this has happend twice today.


i normaly let my bike warm up a good amount of time (until the rockers are warm to the touch)


2 different times today i had my usual warm up then went for a ride, parked somewhere for only 20 min or so then when back to start the bike and go and she turned over i gave her throttle, a cloud of black smoke billowed outta the exhaust and she started up; but i had to keep the throttle open a little in order to keep her runnin, if not that then i had to pull the choke out, but the bike was already warm.


i recently replaced the ECT i think its called? so i'm pritty sure it can't be that. bike seems to run fine when its runnin or at lights.


i haven't checked my plugs yet to see if i'm runnin to rich (becuase of the black smoke) but why would the choke need to be pulled to keep it runnin if it was runnin rich anyway?


i have a 4 month new inline fuel filter in the line
any ideas????

 

Sounds like its loading up before you shut it down. Running real rich as your riding then you shut down the bike and you have some extra fuel and carbon. So when you fire it up out rolls the black smoke. I could be way off on this but its my thoughts. And the reason for the choke and throttle on start up could be that your a little lean at start up and idle but out on the road at high rpm and running range your running rich and loading up if you say come off the free way or state route shoot in to a station and shut it down.

 

Firstly, your plugs are gonna show the average burn throughout your riding, tilting towards where you spend most of your time(crusing rpm etc..). It's not gonna show the burn at idle.
Secondy, yeah...it sounds like you were loaded up. If it persists, I'd check your idle circuit and maybe adjust the air screw.

 

sounds like it's loadin' up with fuel...btw,what's an ECT?

 

Would check the choke cable .. Sounds like loaded up and/or running rich..

 

this sounds right on the money! how do i fix it??

ECS?? i forget what its called, electronic camshaft sensor or something like that?? just a little plug inn do-dad that effects start and stops that i was having an issue with

 

here is my thought, adjust the mixture screw to bring fuel level down and increase idle screw to bring idle up...how does that sound to anyone???

i would really prefer to not pull my carb and re-jet, the bike was tuned for 2 1/4 inch pipe when i got it and when i made my own i made them 2" and put a different breather on it, but i also had messed with the mixture and idle screw so maybe "un-messing" with it would solve my problem??

 

Hate to be the bearer of potential bad news. But if you downsized your pipes you are most likely running rich and will have to rejet. I don't think adjusting the screws will give you enough adjustment for the loss of pipe size. It is only a 1/4 inch, but it is the total length of the pipe and that translates into a fairly large amount of scavenging volume that you lost.

 

Yeah if the pilot jet size wasn't changed or messed with it sounds like you need to adjust it's adjustment screw to achieve the correct A/F mixture.

The pilot jet fine tunes the amount of air/fuel passing through the idle system, and can impact how the bike idles and runs up to about 1/8th throttle. If the jet is too large, or adjusted too rich it will cause the bike to load up at idle and low speed, especially if the choke is used.

Also check the choke cable (or as it's called now 'enrichener') to make sure it is working correctly.

This is assuming you are running a carb'd bike.

If it's EFI it's a different set of headaches.

 

ok so, yes i have a cv carb on my bike

what i think i'm hearing is that i need to pull the carb, put the idle mixture screw back to the "stock" setting (2 turns out) see what size the piolit jet is and go down 1 size. does that sound right?

if so, i've been runnin this setup a while, one more weekend won't hurt ya think???