Idle issues

[jaifresh]

Hey guys,

My xs was running alright a couple of days ago besides some popping on the left hand cylinder and not great fuel economy. It stills kick starts alright but when I rode it Into work this morning it tries to die at the lights when idleing after coming to a stop. I'll have to keep it alive with the throttle. It wasn't doing this before.

Am I right in saying its a mixture screw thing? The actual idle screw isn't the problem because it ran fine at low idle a couple of days ago.

Also the popping on the left bank is starting to annoy me. Is it usually the carb manifolds letting air in?

Really want to fix this at work before I go home tonight.

Thanks

Jai

 

[littlebill31]

If it's popping it is most likely a lean mixture, air leak. Try to locate it.
Also, make sure your carbs are synced. This too will cause popping.
Crack the throttle. Does it hang for a second, then go back to idle?
Start checking the intake bolts, exhaust bolts to see if they are loose. Intake barbs covered?

 

[jaifresh]

Barbs are covered, everything's tight. And yes it hangs for more than a second before it reaches idle rpm again. Do all these issues have to do with it dieing during idle?

 

[jim540]

While the engine is running reach down and try to move the throttle shaft up and down and fore and aft. If the idle and or popping changes there is a good chance that the carburetor housing is worn and that is where air is coming in leaning out the mixture and making the popping.

 

[jaifresh]

checked everything, managed to get the bike running pretty well. tightened all bolts put on new hose clamps around the carb manifolds and checked everything on the intake side for cracks and wear. everything looks in order.

the left bank is still popping when warm and even more so after pulling up to the lights.

i cant seem to find the problem is there anything else it could be?

thanks

 

[littlebill31]

It still sounds lean to me. Especially if it hangs for a second.
What type carbs? Are they jetted correctly? Mix screw adjusted correctly?

 

[jaifresh]

Bs34 mix screws I set to factory specs and the jets are stock. Other than me cleaning everything out I don't really know how to tune anything properly

 

[nj1639]

At one point while making carb adjustments- air, idle and sync, I was also changing out exhausts. After all was put back together I had a decell pop on the left cylinder. Now I know it had to be something with the exhaust of course. So I pulled the left pipe and muffler, resealed with high temp silicone at the muffler/header joint, let set well before running her again. Next time out I still had the decell pop.....wtf? Started double checking my carb settings starting at the air mix screws and found the left side was one full turn leaner than the right .....gremlins or an easily distracted idiot apparently were at work here. All's well now though I believe I may have to change out some butterfly shaft seals in the future.....