87 VFR 700 - no power, no idle. Strange wires.

If this post in the wrong place, I apologize and I will move it.

As I'm sure with many first posts here - My bike is broken. I just got the clymer 20 minutes ago, but I thought I'd check with you guys as well.


This is how I bought the bike -

Starting -

Needs FULL choke to start, and won't start unless you're on the throttle a bit as well. The bike only has the strength to stay running above 2000 rpms. If it dips below, it starts to sputter and shuts down fairly quick. If you set the idle to about 2100 rpm, it stays running for a while.

Riding -

No matter how far you drive it, it still won't idle. I actually rode the bike home about 50 miles. The bike responds noticeably better between 2krpm and 4500 rpm, but she's still a pig. Anywhere outside of this rev range, it immediately loses power. If I didn't have this little bit of power here, you couldn't take the bike on the road. It will not exceed 55mph on level ground. You need 3rd gear for inclines. It'll do about 75 downhill.


... the condition -

Someone who knew nothing about motorcycles bought this after it had sat for two years. They claim to have changed the voltage regulator and a fuel pump to get it in the condition I have now. The fuel pump clicks like CRAZY almost all of the time. It will slow down, but it sounds obnoxious.

There is a female red connector with grey/black and a green/black wires with nothing plugged in to the other end. This is under the seat, close to the battery. The part of the harness that goes in the direction of the fuel pump has three plugs underneath a clear rubber weather cover. Of the three connectors - one goes to the fuel pump. One goes nowhere and has 3 wires. It has a blue/red wire cut off, and has a blue/black and a black wire actually spliced together at the end. The third one seems to go to the voltage regulator, but there is some hackery there as well.


I know that my 26 year old bike very well and almost surely needs a carb cleaning, and it what I describe could be the carbs.

I really feel like this guy bought a generic regulator, a generic fuel pump, and tried to hack it together.

 

Hmm

First things first - Welcome to the MadHouse! :welcome:

When you get time make sure you head over to the "introductions" part of the forum and say Hi to the rest of forum, tell us a bit about your biking history and your VFR making sure to add at least one decent photo of the bike or you will face merciless raggin until you do! Also its a good idea to update your forum profile "My Profile" link at the very top of the page to include the specs of your bike and a rough location city/state so they appear with all your posts automatically and if you are looking for help you may find someone nearby willing to swing by and offer advice especially if you have a well stocked beer fridge.

:focus:

The old saying remains true - a picture is worth a thousand words and doubly so on this forum where people really like to see photos so we can work out what it is you are talking about. So head out to that bike and take a heap of pictures of the bike, then with the seat removed showing the various wires you see have been hacked along with the generic RR and fuel pump. Off load the pictures onto your computer and sort through them to find the ones which best show the problem areas. Then post them up on here - its easy - just click "reply" then click on the "Insert Image" icon and follow the prompts to locate, select and upload the pictures here along with any additional commentary. NB Depending on your connection speed the "Insert Image" function can be a bit slow, so just follow the prompts.

Whilst I doubt I will be able to answer any of your specific questions I think once we get to see pictures of the various suspects, there are folks on here who will be able to answer your questions far better than I can.

Good luck and get busy with the camera.



SkiMad

 

First of all - thx for the warm welcome. Some forums can be a nightmare to start out on. I will follow through on your other suggestions, in the mean time - here is said Hackery.

In the red circle, you have the blu/blk and blk wires spiliced together. In the green circle, I have my mystery plug. I am going through the point to point now to try to figure out what this connector is.



The zip tied affair is not my work. I'm trying to save this bike by not doing this type of crap to it.

 

Welcome!

I think the red connector in the green circle is for the low fuel level sensor. If it's still in there, you may see the other end dangling under the tank. You may have to lift the tank to find it.

Tim

 

Lifted the tank, and I've got cut electrical wires coming from the rear bottom end of the fuel compartment in the tank - towards the bottom rear end of the overall structure, behind some type of insulator material. I'm guessing these are the wires to the fuel sensor that were cut. I'll find out for sure tom with some daylight, but Im 90% sure given what you have said.

Man, this bike is hacked to pieces that could be waiting to kill someone. Not with anything I've see, but if this type of shoddy work had been done to the structure or suspension.... geesh. I'm glad I bought it and I'm seeing all of this stuff. Tomorrow I will look deeper in to this, but im going to bet you're right on the fuel sensor redbeast. Thanks for that.

 

If it's that bad, I'd be looking at everything else with a keen eye before taking it for another ride....brakes, wheel bearings, tires, chain and sprockets, etc etc...sounds like the carbs will be coming off. Bit by bit, you'll get there!

Have fun,

Tim

 

Told you it won't take long to round up some answers once you post up pictures!

The fins protruding behind the frame look suspiciously like a 6th Gen RR has been mounted where the original RR would go. They have the advantage of larger cooling fins for better heat dissipation - so don't be too hasty to write off that mod as they should be more reliable than the original if it has been wired up correctly. But its under seat location puts it mostly out of the air flow which is not ideal. That's why on later models the RR got moved upfront as the RR can get pretty hot and really needs every little help to dissipate excess heat.

Sadly the charging system has been the achillies heel of most VFRs and the following thread gives a pretty good insight to the issues and solutions just in case it also applies to your bike -

http://vfrworld.com/forums/showthre...ator-Stator-failures?highlight=rubo+stator+rr

On bikes that old, it seems that undersized wiring in the loom, melted connectors and corroded earthing points were problematic, so it is probably well worth checking the RR/Stator connections for signs of melting. With luck that RR upgrade rather suggests the previous owner may have already been there and fixed it for you.:biggrin:

Take care



SkiMad

 

Thx for the info and link. Looking at what few photos I have I did catch that RR change. Nice to get an idea of where its from.

I got it to idle at about 1200, but very poorly. I haven't ridden, but Im almost positive the power issue is still there. Basically at 1200 it goes ok for a bit, starts to die, jumps up in RPM like it has a vac leak, then comes back down to 1k rpm and repeats. If it dips below about 750 in rpm it will die no matter what.

 

thinking of seafoaming the carbs... I have a lot of experience with seafoam, and in some cases I flat out wouldnt use it in some cars. I'm thinking of letting sit in the carbs overnight. I know thats a cheat way to lazily and half-arsedly clean the carbs.

 

Doesn't anyone else know anything about the wires that are cut in my harness? What is the Blue wire with the Red stripe?

 

Wait a second: wires on gens 1-3 are thick and robust, while subsequent gens had the much thinner wires.

 

You are right! I am glad someone was paying attention. Note to self I must step back from the keyboard once the McCallan is open - purely medicinal of course with all this dratted snow we are getting - its really frustrating not being able to get out on the VFR! Does make you wonder what on earth happened to that bikes electrics that inspired all the butchery to the wiring?

SkiMad

 

Hey X, what color are the wires? Earlier you posted "In the red circle, you have the blu/blk and blk wires spiliced together." Now it's blue/red??? I'm changing the rear shock on mine right now(arhg!) and I see wires coming out of the same harness that I THINK goes to the fuel cut off relay...that relay also has a yellow/green wire with a bullet connector...I can take a pic if you want...check the wiring diagram in the manual(DL if you don't have the book). I've attached quick shot of the manual for ya....


Good luck,

Tim

 

Tim

In the red circle I have three wires

1 - Black
2 - Blue/Black
3 - Blue/White

1 is spliced in to 2, and 3 is just cut - going nowhere

 

Seafoam is in the tank. and has been sprayed through the throttle bodies. I let it run for a bit to let the gas with the cleaner get in to the bowls, etc.

While I was doing this - the bike was running very erratic

... but it had IMMENSELY more power. It has NEVER run like this. It feels like I was revving a riding lawn mower before compared to what it's doing now.



I am trying not to get too excited. I fear maybe the seafoam is acting like starting fluid or something, and back on pump gas it will turn back in to a John Deere

 

Fuel filter is DISGUSTING. Should probably look into why it's so dirty before you get too crazy with trying to get the carbs cleaned out, Seafoam-style or otherwise. It's a diaphragm style, so the pump is clicking constantly because it isn't getting enough fuel. Is the pump connected to a relay? Or did they just hook it directly to 12v? Not necessarily bad if it's hooked straight to power (people have done it to eliminate the relay.)

 

Just saw that post. That sounds like your relay has been eliminated and they just jumped power on the harness to run a constant 12v to the pump. That pump is definitely an eBay special, by the way.

 

"That pump is definitely an eBay special, by the way."


great :unsure:

and yeah, we are changing the fuel filter tonight. thanks for confirming that. There is actually sediment in the bottom of it.

Is it odd that my fuel filter is now only half full of fuel? I could see a little air bubble in it to begin with.

Definitely going to check the fuel system for a blockage somewhere

 

It's normal for the filter to have some air at the top.

 

Those big plastic filters will do that. Look like a Wix. I experimented with several recently on my bike (same model) and they are crap. Each one I put on got too hot and softened after a few days of riding. The outlets would be bent down at about 45 degrees from heating up and flexing and the adhesive they use to attach the paper element would all be gathered at the bottom impeding flow. Use a good metal filter with a screen element. It will fill up all the way and stay that way. The micron filtration rating is less though, so make sure you get that presumably filthy tank cleaned out and treated and change your fuel lines to be safe. Squirrelman and I actually discussed the "half-full filter" thing recently, and I forgot to share my findings. Hopefully he sees them here.