I could use some insight regarding a fuel line issue I've got. I walked out and cranked the bike this morning and discovered fuel dripping where the lower right line coming from the airbox meets the "T" connecter to the carb. The woven black line looks frayed at the connection, so I dried the leak and wrapped the connection in gorilla tape until I can get the parts tomorrow (Blue Moon and BMW of Atlanta are both closed on Mondays). My Clymers manual is on it's way, and I'm not comfortable taking the air box apart to get the fuel line out before I've got the guide telling me what to do. I searched and found a thread from 2008 about a R100GS fuel line replacement, but I don't think that'll help me. Has anyone had any experience with this? Should I just go hit up the BMW shop for more fuel line or is there a better aftermarket option? Anything I should know before I make this repair myself, or should I let the professionals do it? Thanks very much for the help. The location of the leak, wrapped in tape to keep it from dripping on the block:
Right first things first..... DO NOT pull out the old fuel line before attaching the new one! otherwise you will need to strip the airbox etc (don't ask how I know this) I use clear yellow Lectron racing fuel lines on my R80, much better than the stock fuel line. They use it on aircraft, go carts, race bikes etc. back to your fuel line, thread some wire through you old hose, and through the new hose, and then feed the new hose in as you pull the old hose out. http://www.lectronfuelsystems.com/products/fuel_line.html Kevin.
Replace your fuel lines, they don't last forever, and failure can have disastrous results! If you want to be belt and suspenders about it, use clamps too. BMW sells hose clamps that have a lip that prevents them from cutting into the fuel line. The cheap screw type can cut the hose. I've had mixed luck with using something to pull the new hose through the airbox. It's not that hard to pull the cover and do it right. Besides, when's the last time you checked your air filter?
It is not that big a deal to remove the air box to replace that fuel line. Go ahead and try to do it with out taking the box apart but if you have to have no fear. There is a trick or two you will need to know about getting it back together but that is all. First off a little information about the line used on Airheads. It is an odd size, it is metric. It is the same size and material used on vintage Volkswagens so apparently you can get it at shops that deal with the older Beatles. This fuel line is 7mm. You will find 8 mm which is too big and 1/4 inch which fits tight. Either of these can be made to work but I don't like the look of a bunch of hose clamps I had to use with 5/16 (otherwise known as 8 mm) and when using 1/4 line it is impossible to remove should you need too. I have used 1/4 in emergencies. I must admit I prefer the fit and the look of the correct 7 mm braided fuel line. The OEM fuel line will eventually leak because of the Gasohol we are burning in our engines. Gasohol is also causing troubles with carburetor O-rings and possibly diaphragms and floats. All of these parts were always renewable but we are having to tend to them much more often today than before. I think England Kev might be right. I should use the modern stuff that lasts longer. But I'm not aware that this is available in 7 mm. I guess I could learn to live with 1/4 if I had too. There are two tricks, either one will suffice, to get the air box back together. One...The left side carb air intake was removed to take the left side of the box off. You may do this without taking the carb itself off. The problem is getting the long screw back in. Shine a Flashlight in the air feed part of the Aluminum box and you can watch the screw to see it is in the hole. That usually works for me..Two....Sometimes it is still not happening so if you take the air tube off the right carb you can reach a couple of fingers in the box to guide the screw. When messing with these air tubes and the carbs it's best to loosen all the tube clamps a little so you can twist things around a little to get the tub off. Just have everything lined back up to tighten the clamps again. Messing with this part of the motorcycle will come up often so you might as well learn early what's going on. Take your time, don't rush. Have the bike of the center stand for these operations. The carbs should end up either perfectly flat or even once the clamps are re-tightened or they should be tilted in a small amount. Bing sells some Alcohol Resistant fuel line but I'm not familiar with this product or if it is the same stuff that EK mentions.
I have been using Lectron on my R80 since the day I bought it, no need for clips, it doesn't go hard or brittle, and being clear you can see the fuel running through, I am about to order some for my Guzzi, I will order a bit extra and send some to you, so you can have a play with it, I think you will be convinced. Drop me a PM with your addy, and I will get some in the post. Here it is in situ, as you can see it is a nice tight fit, but pulls off without the need for tools.
It looks like 1/4" SAE fuel hose is used in your photo. 1/4" SAE fuel hose is available at any auto parts store. Other than aesthetics, the 'official' BMW braided cover fuel line is inferior in strength, abrasion resistance, and costs more. Attaching the new hose to the old an trying to pull it through the air filter housing is a good idea, otherwise the left air filter cover needs to be removed per replacing an air filter. I would go get ~ 4ft of 1/4" fuel hose from the local auto parts store, but some people find the BMW braided cloth cover fuel hose looks more official. Good luck!
Lectron? Where is it available? Personally, I have never found a clear line that doesn't get hard as a rock real quick. In my experience american sized line is either too small or too big. Woven BMW line is NLA. Some woven line is crap. For instance, since woven line is NLA from BMW, I worked at a well respected dealership that sold woven line sourced from Worth. It was and still is crap. Woven gas line looks more official? I get Made In Germany woven line through VW. Why? Because I think it is the best gas line out there. You can take it off and on for years and the line stays soft. Some gas on it to swell it up and it comes right off. Same with going back on. When the ends do eventually become too frayed, just cut off a quarter inch and put it back on and it's like new all over again. Other than cheap imitations, I do not understand how BMW woven line got such a bad rep on the net.
I use a line from Motion Pro, not cheap, but resistant to all the crap they put in fuel these days. Fits Perfect. http://www.motionpro.com/motorcycle/tools/category/motion_pro_premium_fuel_line/ Take a look
England Kev, You're the nicest guy and a good mechanic too. I've been missing the thread of your resurrecting the single cylinder Manx Norton. I used to follow you on that regular but then we split the Airheads off and only yesterday I got the itch to read some more about the Old's Cool. I think this was about a year ago? Those of you who haven't seen EK's thread on his Norton should check it out. It's looking much better than the photo I borrowed. But I can't accept your most generous offer. Those lines are Yellow. They don't have cloth covers. Charlie
You guys are awesome! Thanks a bunch for the help. I'll post some photos of the job once I get the stuff I need.
For those on this side of the pond interested in the yellow Tygon fuel line, McMaster Carr sells it: http://www.mcmaster.com/#5552K25 I have some 1/4" SAE fuel hose that has been on the bike ~ 20 years running through the air filter housing with BMW braided cloth fuel hose to the fuel petcocks. I plan to replace the SAE fuel hose with the same before long.
In lieu of project photos, I'll post a glowing review of BMW Motorcycles of Atlanta. I went over today to get some in-person advice on the fuel line leak before I picked up parts and set to the job of replacing the line. The guys in the service department told me they could take care of it for me in no time. Since I didn't yet have the Clymers manual, I let them do the work. It was done quick and because I'd recently bought the bike from them, there was no charge. Great folks over there, super nice and they took good care of me. If you ever find yourself in ATL, stop by and get a t-shirt.
