and filler her up about 5 miles from the house. Rode home, parked it in the garage and observed a few things. The bike was still good and hot (operating temp). 1. No Boiling Fuel. 2. Frame was only warm and could be touched with a bare hand. 3. No Fuel smell as of now...I'll check again in about 30 min. I think Jack is onto something here. | ||
| Dtx |
OK, I went and checked on the bike in the garage. There was a faint smell of gas, but not bad. The frame was actually a little warmer then before and heard some mild bubbling coming from the frame. Opened the tank and confirmed this with my ear. The overflow vent hose was only damp to the touch and had not dripped anything like it has done before. I think from here on out I'll just fill her up on the way home and call it good. Unless anybody else comes up with something. | ||
| Cmonkey |
My 2 cents: I don't have my bike yet, but I think I see a pattern. (for bikes without any mechanical issues) Low tank: It's easier to boil a gallon of gas vs 5 gallons of gas. Full(er) tank: Long ride, hot frame, add gas, ride some more = adding more thermal energy to the gas. Park and there may be enough heat left in the motor to get the fuel boiling. It just depends on how much heat your fuel has collected. So some one may want to try this. After riding, filling it up, and parking it; point a fan at your bike to help dissipate the heat. Hopefully that'll curtail the evaporation/condensation and fuel smell issues. Personally, I'll probably do a couple of things when I get my bike... 1. If there's room, I'll put reflective insulation on the inside of the frame. 2. I'll stick one of those vornado fans on either side of the bike to keep some airflow going under the frame. that should keep most of the heat from being transferred to the frame/gas. (2hrs on a lamp timer should do it.) Or 3. (the wife would kill me) Keep a few gallons of fuel in the freezer, and fill up when I get home! On a side note, I've been trying to find out the boiling points of the different fuels in my area (Chevron, Shell, winter vs summer blends, etc). So far I've only found the specs from my local race fuel supplier. Dave | ||
| Tijuanajack |
Hello all, Just did my service on Saturday as some of my buddies were going riding on Sunday with a local group of riders here in Augusta, GA. We Stopped a a fuel station to wait for a few more riders. I accidently overfilled my tank and went over lip inside the tank. We were parked for a while and then started our bikes to start the ride. Another rider noticed my bike dumping a fluid on the ground which was fuel as the ignition was on. I noticed that it was from the overflow tubes which are the same ones that vent the tank out when it gets hot. Someone posted earlier about checking the vent line under the airbox bottom. If that hose is pinched or broken it will cash back pressure in you frame tank and cause your bike to run funny. The reason the bike smells like fuel after a ride is because the fuel injection system cycles the fuel through and at the same time pushes the fumes out of the tank through the overflow tubes that exit right by the muffler where the header tubes meet the muffler. This is what I have noticed. | ||
| Unibear12r |
Pumping fuel around for twenty minutes would tend to make more fumes. I would think it would make more with a hot and low fuel level too. Could all or part of the "boiling" be fuel returning to the tank? Someone posted (I think) that the "boiling" was at the low right side which is at the fuel pump. Where's the return? Jack could be on to something here between the fuel formulation and the fuel being cycled after shutdown. | ||
| Spatten1 |
Cmonkey: Good point on the physics. If you fill the tank right before coming home, it will cool the frame and fuel off, with gas from a cool underground tank. | ||
| Cmonkey |
Thanks, but not my idea. Got the AHA from Dtx's post. From all the posts, there seems to be a general issue with heat transfer to the frame/gas AFTER riding. Aside from the fuel issues due to pinched hoses and flooded canisters, the frame and gas are acting like a heat sink. The problem I can see is if the frame and gas soak up too much heat during a ride, then it won't take much to get the fuel boiling after you park it. I had a similar concern with my car, I'd park it after a hard drive, and after a while you could fry eggs on the hood. Although my gas was in the back, I was concerned about how long my paint was going to last. Once I added the reflective insulation, no matter how hard I drove, I could put my hand on the hood anytime without getting burned. So whomever is having trouble with that last gallon or two boiling after a ride; point a fan at your bike after you park it and see if it stops the fuel from boiling. (and let us know) I'll bet we'll see some strategically placed bits of reflective insulation on bikes in the future. Another thought is that fuel boiling shouldn't be that big of a deal, as long as the pressure doesn't get too high. The fuel should act like those tree ornaments that have the bubbling fluid in them. The light heats up the fluid, it boils to the top and condenses. Hopefully the tank vent system can keep enough pressure to allow for the condensation of the fuel, and the top of the frame can dissipate enough heat, but as with any closed system, too much heat and pressure and bad things start to happen. Hopefully BOOM won't be one of them. Note to self, don't talk about leaving the lava lamp on the stove!  | ||
| Dtx |
I'll do the fan trick after my next ride. Also, do you know where to find some of this reflective heat insulation? | ||
| Dentguy |
Be careful about filling the tank up before parking it. Too much and that cool fuel heats up and pushes out the overflow/vent while sitting. Did it on my Uly. (Message edited by dentguy on March 17, 2008) | ||
| Cmonkey |
The stuff I got was similar to this stuff: http://users.cwnet.com/~thall/insulato.htm I can't remember my original source (at it's long gone). But you'll want to use foil tape instead due to the tight clearances. The thicker padding will probably cause airflow problems. Just line the inside of the frame with a couple of layers of heat resistant aluminum foil tape like: 3M High Temperature Aluminum Foil Tape #363 or #433 Here's the specs: http://www.mpsupplies.com/3mtape363.pdf This is the way I plan on going. Line the inside of your frame with this, and it should stop a lot of the heat transfer. My only concern would be how much heat it would reflect back on the engine. I know I'll probably use the reflective tape in conjunction with a fan after riding. I'll probably lay down a patch on the frame closest to the engine (maybe 3-4 inches square). See how it affects the rolling temperature and the after ride heat transfer. I'll keep making the patch bigger (and or thicker), and stop if the coolant temp starts to run hotter. Then keep on using the fan after rides. I have lots of lamp timers left over from xmas so running a couple of fans a couple of hrs/night is no big deal. (Message edited by cmonkey on March 18, 2008) | ||
| Dtx |
I took a closer look at the rear cylinder/rear header area. First I removed both heat guards. The one on the header and the black one that is supposed to stop the baked right foot. I was able to see whats all going on back there and noticed that the headers have a fair amount of room. However, there is one area where the header is closest to the frame (about 1/2" or so). Ironically, this is the area where the pipe comes out the side of the motorcycle frame, which is exactly where the Black Foot Barrier was added. I am wondering if the Black Foot Barrier is actually redirecting heat inwards, thus causing the boiling fuel. Regardless, I think a some strategically placed heat barriers (insulated heat tape) could keep the frame cool enough to prevent fuel boiling at this location. | ||
| Dtx |
Another update. Rode it again tonight and warmed it up completely. Got home, stuck a fan on the right side of the bike and am happy to report no boiling fuel, no fuel smell, no problem! | ||
| Cmonkey |
That's good news. Now the trick is to find some of that high temp tape and see if putting a 4x9 inch patch on the insides of the frame help to point where you won't need a fan. | ||
| Dtx |
Not sure if anybody else is still tracking this, but I have collected a little more data. It seems that the annoying little fan we had on our XB's was doing more then meets the eye. It was probably keeping the heat off the frame as well. With temps in the low 70's I went riding tonight. Got back and could hear the fuel boiling in there. Put a fan on the bike and within minutes the fuel stopped boiling. I also borrowed a laser pointing thermometer from work and checked some temperatures after yesterdays ride. Lower Frame - 120's (Could touch with hand) Headers - About 200 degrees (thought this would be hotter) Rear Cylinder Area - 225 to 250 degrees Muffler - 250's All in all, I doesn't seem that any of these components are getting real hot. I didn't know what to expect but was surprised at the seemingly low temps. I guess the rear frame area is getting just hot enough to boil the fuel, as a fan stops it almost immediately. The boiling fuel doens't really bother me as much as the gas fumes it puts off through the vent hose while its happening. Plus it does drip fuel on the muffler. That's not going to look real good at a track day having fluids spitting out, even if it is just fuel vapor condensation. Not sure how to explain that one if it comes up at tech inspection. | ||
| Cmonkey |
I found an alternative to the $200/roll 3m tape. Get some of this and pad the areas that seem to be getting the most heat. http://www.partsamerica.com/productdetail.aspx?Mfr Code=DEI&MfrPartNumber=010408&CategoryCode=3638G David | ||
| Jpfive |
Thanks for the link, cmonkey. I've got some of that tape on the way. Jack |
