The freakin saga continues

[Duke86max]

I ordered up the parts for the forks and am getting ready to go on vacation so I found a local Indy to do the front end while I'm gone. Went out to get on the bike to take it over to him. Hit the choke turned on the key bowls filled servo did it's thing hit the button spins but no start so I crank the throttle and it starts let off the throttle it quits. Crank it again and fires up and runs a little with throttle then quits. Crank again spins but doesn't start.

Bottom line is if I turn the key off then on and let the bowls fill up the bike will start with the throttle and run until the bowls empty and the tach and temp gauge don't work. The bike was running fine and it has been sitting about 1 1/2 weeks since I blew the fork seal. Only problem I did have was after riding for about 30 miles it would cut off then would crank back up. Any help would be appreciated.
Later
Duke

 

[RaWarrior]

You hear the clicking from under the seat when you turn the key on? It should click for a bit then slow and stop. Once you start the bike, put a finger on the fuel pump to "feel" for clicking since you can't really hear it over the motor.

If it clicks fast for a while then abruptly stops(a timer shuts it off after 2 or 3 seconds), there could be a leak somewhere and it's really not pumping much of anything. If you drain the bowls, you might have to cycle the key on/off twice until the fuel pump stops on it's own, since it can't totally refill them in the timer's span. There's a thread here somewhere about if your fuel pump clicks constantly.

 

[davidon]

Clean pilot jets and or try shotgun/peashooter first ..gas is getting crappier...I had a similar problem with gas sitting for a week or so..also add some Seafoam to gas

 

[dmax1]

Possibly the valve in the fuel pump has become dislodged. If pump run fast after a few key cycles this could be your problem.

 

[VMAX1260]

when you fire it up with the throttle if you leave the throttle but you have your choke on what does it do ?

 

[Mad-V-Maxr]

Sounds kinda like the problem I was havin a few weeks ago pump shut off and no tach or temp readings. Mine turned out to be the signal wire connection at fuse block under fake tank cover. I was really frustrated took me two weeks to figure it out.

 

[mattness]

ya it sounds electrical cuz the gauges arent working

 

[Duke86max]

when you fire it up with the throttle if you leave the throttle but you have your choke on what does it do ?

It cuts off won't run with the choke.

I just got home so I haven't had time to mess with it hopefully in the morning. I am thinking electrical as well.
Later
Duke

 

[4gasem]

Do you run ethanol in it?

 

[Duke86max]

I don't run Ethanol per say but our pumps here in NC read " May contain up to 10% ethanol"

 

[Duke86max]

Worked on the bike a bit this morning. Drained the bowls on the right side got to the left side and got nothing when I turned the screws. Took and backfed with air pressure and got fuel out the hoses. Temp. gauge is working tach is just barely bouncing off the needle.

Everytime I turn the key off then on fuel pump works for about 4 seconds but when I run it and it shuts off the fuel pump doesn't come back on. I pulled the wire on the fuel pump and checked with meter when I turn the key on I have about 11.5 for 4 seconds then the relay clicks and no voltage. Start the bike and no voltage so now I'm wondering relay or is something else not telling the relay to kick back on after it is started. What would keep the relay from coming on after the motor starts? Is there a way to bypass the relay to get the fuel pump to run all of the time to check it?
Later
Duke

 

[Thevmaxrider]

You definitely have an electrical issue not a fuel one. If you don't have a copy of the maintenance manual with the electrical schematics troubleshooting can be problematic. My supposition is that because your tach isn't showing the proper RPM there may be an issue where a cutoff that would normally allow power to the fuel pump when the engine is running thinks the engine is off and therefore won't turn the pump on. Not 100% up on that portion of the Vmax electrical, but it makes sense that they would have something to this effect. Check the connections to the relays under the left scoop first and go from there.

 

[Duke86max]

That's kinda where I'm at as well. I do have a schematic and there is a brown wire at the fuel pump relay that goes to the tach so that's where I think I'm on the right track just not sure exactly what I'm looking for. I'm kinda challenged when it comes to electronics and electrical stuff.
Thanks
Duke

 

[Duke86max]

Worked a little more and this is what I tested.
The fuel sending unit ohms out at .89 book says .9 + or - 0.2
The red and white wire in fuel pump relay is hot with switch on red and white and red and green wires are hot when in res. position. The thing I don't understand about that is the bike has never run with the switch in the on position only res.

Also after I pulled the relay panel I saw that the cable to the Vboost is disconnected. The servo is working so I'm not sure why it's unhooked but the whole thing is just hanging there.

All I can think of for now
Duke

 

[naughtyG]

When you say the cable to the vboost, do you mean the vboost controller? (big square box under left scoop). Got a pic of what you're talking about?
Once reconnected, with engine on and warmed up, if you rev up to 6k rpm you should see the vboost valves opening. If not there's a problem.

About your ON/RES switch, have you taken the switch off the handlebars to check its function and clean its contacts? Also, while it's off you could check the cables going from the switch to the relay for continuity.

I would also get another fuel pump relay (Sean Morley?) to try and swap it to see if that's your problem.

 

[ColoNat]

i think he means the actuating cable from the controller to the valves was disconnected. funny, found the same thing on mine when i pulled carbs to rebuild them. wonder if it's something that can get knocked off by accident?

Sean, have you seen this as an issue?

 

[Duke86max]

Yes it's the cable going to the servo I found a video on youtube that shows the servo working and it looks like there is a brass barrel that is above where the barrel for the cable goes that has some kind of pin going through it to hold the barrel in the servo.

As for the switch I have not taken it off of the handlebar I have been trying to track down the ground wires and check to see if something is loose but have only found the one that is under the right cover hooked to the antifreeze fill spout. If anyone can save me some tracing and tell me where to look for more I would appreciate it.

I tried to check continuity on the relay plug but the alligator clip I have on the end of my test light won't go down into the small hole.

I "think" the relay is o.k. as it cycles the fuel pump everytime I turn the key on then clicks and shuts it off after 5 seconds as specified. Can the relay partially work or when it goes it is completely gone?

I talked with a guy at work who knows electronics and he stated that with the problem I was having with the tach going crazy then the bike cutting off it sounded to him like a switch or relay getting hot and finally just went out or a corroded ground wire since the bike was fine and now not getting any voltage to the fuel pump when running after sitting for a week and a half. But this makes no sense to me as the pump gets power for 5 second when I turn the key on.

I'm just lost with this electronics stuff some of the trouble shooting steps show the ohm meter set to 1x and my meter only has 20, 200, 2000 etc.

Thanks for the help guys
Duke

 

[Duke86max]

Here's a pic of the cable not great but hopefully you can see what I'm talking about.

Later
Duke

 

[Duke86max]

On the plug tha goes to the fuel pump relay there is a red/white wire and a red/green wire they come from the on/res. switch. I checked these with the switch on and have constant 12v. I checked with a test light between the 2 wires and got nothing (continuity?) I checked it with a meter set to 20k ohm and got -0.36.

Any thoughts? I'm thinking if I have 12v to the relay but not to the pump it must be the relay keeping it from getting there.
Duke

After looking into this farther I realize the red/white wire to the rleay is for the coil nothing to do with the switch. Only the red/green wire comes from the switch.

 

[naughtyG]

I still think your best bet is to inspect / clean every electrical connector and switch you can get to.

Get some electronics cleaning spray (isopropyl alcohol) and some dielectric grease, and I bet this will fix your problems.