VFR 800 Fuel Pump Problem - Help!

Yesterday I stripped off the bodywork off an 2000 VFR 800, including dash and lights. Today, I put the body work back on and hooked everything back up - all seemingly correct. However, the fuel pump does not work? I tested the pump by hotwires, and it does not work. There is no voltage across the 2 pins on the fuel pump connector? No damage to wores or connector noted. I don't know where the fuel pump relay -if any- is located. I checked fuse and even replaced it and it's OK. Strange, but I could not detect voltage across the fuel pump fuse terminals with the key on? Over the top of the Fign/pump fuse there sits a 3 pronged spade/fuse sideways - its function is not identified? I checked all the issues like kill switch, side stand, clutch lever and gear selection in neutral. Nothing seems to solve the problem, and I'm clueless. I do not have access to a shop manual or wiring diagram, which obvioulsy would help a lot. Any help appreciated. Thanks

 

Been through all of this just two days ago.
Fuel pump cutoff relay is located just aft of rear brake resovoir.
Fuel pump circuit will only show a voltage for about two seconds once the key is turned on, so you may be missing it.
P.M. me if more info needed as we seem to be on the same trail.

 

Cpt John: Thanks for the info. I solved problem last night. I mounted the lean angle sensor upside down. How stupid of me.

 

Not really, What is stupid IMHO is that Honda have wired this bank angle sensor so that when open circuit bike will not start. If you get a failure in this circuit it would be a hell of a job to find it roadside. As all this device does is to shut the engine off in event of a get off, it should be wired so that if it or the wiring fails the bike does not stop. That said I have not heard of any instances of the angle sensor giving trouble.

 

Since fuel injection pumps operate at a very high pressure I believe that it would be wise to provide this safety cutoff in the event of a cockup. Imagine petrol at 40-60 psi being atomized over the bike from a cracked line or fitting.
Thanks for the info. I've just joined the brotherhood of the vfr.

Scott
2000 vfr
san francisco

 

Hi all!

First things first, better late than never.... Happy New Years to all!

I have a 2000 Honda VFR 800 (jap spec). Bike has a bit of a history. The Jap spec VFR's are restricted to speeds I hear, as even the speedo shows only upto a 180kmph. The previous owner of the bike had it derestricted (not sure what had been done but it did the job without any issues I'd like to believe) and the bike was working perfectly fine right until I had given it for general service. The bike now has a few problems which I am not able diagnose let alone fix.

1) When ignition and kill switch are turned on, the fuel pump is supposed to come on, load the rails and cut off until the engine is fired up again. Right now, the problem I face is, the fuel pump does not cut off at all.

2) And once the bike is fired up, as it gets warmer, the idle goes upto almost 3000 rpm. Blip the throttle once and it settles down to 1500 for idle briefly, and slowly creeps up to 3000 again. And the power delivery below 3500 rpm is very rough and glitchy (bogs down and spikes randomly).

3) The bike smells like its running really rich on idle from the pipes (stock pipes). And as you move, below the 3500 rpm glitchy region, you can feel it from going rich to even lean sometimes from the induction noise. This could explain the random power delivery in that rpm band.

4) The clutch is one other thing I'm facing troubles with. Rolling off on idle is not a problem. But if you have anything even close to 2500 rpm or above for settling off, even if your really really careful with the clutch. Out of nowhere there comes a sudden pop off clutch.

I'm not too sure of what all has been done to the bike before I picked it up. But it was working fine despite derestriction. Post service, I am facing the above mentioned issues. And when I had to swap out the battery, I noticed a small shorting wire in one of the connectors in the wiring harness. I am not sure for what reason that shorting was done (maybe the derestriction itself?). But the malfunction light isn't indicating any malfunctions as such. I know the lights do work as they all light up on ignition on for systems check. But turn off once the engine is fired up.

I am hoping to bring my bike back to its original glory again without any glitches.

Thanks again!

Cheers!
Surya

 

Surya, welcome to the forum it is good to have you here! I hope you introduce yourself in the introduction forum and provide pictures of your bike.

Please explain, "I noticed a small shorting wire in one of the connectors in the wiring harness". Is this a wire that is shorting two pins in a connector? Where is the connector and what does it look like? Is it connected to something or open?

What service did they do exactly?

The fuel pump always running sounds like a short or melted fuse.

Regarding the clutch problem: Did they do an oil change? Starting from very simple things that could be wrong, using the wrong oil, an automotive oil with friction modifiers, will slip the clutch. If true, the oil should be changed immediately, do not do a lot of riding. Honda's motorcycle 10w40 works very well. Some people spend the money on various premium synthetic oils.

Hopefully someone here knows of the speed restriction and can guide you on finding that short. Hopefully your forthcoming description of the type of maintenance will help indicate where the problem is.

 

Hey Surya, welcome aboard!

I'll answer in order:

1. Sounds like a faulty fuel pump. When the pump achieves a certain pressure, it should automatically shut off. Usually the pressure switch is built into the pump.

2. Could be related to the fuel pressure and the pump not stopping or could be a vacuum leak. Lots of other possibilities here as well. I would start with solving the fuel delivery first, then work through each problem one at a time as some could be related.

3. Again, could be related to the fuel pump and the computer trying to compensate.

4. Check the fluids and lines. Bleed the clutch. Check to make sure the push rod on the slave cylinder isn't gummed up. If those don't help, then you will need to check your clutch plates and springs. Also, as Knight noted - the wrong motor oil could cause issues as well. Use oils designed for motorcycles.

 

Good Day folks!

Thanks for the replies! Much appreciated.

About the short wire to the connector, yes two pins have been shorted in a connector with a piece of wire that is under the seat. And the service was a general fluid change and regular maintenance, pads and filters. But I did notice one thing regarding the fuel pump issue. I had gone to another garage and he tried an ECU from another VFR. We plugged that in just to check and the fuel pump cut off on ignition worked perfectly fine. Fire up the engine and everything runs smooth. Now I have kind of figured how to solve this fuel system related issues and the running rich/lean problems. I think the previous garage swapped my ECU and I'm going to have a word with him on that but I also have a feeling it is going to be absolutely redundant knowing how he responds to these scenarios. I reckon all I might have to do now is change the ECU. Any thoughts?

Things aren't gonna be that easy though. The problem I now face is, ECU match. I hear there are different versions of wiring harnesses? And thus there are variations in the types of ECU's too, designed to match only to those specified harnesses. I know I have a wiring harness and an ECU that do not match. I have a second ECU which works but there is no print/sticker to give me the number or model. So now I'm left blind to know there is a good ECU out there somewhere which I need to buy but don't know how to identify which one it has to be.

Is there any way I can find out the serial number or type of my wiring harness so I may then start hunting for the matched ECU?

And the clutch. I shall try rebleeding the system and checking the slave cylinder. I am to get a new set of clutch plates and springs soon and also get the correct oil.

I have another small query. My front right fork oil seals are out. Any spare for the VFR, I'm going to have to import it to India as we don't have anymore than lets say 50 of these bikes in the entire country (that number is being super optimistic by the way). Oil seals are not a big deal but the process of importing them here is not gonna be easy. Is there any other bike's oil seal that might work? Bikes like R1, CBR1000, Benelli 600, are all available here. Would any of those fit the VFR's forks?

Thanks folks. You have no idea how much help this is, finally talking to people who know about the bike is such a rewarding feeling at the moment.

Cheers,
Surya

 

I have a 1997 VTR1000F that was made for the Japanese market and had a 180km/hr speedo and was restricted to that. The restrictor was purely electrical and controlled by the speedo, functioned just the same as the rev limiter. To derestrict I just disconnected a single green/pink wire from the back of the speedo.

Fork seals are pretty interchangeable and the same 41mm seal is used in many other Hondas.

Sent from my iPhone using Tapatalk

 

Thanks for that mate. That's one big thing knocked off the list now, I now know derestricting it shouldn't affect the bike's ECU calibration. Perfect. I will have to check if Honda here have spares for the big size forks, one that will fit the older forks. As most big Honda's here are fireblades and they come with inverted forks unlike the VFR, I'm going to have to check compatibility of the Oil Seal's seats. But much help again.

Thanks mate!

Cheers,
Surya

 

Surya here's a link to Partzilla showing the other Honda's that use the same seal as the VFR.

http://www.partzilla.com/parts/detail/honda/HP-51490-MN8-305.html

 

Sweet!

Thanks a bunch mate. I'm going to have to order it and import it. None of the bikes on that list are here in India, at least not through Honda themselves as dealership sales. Only Honda's sold here are the new fireblades and the 600's and the CBR250R. Thanks again.

Cheers,
Surya

 

Surya: regarding your clutch problem, that's common for a stock VFR.
There are a few threads about it on here, and the fix is to install stiffer clutch springs (since the problem is caused by springs too soft for such large friction plates). I went with the standard Barnett ones and now I can launch at a decent RPM range without the clutch freaking out on me.

 

Perfect. Thanks for the info mate. Now it all makes sense (weaker springs).

I have heard one more thing about assembling the plates (not sure how legit this is but it does seem fair). In the case of the steel plates (which are metal sheets stamped out), you have to feel the outer edges of the plates. One edge on the circumference would be sharper than the other. When assembling, the sharper edge apparently should face outwards, away from the clutch basket. I am not sure how it has been done on my bike, will check it out when I open my bike for all these faults mentioned above. But does this have a big effect generally on the clutch plates?

 

I don't think it actually makes a difference which way the spacers face. But I've heard this as well.