Black dry spark plugs and starting issues on cold

[Eal90]

Hi,

I did try to find post about this exactly, but couldn't 

Now I started my driving season at monday.
Straightway begins starting issues at cold, first thing I did change my Spark plugs(They were black and dry).
What can cause this, too lean mixture and what to do about it?
At this winter I did clean my carburetor and didin't touch any adjustment(did change one pilot jet cause somebody broke head of it).
Now it starts fine with new spark plugs but I guess problem wont be solved with that and it'll come back to haunt me.
I'll put picture of my black spark plugs later today.

[Big Rich]

Black plugs usually indicate a rich mixture, but that sounds odd to me with stock jets. How old is your air filter? And when were your valves checked last?

[Eal90]

I did check my valves also couple months ago. They are fine after I did change exhaust valve shim to thinner.
Also airfilter was clean so I didint do nothing to it(did blow with air last summer). Dunno how old it is, I'm gonna replace it in couple weeks so it'll be new(have to change fuel hoses also at same time..)
And what about mixture screws, does they help for this situtiation?



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[Big Rich]

I dunno man.... that's a pretty good looking plug in my opinion. Does it sit and idle for long periods, or do you baby the throttle when riding? The electrode looks a little darker than what I'd prefer, so that's why I mention it. And the threads being dark like that just means they are used, but not a big deal.

I think putting new plugs in is just hiding a problem somewhere else - hence why I asked about the air filter, valves, burning oil, etc.

[Eal90]

Yeah. You are probably right but I have to change sparkplugs like every four months.. And for another questions: I drive everyday mininum 30km~ for work. Yeah it sits for half year because there is this little thing called winter.. Wtf is baby throttling 

[Iarn]

When Big Rich refers to babying the throttle, I'm pretty sure he's referring to not revving your engine up very high, shifting at low RPM (4-4.5k-ish) and the like.

The plug looks fine to me. It's clean, not white nor sooty. I'm inclined to agree with Rich, another problem some where else.

That gap looks huge in the picture. Have you measured that?

[floatingLomas]

I hadn't run my bike in like a month, and it took a good minute or so of cranking before she fired.  After that, she started up beautifully after sitting for two days, then again two days later.

Apparently the fuel will evaporate out of the bowls over time, so it can take some time/cranking to refill to the point that it will fire properly.  I'd bet flipping it to 'prime' for the first startup after sitting awhile would help with that, since fuel can only flow with a vacuum when in the 'on' position.

...Or maybe she was just pissed at me for ignoring her.