hesitation over 20mph

I have a 1982 Xj750J. I did a test ride in the backyard for 2 miles in first gear and had no problems. So I pulled onto the road and no more than a 1/4 mile I had noticable hesitation problems. The carbs were just completely broken down and cleaned with the help of rick so I have a hard time believing it's a carb issue. I'm still waiting for her to cool down before I pull the plugs. I've tested the petock and it works fine. I tried riding with the gas tank taped open, same problem. Right now I have a hose (it's a little to long) going straight from my tank to the carbs because I though the filter was causing an issue. I've checked every component of the electrical system and they are all well within standards. I'm really stumped on this one and now it's the only thing keeping me in the garage. The weather is beautiful this weekend and i'm not sure how much of that we have left. Anyone have any other suggestions as to what could be causing this? I'll keep you posted on how the plug chop goes.

 

if your fuel line is too long that could be the problem. if there's any "high spots" or "hills" in the line, it's gonna trap air in there and not let the fuel flow. needs to be as straight a shot as possible, all "downhill" so to speak, from the petcock to the carbs. I'd try that first. I had the same problem and thats what it was for me.

 

After everything you've done; we've got to get this Bike right.

I'd pull the face off the Petcock and look-in to see that the Rubber Wafer Metering Gasket is in place and correctly oriented.

Next, I'd re-wire the Gang of Inline Fuses and solder all the splices.

Then, I'd road test with the Petcock in PRIME after you get it going.

See what that does for you.

 

I pulled the petcock last week and all was well. I'll try doing it in prime from the very beginning. Last time I switched it to prime mid-ride in an attempt to solve the problem. But i'll try it from the beginning and see what happens. As far as the soldering, i'm not much of a solderer. I'll check them tonight and have my dad look at em. He's a wiz with an iron. Do you really think it could be an electrical problem?

 

I don't know for sure; but I highly suspect an Electrical Problem.
When the bike was here; I Ohm-ed the Coils and the Right Hand Coil Ohm-ed out a little strange.
The Primary was Intermittent. Reading 2.0 or less several times and "Flat-lined" a few times, too.

When I got the Flat-line ... I touched the Multi's Probes together to be sure it wasn't a loose Probe.
Swapping-over Coils didn't help that Coils case because when I swapped-over the Plug-in's the bike wouldn't run.

This is where I began to wonder if BOTH Coils had an Intermittent problem.

 

thats been mentioned to me before too. Is there anyway to test that theory other than buying two new ones? Which reminds me that I need to mail your ignition box back to you. When I ohmed them out everything came out fine. Plus I rode fine for awhile at low speed. Could this be a transmission issue? Perhaps some kind of slipping?

 

If it was Clutch or Tranny you'd know it.
The Engine would rev and the Bike wouldn't go fast. You can actually feel a Clutch slipping. A slipping Clutch is distinct about letting you know its slipping.

Hesitation, on the other hand, usually means "Something Fuel Related" or "Ignition Related"

http://www.jcwhitney.com/autoparts/Item ... 0000289917

 

I pulled the petcock last week and all was well. I'll try doing it in prime from the very beginning. Last time I switched it to prime mid-ride in an attempt to solve the problem. But i'll try it from the beginning and see what happens. As far as the soldering, i'm not much of a solderer. I'll check them tonight and have my dad look at em. He's a wiz with an iron. Do you really think it could be an electrical problem?

 

I've got one of those exact things from sears. But i've had a few drinks at the pub tonight so i think it would be a bad idea to go riding around the streets holding that thing to my plug wires without a plate on my bike lol. I chopped the plugs earlier though and they were as follows #1 perfect, #2rich #3 Lean and #4 fine. However, when i took #3 off it fell apart in my hand. Literally cracked at the porcelain. Could that be a sign or cause of something? If I take the bike out tomorow and ride it for a while at high revs in first gear and everything is fine that would rule out electrical right?