No Spark When Wet?!?

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95spfldmax and max power, have you guys searched the forums for any other mention of this problem? I did, but I sure could have missed something. It seems weird that three of us (or more) are having this problem and it seems to be a new issue. At this point I'm open to ANY suggestions....


I searched, but didnt find much other than this thread. I'll try checking the output of the switch if I can get to it. wasn't in the mood for disassembling the bike, but when am I ever.
 
Since the bike has decided to run again, I figured I would test the diode again. It still shows no continuity between the 3 sets of wires, regardless of how I check them. My multimeter has a diode test feature, so I figured what the heck? I tested the three pairs of wires and found the diodes ALL test okay that way. They all gave about .54 volts, and since they are silicone diodes, they should be between .3 and .7 volts. Any ideas guys? Can't trust it - ready to sell it unless I can find a REAL solution.
 
Okay, here's the weirdest thing yet...It still starts without the diode in it!!:ummm:
What the hell is going on with this thing?!? I tried to start it in gear, and it won't. I pull the clutch in with it in gear and it started right up. Keep in mind, this is with the diode unhooked and sitting on my bench. Any ideas guys?:bang head:
 
vmaxinID,
Yep, it starts right up when it's dry. It seems to take longer to dry out some times. Any idea why it would start and run like a top with the diode sitting on the work bench? Maybe I should just tape of the diode connection and call it good!
 
My only guess is a cracked coil(s) letting in moisture?

Then when it dries it starts?

That plays into my theory of my hot idle/surge problem that when the coil(s) get hot it/they short through a crack in their housing. I replaced my back two '95/28,000mi coils with my back two '86/65,000mi (not exactly fresh) but no improvement. Been too lazy to swap out the fronts because they're so buried. Maybe I should buy 4 "fresher" ones and see if both problems go away?? :bang head:

Especially before I spring for a "younger" set of pick-up coils which is still high on my suspect list.......
 
Here's a couple of very simple things to try

Try turning off the lights in your garage and closing the doors to get a real dark environment (don't stay in there too long with the bike running : ) If you don't have a garage find a dark place. Start or try to start it and keep an eye out for arcing in the wires coils etc. or any where you might suspect there's a problem. Wiggle wires around on the harness. Had a cracked plug porcelain on a new plug once that drove me nuts and finally caught it this way.

Next the VMAX connectors corrode over time especially when you live in a wet environment. Take a piece of fine emory paper like a 320 grit. Fold it up small and go through all of your electrical connectors cleaning the pins or spade connections. Make them shinny again. Your lights will brighten up and you may be surprised to find your problem goes away.

Last get some dielectric grease and put some on the plug wire boots and connections. It will keep the water out in the future. You can find it at a boat store or radio shack. There's also some sprays that are good for dispersing water. I suspect you have a short somewhere and the water makes it worst, hope you can find it with the lights out deal.

Good Luck and it helps to drink beer while doing the connector cleaning.
 
Fellas, my bike is an 06 with < 8,000mi. All of my coils cant be bad one day, then all be good the next. Its gotta be something in front of them, just cant figure out what.

I'll try the above dark trick tonight and report back.
 
Here's a couple of very simple things to try

Try turning off the lights in your garage and closing the doors to get a real dark environment (don't stay in there too long with the bike running : ) If you don't have a garage find a dark place. Start or try to start it and keep an eye out for arcing in the wires coils etc. or any where you might suspect there's a problem. Wiggle wires around on the harness. Had a cracked plug porcelain on a new plug once that drove me nuts and finally caught it this way.

Next the VMAX connectors corrode over time especially when you live in a wet environment. Take a piece of fine emory paper like a 320 grit. Fold it up small and go through all of your electrical connectors cleaning the pins or spade connections. Make them shinny again. Your lights will brighten up and you may be surprised to find your problem goes away.

Last get some dielectric grease and put some on the plug wire boots and connections. It will keep the water out in the future. You can find it at a boat store or radio shack. There's also some sprays that are good for dispersing water. I suspect you have a short somewhere and the water makes it worst, hope you can find it with the lights out deal.

Good Luck and it helps to drink beer while doing the connector cleaning.

These are all good sugestions and amazingly I already thought of them. No arching to see or "hear".....and did all my connections recently to solve my charging problem I had a while back..........
 
Great idea, I'll see what I can see in the dark tonight. It still doesn't make any sense the sucker would run WITHOUT the diode, does it?
 
Great idea, I'll see what I can see in the dark tonight. It still doesn't make any sense the sucker would run WITHOUT the diode, does it?

Diodes are normally used to supress electrical noise or as an elecrical check valve that allows current in one direction and not the other. That's a very simple explination as they can be used for other things. Sooo it does make some sense that it will run without... maybe not as well.
 
TURBOVMAX, thanks for the info! I was under the impression that the diode was part of the control mechanism for the kick stand/clutch safety switches. I'm going to soak the one I'm replacing in water for an hour, then plug it back in and see if it starts.
 
Guys, I think I might have found it! When I first pulled the diode out of the bike, I noticed that the rubber boot around the diode was loose. My buddy pulled the rubber boot off, but it was only stuck on in a couple places. While I was soaking it in water I noticed that there were three exposed contacts on the side of the diode. I tested the three contacts and found that the two circled contacts are showing .54 volts between them. With the condition of the outer cover, and the way it sits in the bike, when it rains the water would go right into the diode and enter between the cover and the diode. When I shorted the two corresponding wires, it would crank, but not start!!:biglaugh: It seems to me that as long as the diode is sealed up well and water can't get into the boot and sit there, I should be back on the road. If you are having this problem, you might want to start by checking the condition of the rubber boot on the diode.:punk:
 

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Okay, here's what I did:
The first picture shows the diode with the rubber cover off. I used brush-on electrical tape to cover the exposed contacts. In the second picture, once the brush-on tape was dry, I put the rubber cover back on and sealed the top with clear adhesive. Now it's dry, and there's almost no chance for water to get into it again. Even if it does, the contacts are all covered, so it shouldn't make any difference. I'll keep you posted on how it turns out.

By the way, if you want to try shorting the connections on the motorcycle side of the connector, MAKE SURE IT'S IN NEUTRAL AND/OR ON THE CENTER STAND!! If you short the white wire to the sky blue or white with green watch out. When you turn the key on, the motor will crank by itself without pushing start button.
 

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First off, HAPPY 4TH OF JULY!
It's been several days since I put the "repaired" diode back in the bike, and it's running great!:clapping:
Since I have two more diodes on their way to me right now I figured I would test my theory. The bike was dirty from the 350 mile ride to Elko, so I decided to wash it. Since it had been such a pain in the butt, I gave it the hose too, not some weenie-ass spray bottle wash. I got everything good and wet, and it still starts up and runs perfectly.:eusa_dance:
I sure hope that my headaches can save someone else a bunch of trouble. Best wishes and safe riding.:flagwaver:
 
awesome news. make sure to update in a month or so...
 
First off, HAPPY 4TH OF JULY!
It's been several days since I put the "repaired" diode back in the bike, and it's running great!:clapping:
Since I have two more diodes on their way to me right now I figured I would test my theory. The bike was dirty from the 350 mile ride to Elko, so I decided to wash it. Since it had been such a pain in the butt, I gave it the hose too, not some weenie-ass spray bottle wash. I got everything good and wet, and it still starts up and runs perfectly.:eusa_dance:
I sure hope that my headaches can save someone else a bunch of trouble. Best wishes and safe riding.:flagwaver:

Glad to hear you may have solved your problem. Time will tell you.....
 
Guys,
Thanks for the support! Electrical problems can be a real nightmare, and this one was. I'll make sure I let you know how she's running in a month or so. Take care.
 
Folks, it's still running perfect and I now have 2 extra diodes. One is brand new, and the other is off a running Max that was parted out. If you are having any problems that seem like a bad diode, let me know and I will send you the brand new one to try out. No reason anybody else should end up with 2 extras!!
 
Folks, it's still running perfect and I now have 2 extra diodes. One is brand new, and the other is off a running Max that was parted out. If you are having any problems that seem like a bad diode, let me know and I will send you the brand new one to try out. No reason anybody else should end up with 2 extras!!

Thanks for posting your findings - it's always good to hear the final fix to a problem and in your case, I would have never thought to look at that component if it was me.

Now ride the hell out of it!

Mike
 

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