Bruckner Posted September 19, 2016 Share Posted September 19, 2016 Hey guys! My VFR has been in storage for nearly a year when I finally decided to start it up for a few rides. I think my beloved VFR, which I've owned without the slightest issue since 2007, didn't appreciate being left out of action for so long! It now has about 50,000 miles. The bike idles roughly, with the RPM needle fluctuating abruptly between 1,000 and 1,500, and the motor hesitates on soft acceleration in first gear, almost imperceptible in second gear and totally fine in upper gears. Riding in town is awkward and unpleasant. With more throttle, I can't feel any jerkiness though I can sort of hear very brief interruptions in firing, though I'm not trained to qualify this as a misfire. I get none of the more frequent steady throttle issues that many report about. Once on the move, it's fine. The bike has been running the same mods since I got the bike all these years (and roughly 40,000 miles) ago: LV pipes and K&N air filter. The O2 sensors are still plugged in, no powercommander or anything the like. At first I thought it was bad gas, after all the bike had been sitting for nearly a year (I had seafom in a full tank of gas prior to storing, supposed to act as fuel stabilizer), but after nearly emptiing the tank and filling with fresh gas, it still runs rough. Although surely unrelated, I had also issues with coolant leaking (leading to overfill bottle emptiing and rad fan not kicking in), which I think I fixed (fingers crossed) by tightening all coolant hose clamps I could get to. Looks fine now. Any ideas? Link to comment Share on other sites More sharing options...
checksix Posted September 19, 2016 Share Posted September 19, 2016 Maybe just run some more fresh gas through it, mixed with a strong dose of seafoam. See if things improve after a few tanks. Link to comment Share on other sites More sharing options...
Member Contributer Aegisranger Posted September 20, 2016 Member Contributer Share Posted September 20, 2016 I like to run some Chevron Techron fuel additive now and then to keep the injectors clean, you could try that. Also, after my VFR sat for two years I found a mouse nest in the airbox on top of the air filter, so you should check that... Link to comment Share on other sites More sharing options...
checksix Posted September 20, 2016 Share Posted September 20, 2016 For sure check the air filter for critter nests. Some of the posts around here have amazing pictures of what mice can do. Link to comment Share on other sites More sharing options...
sudo Posted September 20, 2016 Share Posted September 20, 2016 Check your charging voltage too. Stators tend to go out around 50k miles. Link to comment Share on other sites More sharing options...
Nobody Posted September 21, 2016 Share Posted September 21, 2016 Another idea - spark plugs. Link to comment Share on other sites More sharing options...
CandyRedRC46 Posted September 21, 2016 Share Posted September 21, 2016 Stop playing around with the snake oil fuel additives, pull the injectors out send them away to be ultrasonic cleaned and rebuilt, then replace your fuel filter while you're waiting for them to come back. This would be a good time to replace your vacuum lines, spark plugs, clean the air filter and sync your starter valves. I used https://precisionautoinjectors.com/pages/about-us to service my injectors. $12 per injector and they came back with less than 1% variance. Also they rebuild them with new orings, filter screens and test for leaks/spray pattern/flow rate etc... Link to comment Share on other sites More sharing options...
Bruckner Posted September 21, 2016 Author Share Posted September 21, 2016 Lots of great input, thanks to all. I had been contemplating doing some servicing to the bike during the winter off season, including spark plugs. I will examine the service manual to see whether I can undertake this task myself, I'm wondering how to get to the rear cylinder bank! Doing this properly, I should also get to the rear bank valve cover and replace the gasket (or re-seal if there is none), it's been leaking a bit of oil there for years now. While in there, might as well adjust valves... a major undertaking at this point! In the meantime I will continue to ride the bike, check the stator voltage, and hope for an improvement, regardless of the work that it will require. Thanks and I will report back. Link to comment Share on other sites More sharing options...
CandyRedRC46 Posted September 21, 2016 Share Posted September 21, 2016 You are going to do a valve service before having the injectors serviced? Link to comment Share on other sites More sharing options...
Bruckner Posted September 22, 2016 Author Share Posted September 22, 2016 22 hours ago, CandyRedRC46 said: You are going to do a valve service before having the injectors serviced? I understand you are recommending otherwise, which surely makes sense but since the bike needs a valve cover gasket replaced, there is a case for the full job? But then, will I have the guts to go this far by myself?! That remains to be seen! I'm going through the second tank of fresh gas since I took the bike out of storage, let's see how it goes... Link to comment Share on other sites More sharing options...
CandyRedRC46 Posted September 22, 2016 Share Posted September 22, 2016 While I'm not going to give you shit for doing a valve service, more power to you, I would 100% pull the injectors out and have them serviced first. Nothing wrong with inspecting your valves every now and then, especially if you are already in there, but it has nothing to do with your rough running. Pull the injectors, it's an easy job. Sent from my Nexus 6 using Tapatalk Link to comment Share on other sites More sharing options...
Member Contributer Duc2V4 Posted September 22, 2016 Member Contributer Share Posted September 22, 2016 You can access the inner cylinder heads much easier when you remove the throttle bodies, which by sheer coincidence has the injectors on it... Link to comment Share on other sites More sharing options...
Bruckner Posted September 26, 2016 Author Share Posted September 26, 2016 On 22/09/2016 at 0:32 PM, Duc2V4 said: You can access the inner cylinder heads much easier when you remove the throttle bodies, which by sheer coincidence has the injectors on it... Yes that's the tricky part I imagine! It's a good winter project. Luck has it that I found a nail in my rear tire, yet another issue. In the meantime, a new piece of the puzzle, I noticed that the bike has none of the throttle issues I speak of when the bike is warm and has been stopped for a little while. In other words, I'll take the bike out for a few minutes, enough to warm it up to operating temperature, then switch off to buy groceries, and on the way back the engine delivers smooth power on acceleration for 2-3 minutes and then gets bad rapidly. Any new ideas? Another question: any point in disconnecting the battery to clear settings? Not sure the VFR has an ECU that self-adjusts the settings like most modern cars. Link to comment Share on other sites More sharing options...
Knight Posted September 26, 2016 Share Posted September 26, 2016 Did you have the tank up after removing the bike from storage? Did a hose such as a vent hose get crimped? That could generate vacuum only after the engine has run for a few minutes, and the vacuum can dissipate when the engine is off. When it is acting up, open the tank with another key. Does it produce a "whoosh", relieving the vacuum and temporarily fixing the problem? There is the possibility of a bad ground. The ground voltage builds up but has time to discharge when the bike is off, returning to zero volts. You'd have to inspect all input wires to the ground blocks for looseness/corrosion/burns to catch the offending circuit. Are the headlights on during the problem time as they should be? I am unsure if the surplus power of failed lights could cause immediate issues, but just a screwball thing that came to mind. (I am not sure of your country's configuration, ours headlights are on 100% of the time.) Link to comment Share on other sites More sharing options...
Member Contributer Aegisranger Posted September 27, 2016 Member Contributer Share Posted September 27, 2016 7 hours ago, Knight said: There is the possibility of a bad ground. Are the headlights on during the problem time as they should be? These electrical questions Knight asked made me think it could also be a bad battery. If it's shorting internally, it could cause your problem. Just a thought... Link to comment Share on other sites More sharing options...
CandyRedRC46 Posted September 27, 2016 Share Posted September 27, 2016 Installing a volt meter works wonders for staying on top of voltage issues... Link to comment Share on other sites More sharing options...
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