Bike sputters, no power????

[BauersXS11SF]

Hey all, ive been noticing that when Ive been starting my bike up, it sputters and has no power, sometimes even dies. It seems like it takes off fine, ill be driving along (mostly after just starting it) and all of sudden its like it loses a cylinder, it has no power and when you rev it up, it sounds like the exhaust is only coming out one side of the bike (straight pipes out each side) Is it just because the bike is cold, or I noticed its always the left hand side of the bike, and the left carb boot is cracked worse than the right, could it be sucking in air?


Thanks.

[superdave]

sputter putter

is possible. next time it happens carefully check headder pipes for the cold one. than pull plug to that cyclinder for fouling or is it dry. that should give you an idea where to go from there !

[TopCatGr58]

Hey there Bauer,

Ooh boy, where to begin? The carb intakes can look badly cracked on the outside, but still be air tight, spray some WD-40, or carb cleaner, or starting fluid spray around them AFTER it's warmed up and idling, and listen for changes in rpm, if so then possilby a leak.

The left side carbs tend to get more gummed up than the right, due to parking on sidestand! If your choke/fuel enrichening port in the bowl is gummed/clogged, it can prevent fuel from being drawn into the enrichment circuit. ARE YOU USING THE FUEL ENRICHMENT lever when cold starting!?

The pilot circuit also contibutes to the just off idle throttle before you get into the mains....could also be clogged causing poor fuel flow, low power until you open throttle and access the mains!?

Could also be the pickup coils partially cutting out depending on rotation of timing plate and possible intermittent separation of wires.

If both left pipes #1-2 are cold, then it's lack of fuel to that side of the bank, if pipes 1-4 or 2-3 are cold, then it's possibly electrical, pick up coils, or ignition coils, or even TCI!? Like SD said, if plugs on cold cylinder are wet, then you're getting fuel but no spark! If they are dry, then no fuel...duh ! !

BTW, have you pulled the carbs and rebuilt/cleaned them thoroughly? The carbs are one of the 2 Achilles' heels in these machines! And don't worry about being wordy when writing followup reply after some diagnostic checks, the more we know, the more we can help!! Good Luck!
T.C.

[BauersXS11SF]

In reply to Topcat,

The thing that has me ruling out the carbs is that its not doing it all the time, I noticed today that it would do it shortly after a startup, even a warm one and it didnt do it every single time. I mainly notice it most in the mornings on my way to class, ill get about a block or so from my apt, and it will do it, it seems that if i let off the gas so it drops to idle and then gun it again, it clears up, which is why Im thinking its just sucking in too much air and not mixing properly. Its rather embarassing tho. I'm getting new plugs tom. damn Champions, they are all fine by look, but im a NGK guy and ill see if that clears it up, and while im down there, ill pick up some starting fluid spray and see if its the boots.


Thanks for all the help.

[Czekus21]

I would do the pickup coil check.

[John]

Ditto on the p/u coil wires.

[TopCatGr58]

Hey Bauer,
Champion plugs are fine, at least in my bike they are, been running RN9YC for years!

Unplug and plug the vacuum advance hose both in the end of the hose and the carb body! Then try riding it. IF it doesn't cut out so much or runs better, then it's pretty much the P/U coils, cause you've cut out the flexing of the wires by NOT allowing the timing plate to rotate with the vacuum advance!
T.C.

[BauersXS11SF]

I had the cover off the vacuum advance when I did the timing tensioner adjustment, the wires were both clean, and in extremely good condition.

I found today that a longer warmup on the bike made it quit doing it, I guess its just something with it being cold blooded. Never made it downtown for the new plugs, but im thinking the plugs are original so its definately time for a new pair.

Ive always had problems with champion, so I guess its just me LOL.