I bought a 2002 VFR recently, 25000 miles, very clean, all original. I work at a HONDA shop and originally sold it when it was new. Do to health reasons the original owner brought it to the shop for me to sell. Unfortunately the bike had sat in his garage for about a year without usage. He did ride it to the shop, however it was running poorly. I put fresh fuel in it and ran it for a couple of miles and it was not running on all four. Removed spark plugs, number three and four were fouled. I removed injectors and cleaned them. Number 3 injector needed replacing, also changed oil, had fuel in it do to stuck injector. The engine starts and idles great, and when it is cold before it heats up to operating temperature runs well, after it warms up it has a stumble from just off idle to about 2800 seems to clear out and again at around 4500 rpm, runs great above 5000. Any Ideas on troubleshooting would greatly be appreciated
Hey John you posted twice. See if you can edit your other post and delete it. Did the prior owner have periodic maintenance done? Did your shop service it and thus have the records? Was the recalled harness replaced? Is the air filter clean? Troubleshoot and adjust the wax idle unit which should be on only until the bike warms up. Clean and make sure of smooth movement, then tune the starter valves. This is the idle control circuit and affects idle, off-idle response, and partial throttle cruising. Measure the temperature of each exhaust (got laser?). That will tell you if all cylinders are now firing evenly. After running it hard, any vacuum when opening the tank? Make sure tank vent lines are run properly and not kinked. Does this generation have a carbon cannister? Test the battery voltage at idle and 5000 RPM. Inspect the stator to rectifier connector. Test the stator lead resistance and stator output voltages. Any modifications to this bike? Does it have a fuel controller like a Power Commander?
Be sure and carry oot the above to the letter. Knat is a one bike wonder with almost no practical experience or skill other than copying and pasting information from the other many sources of valid information. This dude pays his mechanic 90 bucks an hour probably to change oil.