My yamahai xs 1100 engine has developed a serious misfire.when the carbs rubber balance pipe between 2 and 3 is disconnected,the engine picks up on the 4 cylinders but as soon as the pipe is re-connected the engine starts to pop pop through the exhaust really bad.I,ve tried everything from changing the carbs twice to fitting new rectifier etc.Also,since this problem has developed the 2 outside exhaust pipes have gone deep blue and purple.(just like we don,t want!!) etc.I,m at my wits end now and no-one seems to have any answers to this problem.--ps--its a 100 yamaha xs and not what i had to list as this engine was,nt listed.remember its an 1100 xs
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Re: my yamahai xs 100 engine has developed a serious
Does it run and ride fine with the balance pipe disconnected?
Have you checked your ignition coils. If you have a manual, check which coils fire which cylinders. Does this tie up with the two cylinders that are getting hotter, (are the other to staying cool/cold?) each coil provides the spark for two cylinders. You can swap the coils and see if the other two pipes go blue, that way you know a set of coils is bad. It sound like you have done everything on the fuel side, which leaves mechanical or electrical. Dont forget to check/clean/change the simple things such as the spark plugs and caps.
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You probably have varnish build up in the carburetors, causing restricted air flow, and therefore the engine is running too lean, especially on the right side, and a lean running engine will run hot at the exhaust. It only idles when the choke is on because the choke creates a richer fuel supply. A can or two of commercial fuel cleaner through the fuel supply may get the engine's jet's orifices cleaned out. Otherwise, overhaul the carbs. Hey, nice old bike, though. Good luck
They will be just on the intake engine side of the carbs.
I think the Kwaka still had rubber push on caps, some bikes have screw or allen bolts with a 5mm thread that you screw some adapter tubes into(these often come with the vac gauges)
It looks like you can still get new manifolds and "O" rings at Babbitts. Go to www.babbittsonline.com/parts/veiwbybrand/parts.aspx Look at the "air cleaner" page. There is no easy way to remove the carbs. I would remove the air cleaner assembly then you have some room to work. If possible, remover the carbs as a set. This will mean fewer parts to reassemble and a lesser chance of throwing the carbs out of sync and out of balance. If the carbs get out of sync and out of balance the engine will run poorly. Backfire through the carbs may occur and that can set the bike on fire really quick if the air filter is not in place. Have a fire extinguisher at hand when you start up the bike. I am serious. Please rate my answer...
It is part of a detent mechanism for the choke. No, all 4 carbs do not have them, only 1. Here is a link to Yamaha's website, where you can pull up a diagram of your bike's carbs. The ball is #10 and there is also a spring with it. http://www.yamaha-motor.com/sport/parts/home.aspx They are saying there are 2 balls and 2 springs, but I do not remember them having 2. I also don't see another #10 or #11 on the picture anywhere. You should be able to look at the rod that connects all the chokes together and see if there are 2 sets of dimples for the balls. Obviously there will be one set in carb #1, if you find another set of dimples for a detent ball, then there indeed would be 2. Also, the carb body would be drilled for the spring and ball like the #1 carb is. Thanks RSRBOB
- Remove the seats, the lower and both side fairing middel sections
- rRemove the fuel tank ( don't forget to close the fuel **** first ) and take care of the fuel level sensor lead
- Remove the battery leads
- Remove the 4 air filter casing bolts
- Remove the crankcase breater hose between air filter case and cylinder head cover
- Loosen the clamping bands on each end of the 4 carbs ( thus 8 bands )
- Pull the airbox to the rear and disengage the rubber joints from the 4 carbs
- Pull the carbs to the rear to disengage them from the rubber inlet-pipes.
- Move the carns to the right to have acces to loosen and disconnect the throttle cables.
- If there is an evaporative emission tube, disconnect it from the carbs, AFTER marking their place!
- Remove the carbs to the right side. That's quite difficult, there is not much place, be carefull.
to replace, just invert this way of work.
When engaging the carbs in the inlet-pipes, you have to feel them knok down at the end of the pipe fitting.
Be sure to tight the clamps correctly to avoid at 100% air leaks.
An air leak between carbs and engine will lean your mixture and will cause serious engine damage!