Carburetor / fuel / ignition issue with MZ Baghira

[Tigerboy]

So, last month my MZ Baghira turned over 66,666 km (yes, I know, I ride my bike a lot). It's now got about 68k on it.

Here's the intermittent problem I've been dealing with. Bike will run fine, and then rough, usually 30 miles into my riding. Lots of backfiring when I roll off on the throttle suggesting unspent fuel. The problem is hard to pinpoint as it appears random. There are times, on a trip, that the bike would run rough soon after heading out, but then after filling up, it has gone away, suggesting it was maybe bad gas. I've done the obvious, drain the float bowl to get rid of any water that might have settled. I've checked the fuel filter. I tried putting a gas treatment in my fuel that is supposed to clean out crap buildup in the carbs.

I'm also wondering, given the high miles on my MZ, if I'm overdue for a carb rebuild, especially given all the ethanol laced gas today. But the Carb on the MZ Baghira is an odd duck, a dual barrel carb with a single float bowl, that is really a nut that you loosen at the bottom to drain. I would not know where to get a rebuild kit for this.

I am also wondering if it's the coil, but the problem didn't seem temperature dependent. If it was the coil breaking down, then the bike would consistently run rough after so many miles into my trip and not when I first head out, which I have observed from time to time.

I'll check the sparkplug to make sure it's not fouled.

[DAVID THOMPSON]

the spade lug on my traveller on the coil was loose check them all

look at wires on back of main key switch

and do you have a lot of crap hanging on your key some people load a key down and it wallows the guts out of the switch

and relay 30 controls the whole bike if its going bad it can cause
big problems surprised at the miles if it has not been changed its where i would look
it turns on the whole bike and if the contacts are shot it will be a problem
link to drawings here
viewtopic.php?f=3&t=8382&p=44035&hilit=tony+idle#p44035

[Tigerboy]

Thanks! I have a feeling the problem is more likely electrical. I will be sure to check the cut-off Relay (which I guess you call Relay 30?)

I remember having a problem with my ignition prior. The whole bike would just die. I traced the problem to the ignition, a wire had come loose in the key unit and I had to solder it back into position. It's been fine since.

I should note that my entire bike doesn't die this time. It continues to run with the lights and everything but coughs and sputters and the excessive backfiring I get in this situation is from unspent fuel getting thru the cylinder and into the hot exhaust. This means it's not firing on every cycle. So, more likely a coil or ignition problem? I'll have to simply check that all connections are good, look for loose wires, etc.