runnung rough, cant figure it out

bone head wrote: . . . what is a plug chop?

Sometimes referred to as throttle-chop testing, the objective is to see what the business ends of the spark plugs look like under various running conditions.

Here's an example:
Say you want to see whether a particular main jet size is too big or too small or just right.
And you are already aware that main jet size governs fuel mixture at wide-open throttle.
So you are wondering how to tell what the spark plugs are looking like inside the combustion chamber while the bike is running at wide-open throttle.

And the valve clearances are correct, and each valve is seating fully closed as it's supposed to; and compression is acceptable; and all fuel levels are within spec as confirmed by clear tube testing; and fuel supply to carbs is adequate; and spark quality (ignition strength) is fat-blue -- not weak wimpy orange; and ignition timing is spot on; and that the timing advancer is properly functioning; etc., etc., etc, meaning carb tuning comes LAST after first assuring that compression components and ignition components are all already up to snuff.

Likely the most dangerous part of throttle-chop testing --
Being safety-conscious, ride at wide-open throttle long enough for the spark plugs to develop whatever color they're showing inside the combustion chamber at wide-open throttle. Again -- BE SAFETY-CONSCIOUS!

Simply coming to a stop by slowing down in the usual manner allows the plugs to change color to something besides their wide-open throttle color.

But, while riding at wide-open throttle, you can SIMULTANEOUSLY -- drum-roll -- this is the throttle-chop test procedure:
• Close the throttle (aka chop the throttle);
• Kill the ignition;
• Disengage the clutch (squeeze the clutch lever);
• Coast or brake to a stop;
• Remove and read each spark plug.

Practice the above procedure several times at slower road-speeds to get the knack and feel for it in order to more safely repeat it at a higher speed.

Remove and inspect each spark plug to determine the plug condition (i.e., read the plug), which will reveal whatever effect the fuel mixture is having on the plug at wide-open throttle.

Here's a tip.
Coming to a stop aboard the bike after the throttle chop will usually be at road-side or hopefully in a somewhat safer position such as a pull-off area or maybe a parking lot -- somewhere you aren't in danger of getting run over while kneeling by the bike removing/reading/replacing the spark plugs.

And yes, the plugs are quite hot, so finger burning is a distinct possibility.
But of course, you were thinking ahead, and carried along not only a plug wrench, but also -- another drum roll -- a short length of hose (likely oil hose) with which to remove the loosened hot spark plug from the hot engine head.

And which short length of hose may also be used to help with a burn-free re-installation of the spark plugs.

The throttle-chop test procedure will be repeated with each different main jet size until the porridge is not too hot and not too cold, but just right.

Good Fortune!

bone head wrote: alright i got the bike running alot better. idles good, runs good at wide open throttle, and good in mid range BUT if i just touch the throttle slightly it bogs down. but when i get to 1/4 throttle it flatens out. iv got #92 primary and 78 for pilot jets and needle is at stock. any suggestions. do you think it would be the pilot even though it idles perfect?

if i just touch the throttle slightly it bogs down -- would suspect that the pilot circuits are not perfectly clean.

Good Fortune!

sorry i havent responded, my daughter was born shortly after my last post and i havent had internet access.
but i have not done a chop test yet. i did clean carbs again paying special attention to pilot circuit but nothing has changed.
the filters i am running are just cheap off brand filters, and i talked to the guy at a local shop and he said the cheap filters have a lip inside the boot where it buts up to the carb that blocks air flow from hitting walls of carb. witch i do see now that it has bean pointed out. So i orderd a set of uni air filters and am waiting for them so we'll see what happens with them.
thank you for your input

ok i bit the bullet and bought a set of vm carbs from summit. there on back order should have them by the end of the month. should have listened to you all at the beginning.