I have a new to me 2001 VFR 800i with ~ 31,000 miles. It is surging slightly below 4500 rpm. By surging I mean that the power will surge without changing the throttle setting. From reading on this forum I found how to pull the F1 codes. When I jumped the service check connector and turned the ignition key too on with the side stand down the F1 light blinked one short blink then a 3 second pause and a short blink. This continued until I turned the ignition off. Am I correct in reading this (The F1 code) as a code 1 MAP sensor issue? 2nd I’ve noticed while riding a high pitched whine that starts at around 4100 rpm and builds up to around 4300 rpm and then fades until around 4500 rpm, then it’s gone. At it’s loudest it’s fairly loud. Is this normal? Any idea what it is? Thanks in advance for you help.
Welcome to the forum. Congrats on the bike. Sucks that you have an FI code already. Yes, 1 short blink does equal the map sensor. It seems strange, but there has been a "flurry" of people reporting their map sensors have gone bad recently. I was one of them. But its a strange thing to have a MAP sensor fail (and they are disgustingly expensive to replace). Check out the sensor, clean it up, reconnect, and clear your FI code and see if it goes away. If not, my next suggestion would be to check the wiring for your R/R (regulator rectifier). There's a "bazillion" threads on here about bad R/R. My own recent personal experience with my (supposedly) bad MAP sensor turned out to be a bunch of crispy wires with my R/R and Stator. These bikes, if you aren't aware, are notorious for shitty electrical systems. Your R/R WILL need replacing if it hasn't been done already. As for the high pitched whine: These bikes have gear driven cams. Its a unique sound that would definitely be described as a whine. Typically I would say the sound is always there, but your saying you only hear it at a certain range. Is it maybe an issue that its always there but most noticeable at the RPMs you describe? You can also go on Google and see if you can find some VFR with video and/or soundclips. Do they sound like yours, or way different? Good luck and get back to us. We'll help you through this!
As to the R/R, I don’t know how much good it did but the previous owner said that the rectifier had been replaced by a factory recall. Any word on if the recall actually fixed the issue? Thanks again.
Not sure. My bike is a 2000, so its identical to your 2001. I am/was not aware of any recall issued on the R/R. To the contrary, it seems its one of these things that Honda knew they screwed up on, but failed to correct. They used inadequate wiring; the R/R was placed in a poor spot where it didn't allow it to cool properly, and it resulted in various electrical problems. Over and over and over again. I don't think there was a recall - maybe the seller was giving you a bill of goods? Even if it was replaced some time ago, its "old" technology. The new ones use MOSFET technology. Check out this link below: Wire My Bike Don't get me wrong, I'm not saying 100% its your R/R. But a bad R/R can lead to a host of problems, as I found out. Speed sensors, MAP sensors, BARO sensors... all because of the R/R. Besides, its good to check your R/R and simple to do if you have a voltmeter. If not, get one. $10 to $20 will work just fine. Voltage with a fully charged battery should be 12.8 to 13.2 with the bike off. At idle once warmed up, should be in the 13.x Volt range. Increase your RPMs up to 5000. At 5K, it should be mid 14V, give or take a few tenths. If you're not at these numbers, you have an issue. If you're number fluctuate wildly, you have an issue. If everything checks out and the volts are good, then maybe you need that MAP sensor!
I have a volt meter but I don’t have the repair manual yet. Where do I measure the Voltage, from the R/R out? If so where is the R/R? Thanks again for all the info.
I found a good write up on the R/R issue here: VFR Regulator/Rectifier Failure And a good guide to electrical fault finding here: https://www.electrosport.com/technical-resources/diagnosis-center/fault-finding-guide When it stops raining here I’ll do the checks and post the info.
Not bad reads, but R/R can got at any point. I bought my bike with 5200 miles on it. The R/R had already been replace at that time (it was from a Blackbird). Had the cooling fins, was larger, whatever. But it still failed within 10,000 miles. One of the key things is to solder the wires, especially from the R/R to the stator. If not, you might only be prolonging the inevitable. The exception to this would be if you installed the VFRness. That part is described on the website I posted above for WireMyBike. With the VFRness, it eliminates the need to solder the wires. (Although I did it anyway). Checking the voltage output - at least to get all this started - is done at the battery. Its doesn't get much easier then removing your seat and hooking the voltmeter up to battery! Once you move along, you can check the Volts at the R/R, or check the ohms on the stator.
I’ve run the checks. First the battery is sitting at 10v with the bike off. How much can the low battery affect the results? With the bike at idle it is at 12v. With the bike at 5K it is still at 12v. I noticed that the R/R has cooling fins and had read that the originals did not. I looked up the part # and it is a OEM Honda Regulator that was put out for 02 and 03 bikes, so it looks like the bike has killed it’s 2nd R/R. I’ll be ordering the new R/R and VFRness from wire my bike this weekend. I’ll recheck the #s after I have the new one in and post the results. Thanks again for all the help.
How can it run so low? It has a huge effect. If the voltage is low the FI computer gets false readings from the sensors, hence the surging. You can try to charge the battery, but it is likely toast. Should be about 12.8 with the bike off. Get a new battery if it won't hold a charge. The R/R is working it's guts out trying to charge a dead battery. They are not designed to survive that level of extreme loading for very long...
It is possible that its your battery, as KennyBobby just said. Your readings are definitely way low, and even if it was/is the battery, your R/R could be on its way out due to working "overtime". Just because it had fins (which certainly helped) doesn't make it bulletproof. I think I mentioned my bike had a R/R from a Blackbird: plenty of fins. Still didn't last all of 10,000 miles. I think you'll be really happy once you get the new R/R and VFRness on there, but keep in mind its possible your battery is toast now too. Once you get all this fixed though, you can sit back, relax, and enjoy racking up the miles!
So a quick update. I got a new battery and the R/R and VFRness installed. The charging system is now putting out good #s, 12.8v with the bike off, 13.5V at idle and 14.5V at 5000 RPM. I’ve also had the valves checked, the bike has ~31,000 miles and they had never been checked. All good upgrades and maintenance that needed to be done. I am still having the surging issue and the F1 1 blink MAP sensor code. I disconnected the sensor, cleaned the connection, applied diastolic grease and reconnected the sensor but still got the F1 code with the engine running and the side stand down. I read somewhere that you can test the MAP sensor by running the bike with it disconnected, that this causes the ECU to fall back to preset data for the MAP sensor. I disconnected the sensor and am running the bike with it disconnected. I’ve but a little over 100 miles on so far and it seams to be running better. I plan on keeping it disconnected for a week or two and see how it does.
Glad to see that things are improving. Even though the new R/R and VFRness weren't the cause of the code or the surging, you still do a good thing by changing them. That was money well spent to avoid breakdowns on the side of the road. I'm personally not familiar with running it unplugged to try and reset, but let us know how that works out. If you do end up needing a new MAP sensor, let me know. I did a fair amount of research (those things are fucking expensive!!) and I think I saved a bunch of the links. Flea Bay may be the best bet; pick one up for $30 or so and cross your fingers that it works.
