Cursed Bike?

[Lars Helly]

For months now I've been chasing some phantom issue. I rode 50 miles on my rebuilt 79 xs1100 special, and then things started getting weird. It started getting weak, so I revved it out to try to get past it (thought I had shifted early?) it went for a few seconds, then when I let off it stalled, and hasn't run right since. It would bog like crazy, wouldn't accelerate, wouldn't idle, and would jolt forward and clunk when I tried to ride it around my driveway from then on.

I changed the jets, nothing changed, needle position, no change, mixture screw replacement and broken tip removed, no change, diaphragms replaced, no change, floats tested and set, no change, coils replaced with Dynatec DC1-1, as well as new plugs wires and caps, no change, tested pickup coil wires, they had proper resistance, changed pods out, also tried no pods, no change. I feel like I'm losing my mind.

All of this done, and it didn't change the way it ran at all. The problem seemingly came from nothing, and nothing seems to fix it. This is my last resort. A cry for help to anyone with any idea of something else I could possibly try. I did notice some weird continuity things with my signal wires and power wires for the coils, but seeing as the bike ran for 50 miles with this setup it seems like something failed rather than was wired incorrectly? TCI? I don't know. I am open to any and all advice.

I attached a link to the video of it running. In the video, I'm giving it a ton of throttle to even get it to cough a little bit, and then it picks up and roars, so I let off. even when it's revved out its chopping a ton.

[Socer4m]

Hang in there, its usuallly something simple....guessing you should pull off the carbs, clean every jet opening with carb cleaner, check to see if the floats are not stuck closed, also check the pickup coils when warm for correct resistance, I had one go bad and it did a lot of the same symptons. Anyway, guessing its a carb issue or pickup coil. Also check the fuel filter that its not clogged, also try running it with the PRIME setting on the petcock,,,it can also help remedy fuel starvation.....


try to the prime petcock lever first
then check fuel filters, inline hopefully, if you dont have them inline after the petcocks get them on asap,,,very needed
then the pickup coils
pull a plug and ground it to check spark when cranking
carbs last since they are the most time consuming
keep us informed,,,hang inthere,,,Mike in S.Diego and Pa.

[Socer4m]

also forgot to tell you,,,check the exhaust header pipes for each cylinder after a quick warmup, if one is cold it can tell you which cylinder is not firing, just touch each one quickly or spray water and if one or more pipes are cold that helps diagnose a problem....

[Socer4m]

last thing, check the pickup coil wires when running, do a search,,,pull off the cover and jiggle when running if it changes rpm,,,a VERY COMMON PROBLEM on these bikes, do a search and should be on you tube or this site,,,maybe someone can chime in..........

[jetmechmarty]

What jets did you change? The pilot jets are susceptible to tiny bits of trash. In the video, is your choke open? If not, see if it runs with it open. If it does, the pilot jets aren’t open in all four.

[Radioguylogs]

last thing, check the pickup coil wires when running, do a search,,,pull off the cover and jiggle when running if it changes rpm,,,a VERY COMMON PROBLEM on these bikes, do a search and should be on you tube or this site,,,maybe someone can chime in..........

(1) That's what I would do first. Pull on the pickup wires when it is trying to run.

(2) Maybe drain the fuel bowls to see if all carbs have the same amount of fuel and the fuel is clean? You can turn on the petcock while you have each carb drain plug removed, and make sure fuel is flowing freely to each bowl.

[DEEBS11]

You would also need to check the spark plugs. Are they genuine NGK? Lots of fake, engine damaging plugs out there. "Changed the jets"....to Chinese junk? What other Chinese parts have been install during this rebuild? Are the coils genuine Dyna?

Back to the plugs. You should read them to see if any are fouled.

And as always, the advance unit wires could be broken internally. https://xs11.club/forum/repairs/batt...il-wire-repair

[DEEBS11]

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