Today during my ride at Oak Point my quad started to run really crappy. I was going through water fine then I started cat walking into water and spinning around. Got out of the water and it stalled, started it back up and it ran rough.

It ran ok and bad, off and on. Stopped and pulled the rear plug and the quad kept running, just the same as before. Pulled the front plug with the rear one plugged in and the motor stopped. So I was running on the rear cylinder alot today backfiring from the fuel burning in the exhaust pipe. Added some dielectic grease to the rear plug, on both ends. Tried the quad again, ran pretty good, it ran good till I hit some more water alot more water. After that it ran on the front cylinder the rest of the day.

I got back to the truck and plugged in my original CDI, still ran like crap. So its not my Dyna CDI. Loaded it on the trailer and got it back to my friends house. It started rough, ran kinda crappy, warmed it up some, started to run it around the yard, it seemed not to bad. Hit the field and tried it out some more and it was good, so I loaded it into the truck and thats where she is now.

Tomorrow I'm going to take the side plastic off, check my connections, see if I have spark on the rear cylinder, check the rear plug. Then go from there. I'll probably be posting for some suggestions on what I find tomorrow.

Any suggestions? I think its my connection, plug or plug wire somewhere. While on the trailer for 30 minutes it dried out some, that leads me to believe that water was getting in somewhere it shouldn't.

 

Mine did the same thing today. I also believed it was my dyna but it had the same problem with the stocker. It would go down to 1 cylinder and then if I would gun it , it would clear up and run great. It is also my rear cylinder because while it was running bad I killed it and pulled my front plug and it was dry aas can be. Mine started doing this after some serious mud bogging. But right now it only does it if I do an abrupt stop or hang a good wheelie and when it lands and I let off the throttle and get back on it it starts missing and backfiring. I'm not sure what it is. Post anything you figure out or try and I'll do the same.

 

In an attempt to dielectic my plugs I ummmm........removed my spark plug wire from my ignition coil while on the trail. I pulled the other one off my front cylinder and looked in the wire I pulled out. I noticed some weird fraying in the boot of the plug. It also took alot to come off, lol. So I've come to the conclusion that they don't come off. So no water would get in there, so that wasn't or isn't my problem. The ignition coil itself or the plugs going into it may have been the problem.

I'll take the ignition coils off my V-Force tomorrow and slam them on the brute. Then I'll start working on finding out whats wrong. I wonder what my dealer will charge me for new ignition coils, lol.

Also, how do you know if your spark is strong or weak? Would a weak spark cause a problem?

 

I'm still debating wether my problem is ignition or in my carbs because like I said in my other post. It only happens to me when I stop abrubtly or the drop from hanging a wheelie. It seems almost like my back carb is flooding itself and fouling the plug on the rear cylinder because when I mash the throttle it clears up. I had the airbox off the other day and maybe some dirt or something fell in and now its stuck in my needle and seat. I dunno, I'll mess with monday and maybe do some electrical waterproofing at the same time.

 

the best way to tell if you have week spark is that week spark will be sort yellow and lazy a strong spark will be bright white trust me you can tell the differance good luck[img]i/expressions/face-icon-small-smile.gif[/img]

 

I have spark on both cylinders now, it doesn't look right though. Its blue and yellow. I put a socket extension in the plug and put it close to the motor with the lights off. The blue and yellow spark tells me its not to strong from what I have read but, I wonder if using the socket extension is causing this? Its a pig to start, wonder if weak spark is the cause of this? I recently relocated my battery, would having the battery spliced into another wire be weakening my spark or does that even matter?

Thanks for the help.

 

I was about to post the same symptom. I went off a jump this weekend...as soon as I hit I could feel and hear a difference. I have had this happen in the past on whoops, but it would eventually work out after a few minutes. This time it ruined the rest of my trip and still has the same problem when I start it at home. I get no air out of the right pipe (rear) and my left pipe (front) backfires. I will pull the wire off the front and see if it kills the machine. I'm not much of a mechanic but can probably fix it if I knew what was wrong.....any new developments? No water was involved in my performance......it seems to have been caused by Jarring.

 

Check to see if the plug wire came out of the ignition coil somehow. It should be tight and they do not come out, the coil and spark plug wire are directly connected. You might have a bad wire or coil. Try swapping them around and see what happens.

My hard starting problem might be related to my snorkles, not enough air when starting it up and it floods itself maybe? Going to try starting the beast cold tonight with the airbox lid off.

 

Maybe it the coil. I rode with another bf750 this weekend says he lost a cylinder with the dyna cdi after it run fine for a few months. It happened before and dyna replaced it. This time the stocker did same thing. Turned out to be a damaged coil causing a shorted weak spark. The dealer says the stock coils might not be able to handle the cdis hotter spark. Now he's thinking of replacing the coils or just getting a dg5 and ebaying the dyna. Hey you might have stumbled on the real answer to dyna problems that they say are unproblems?

 

Interesting to say the least. I'll be putting dielectric grease on my plugs and wires going into the ignition coils tonight and tomorrow I'll be hitting water really hard to see if I can make her die.