redxxrdr Posted May 9, 2011 Share Posted May 9, 2011 I could usually plan on 220 miles per tank when I first got my 01. Last month, I could only get 140 miles. So I started checking things. One thing that I found was a split vacuum line going to my cruise control servo. Not a Honda line, but one of the cheap ones provided with the cruise. I repaired that line, and I have gone from 28 mpg to 32mpg. Still not where I started, but a great start. I plan to check all lines including the PAIR lines when I get home with a empty tank. ( No Rich, I still haven't installed the PAIR bypass kit from two years ago. ) I am also thinking of going back to the OEM air filter instead of the K&N. I may be over oiling it. So a couple of questions. What size are the vacuum lines? I didn't see it in the book. Is there a benefit to buying silicone vacuum lines? I worry that the local autoparts lines are like the Chinese valve stems. Good for a year, then fail. Thanks, Craig Quote Link to comment Share on other sites More sharing options...
FiXXation Posted May 9, 2011 Share Posted May 9, 2011 Did your gas have ethanol in it when you first got the '01? Quote Link to comment Share on other sites More sharing options...
Furbird Posted May 9, 2011 Share Posted May 9, 2011 Did your gas have ethanol in it when you first got the '01? DING DING DING, We have a winner! Up until a year ago, there were a couple of gas stations that sold pure, 100% gasoline near me. 37-38mpg. Now, 32-33 mpg. Some progress, huh? Quote Link to comment Share on other sites More sharing options...
The Krypt Keeper Posted May 9, 2011 Share Posted May 9, 2011 I still get 40mpg with ethenol gas. would get 41 or 42 with non ethenol gas. Have have a K&N filter, Leo Vince slip-ons, and PC3 since about 3k miles on the XX. At 29k now. Quote Link to comment Share on other sites More sharing options...
EVLXX Posted May 10, 2011 Share Posted May 10, 2011 Frequently asked questions, Possible solutions are many, Results may very, ? Quote Link to comment Share on other sites More sharing options...
Hobicus Posted May 11, 2011 Share Posted May 11, 2011 Make sure you check the simple things, too, like air pressure in your tires. How many miles on your XX? The plugs are due at 32k on an 01, but I've usually done mine about every 25k. Quote Link to comment Share on other sites More sharing options...
redxxrdr Posted May 11, 2011 Author Share Posted May 11, 2011 Yes air pressure at 41psi. You taught me that at WIXX a few years ago when I rode up there on track day pressures. I have also checked for brake and bearing drag. Both seem OK. I changed my plugs origionally at 16K. NO I didn't read the inspect at 16, replace at 32. So I changed again at 48K. It was thirsty before the change out. There are a couple stations around that advertise NO Ethenol fuels. Not close to home, but worth the drive to try. I still ride like a old lady, so I figure there are other things coming into play. Quote Link to comment Share on other sites More sharing options...
willxx23 Posted May 12, 2011 Share Posted May 12, 2011 Not too far off topic but what does the OEM air filter go for these day's and does anyone have a line on them? Thinking about going away from the K&N. Quote Link to comment Share on other sites More sharing options...
ironmike Posted May 12, 2011 Share Posted May 12, 2011 Frequently asked questions, Possible solutions are many, Results may very, ? EVLXX is giving you an excellent hint - check the integrity of the Fuel Pressure Regulator diaphragm. Anecdotal evidence strongly suggests that ethanol laced fuel has an incremental and cumulatively deleterious effect on the diaphragm - even a mere pinhole will negatively impact fuel mileage. Once compromised the diaphragm will eventually fail. Any trace of raw fuel in any of the the vent lines is a corroborative symptom. The fix is to replace the FPR; easily done since the FPR is at the end of the fuel rail (right side). Quote Link to comment Share on other sites More sharing options...
EVLXX Posted May 14, 2011 Share Posted May 14, 2011 haha... Years ago... my MPG was dropping, and I was struggling to figure out why. I checked to vacuum lines for residual fuel and found none. Changed plugs, air filter, etc, and still my fuel mileage was down and dropping. Normally I average 42-44 around town, and I was down to a constant 33-35, which was pissing me off. So finally I broke down and just replaced the FPR. The result was instantaneous, I was right back up to 42-44 mpg. You could do a search on the effects of ethanol and rubber, and you would find more garbage talk that one can handle. And if you look really hard you'll start to find how all of the Ethanol resistant fuel line products are just that.... Resistant... to the effects of ethanol, but over time they will also fail. Over time, the FPR diaphragm can get a little swollen, thus increasing it resistances to flexing and opening at the proper psi rating. The result is more fuel in constantly sprayed into the engine..... and you probably have a really black sooty buildup on your exhaust pipes. Since the Bird has a Open loop Fuel injection system, it cannot adjust for this added pressure, most cars on the other hand are closed loop systems and can adjust, hence why you don't see this problem all the time in the automotive world. Quote Link to comment Share on other sites More sharing options...
redxxrdr Posted June 1, 2011 Author Share Posted June 1, 2011 Well I just got in a Turbo City FPR. So I grabbed a flashlight and lifted the tank to see what it will take to change it out. A different light, at a different angle found another split vaccum line in the cruise circuit. So I have replaced it, and will run a tank through it to get a new baseline. Then I will try the new FPR. Too dark tonight to get my calipers in and measure the OEM line sizes. The bike is now ten years old. Figure I should replace all the lines while I'm in there. Quote Link to comment Share on other sites More sharing options...
Zero Knievel Posted June 1, 2011 Share Posted June 1, 2011 Not too far off topic but what does the OEM air filter go for these day's and does anyone have a line on them? Thinking about going away from the K&N. OEM filter from any fair dealing Honda shop is $40. I get about 2 year's use out of one. On odd winters I gently brush out any debris from the intake side and clean out the airbox. I only do this because I find the K&N costs me a touch more in gas mileage, but I saved the K&N in case I ever want to go back to it. Of course, my PCII is programed to produce maximum gas mileage, so there's no incentive to go aftermarket on filter and pipes. Quote Link to comment Share on other sites More sharing options...
willxx23 Posted June 1, 2011 Share Posted June 1, 2011 Not too far off topic but what does the OEM air filter go for these day's and does anyone have a line on them? Thinking about going away from the K&N. OEM filter from any fair dealing Honda shop is $40. I get about 2 year's use out of one. On odd winters I gently brush out any debris from the intake side and clean out the airbox. I only do this because I find the K&N costs me a touch more in gas mileage, but I saved the K&N in case I ever want to go back to it. Of course, my PCII is programed to produce maximum gas mileage, so there's no incentive to go aftermarket on filter and pipes. So $30.36 from Chaparral Motorsports would be a great price on one. No shipping needed as I will have a nice reason to shop around their store. Quote Link to comment Share on other sites More sharing options...
redxxrdr Posted June 4, 2011 Author Share Posted June 4, 2011 An update with the vacuum lines fixed, and the old FPR. Mileage is now around 40 mpg. Up from 28-30. These are 1 tank measurements, so they are not real accurate. However a 10 mpg gain by fixing leaks is good. I have silicon hose coming. I had measured the vacuum fitting on my new FPR and it read 4.49mm. I ordered 4 mm hose. Hose and FPR will get changed next week. I will post up what I see after these changes. Quote Link to comment Share on other sites More sharing options...
EVLXX Posted June 5, 2011 Share Posted June 5, 2011 Can I have your Old FPR ? ... And secondly... now you have got me wondering ... Why the vacuum line problems.... and Hmmmm... maybe I need, check mine really well. Quote Link to comment Share on other sites More sharing options...
redxxrdr Posted June 6, 2011 Author Share Posted June 6, 2011 Can I have your Old FPR ? ... And secondly... now you have got me wondering ... Why the vacuum line problems.... and Hmmmm... maybe I need, check mine really well. I can send you the old one once I install the new FPR and test a little bit. PM me a address. Also my OEM lines are stiff, but holding. I have a Audiovox cruise control installed. It was the additional lines supplied with the kit that are cracking. But the OEM stuff is really stiff, which in my experience means it's time to replace them. Quote Link to comment Share on other sites More sharing options...
EVLXX Posted June 6, 2011 Share Posted June 6, 2011 agreed about the stiff lines... good call. will send PM. Quote Link to comment Share on other sites More sharing options...
Dano Posted June 20, 2011 Share Posted June 20, 2011 Have you replaced the FPR yet. I too have been grumbling about poor mileage as of late. 2002 stock motor no mods. 41K miles, MPG down to about 27 around town. db Quote Link to comment Share on other sites More sharing options...
tomek Posted June 21, 2011 Share Posted June 21, 2011 An update with the vacuum lines fixed, and the old FPR. Mileage is now around 40 mpg. Up from 28-30. These are 1 tank measurements, so they are not real accurate. However a 10 mpg gain by fixing leaks is good. I have silicon hose coming. I had measured the vacuum fitting on my new FPR and it read 4.49mm. I ordered 4 mm hose. Hose and FPR will get changed next week. I will post up what I see after these changes. I dunno about that 4mm , it might not be tight enough . As a matter of fact old rubber lines are of 3 mm I.D. I redid my vacum lines , all of them , today . They were totally fucked , audible hissing , relatively shitty in city fuel economy . It is a reference fpr , so under light load fuel pressure should drop . If there is vacum leak you end up with richer AFR - fuel economy sinks especially in light load situation . Quote Link to comment Share on other sites More sharing options...
JoWhee Posted July 19, 2011 Share Posted July 19, 2011 So I'm having a similar problem, I spent the day yesterday checking out all the vacuum, and PAIR lines, all good except the breather line at the front of the airbox (PCV?) wasn't connected, would it make much difference? I've already changed out the FPR and air filter. And run a can of seafoam through 2 fillups. I've even reverted to the stock exhaust. Quote Link to comment Share on other sites More sharing options...
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