low rpm problem....carbs???

[chemomche]

i have put some sh1ty gasoline into my kat(gsxs750f 89 GR78A) and had to clean the carbs and the sparkplugs therefore

now i have problems with the low rpm-just like one or more cyl don`t work
but at the middle and high rpm are good-all cyl working,wheels spining

the carbs are clean, the air/fuel screws set at 1 5/8 (as in the manual)

the coils were replaced last year and now checked again
charging system good

don`t kniw what to sheck more
have doubts for the carb syncronization

[The CyberPoet]

Reset the air-fuel screws to 2-3/8ths turns and check again (2-1/2 turns if there is alcohol in the fuel there).

Cheers
=-= The CyberPoet

[chemomche]

what did you mean by "alchohol in the fuel"?
i repleaced the whole fuel from the tank with shell v-power 100
and also put some addition for removing the carbon from the engine head


and just to ask
when unscewing the air/fuel screws i add more fuel or more air ??

[The CyberPoet]

what did you mean by "alchohol in the fuel"?

Standard fuel in the USA now has 10% alcohol in it (90% gasoline). Alcohol makes the mixture run leaner, which means the jetting should be slightly richer to compensate for it. This is a real problem for bikes that were already at the edge of being too lean in their mixtures. I have zero clue what the fuel contains where you are (pure gasoline or some mixture of alcohol + gasoline).

i repleaced the whole fuel from the tank with shell v-power 100
and also put some addition for removing the carbon from the engine head

and just to ask
when unscewing the air/fuel screws i add more fuel or more air ??

Unscrew = more fuel at idle.
You turn the screws down until they just start to resist (not very hard!), then start turning them back out and counting the turns (360 degrees = 1 turn).

Cheers
=-= The CyberPoet

[chemomche]

thanks man
i will try this weekend

and the other thing
the sparkplugs are white on the top-where the pasrk comes
but carbon black on the circle below the electrodes

[The CyberPoet]

and the other thing
the sparkplugs are white on the top-where the pasrk comes
but carbon black on the circle below the electrodes

Compare them to this webpage:
http://www.ngksparkplugs.com/tech_su...d.asp?mode=nml

Cheers
=-= The CyberPoet

[chemomche]

just like the first one(normal)

so if its normal it also means than the air/fuel mixture is good, isn`t it?


i still will check the carbs synchron of the drossel valves

[The CyberPoet]

just like the first one(normal)

so if its normal it also means than the air/fuel mixture is good, isn`t it?

If they have been that way for a long time, yes.
If something changed not very long ago, they may not have seen enough time to show the symptoms of running too lean

Cheers
=-= The CyberPoet

[chemomche]

10x again for the help

[curseboy]

sounds like one of your pilot jets might have got clogged or gummed up......Put a dash of fuel injector cleaner in your tank (or seafoam or whatever cleaner you want.)

This happened to me recently.

[chemomche]

sounds like one of your pilot jets might have got clogged or gummed up......Put a dash of fuel injector cleaner in your tank (or seafoam or whatever cleaner you want.)

This happened to me recently.

well i thought about that(happened to a friend recently)

opened the carbs,all was clean,all jets checked