I need help again!!!!

Ok, so this time. I'm driving to school on my oh so sweet 1985xj700nc and i notice the tach jumping down a little bit here and there. It gets worse and worse, pretty soon I can feel the bike cutting out a little bit. I think I might be out of gas even though I know I'm not so I switch to reserve but it doesn't help. The bike runs this way for about 5 miles. It's starting to get pretty bad but I had to make it to class. I came to a stop sign and had to let off the gas. It dies..... I wait like 30 seconds, and it starts right up and sounds fine. I drove it the 1 mile or so I had left to school and when I slow down to turn into the parking lot it dies again. After school, same thing, it runs about 5 miles, starts cutting out a little bit at a time and dies, then it starts up fine 10 seconds later. I checked the fuel filter and spark plugs.... Any ideas guys???

 

Electrical problem.

Your tach picks up it's signal from the lead to one of the coils. That signal is failing and makes the tach erratic and of course the bike misses because two cylinders aren't firing.

 

Failing coil? The one the tach is hooked to?

 

yai rode my 700 to school for the first time... no probs tho just a bit nipply(cold)

 

"Mom!" Schooter said "Nipply!" *lol* :lol:

 

lol, well you'd think it was nipply too, but i like cold weather, who knows, i may throw on my snowmobile helmet and ride into november

 

Maybe a simple fix.
If your gas cap is not venting you could have a vacume lock.
So you are basically running out of gas.
A simple thing to check.

 

thanks for the info guys! I'll check it out