I lost two cylinders during a ride today!

This is such a great community. I've been reading for a few weeks now and I notice time and time again that you all give great advice and really know the technical details of these bikes! That said...

I had my '82 Maxim 550 out for a ride today, everything was running great until about 1.5 hours into the ride when I lost one cylinder. The bike was still behaving and I was very far from home, so I kept riding. About 2 miles from home I lost another one (more gradually this time). At that point I could not proceed at all...had to trailer it back to the shed. A friend of mine suggested that I might have fouled the spark plugs due to it being quite cold out today (~45 F). What do you guys think? I won't be able to pull the plugs until next weekend unfortunately. Any suggestions are very much appreciated!

I also have a (probably dumb) question about fuses. The fuse for my headlight keeps going out, but I'm having trouble wrapping my head around why. If there is extra resistance in my wires or the switch (because it's old), wouldn't that mean that less current could make it through and thus I could not exceed the rating of the fuse? This has stumped me for a while.

Thanks everyone!

 

on the loosing of 2 cyls pull the plugs see if you can figure out wich cyl you lost that will be a good starting point see if they have spark .it could be a coil or carbs messing up if we know wich cyls will make it a bit easier. you will need to change your oil when you figure it out to get the gas out of the oil if it was getting fuel

 

Thanks for the reply!

I could definitely smell unburnt gas after dropping the first cylinder. Would that make the crankcase become flooded after some time running?

 

crankcase might not be flooded but it will get in the oil and you don't need those problems. also do not try to start it back up with the plugs in if it has a float sticking that cyl could fill up with gas when you crank it it could bend a rod ect . when you pull the plug and crank it do not have the wire or plug anywhere where the spark could catch the fuel on fire . you probably know this but wanted to say it anyhow don't want to see anyone get hurt or hurt their bike

 

Hold on, conclusions are being jumped to.

You would smell unburned gas if you suddenly lost the fire. That alone doesn't mean a carb issue.

Yes, it could be a stuck float/flooding scenario as cutlass79500 is alluding to; it could also be a coil, a loose wire, loose plug caps; many things.

Pulling the plugs is the first diagnostic step. Determining what cylinders cut out would be the second diagnostic step. THEN, based on that information, we can try to figure out the cause.

No sense chasing an ignition issue in the carbs, or vice-versa.

Your headlight fuse blowing all the time is undoubtedly either a wiring issue or the original fusebox is failing.

 

Thanks, Fitz!

I actually some more information that might help: I just rebuilt the carbs a month ago and everything looked healthy in the carbs. However, they still haven't been perfectly synced. It's really hard to keep the bike running right when it is cold and the "choke" is on, but once it is warmed up it idles really nicely and the revs drop nice and quick.

I do tend to jump to conclusions, thanks for keeping me in check!

As for the headlight issue, the stock box was replaced by some PO...probably about 5 years ago. At some point before I bought it the headlight fuse had blown. When I put a new fuse in the headlight flickered on and off, high beams on and off, and the high indicator on and off. This persisted until I played with the hi/low switch a lot, at which point it would behave properly, then blow the fuse after a few hours. I'm assuming I just need to clean all the contacts in the switch and clean up the grounds, but my knowledge of the electrical stuff is sorely lacking compared to my knowledge of the carbs!

Thanks again for the help!