650r carb adjustment

[CAPONE650R]

Hello guys been tryna figure out how to sync the carbs I’ve tried the bottle method but I don’t know where to adjust it in the carb also how many turns should the mixture screw be turned?

[♠️ M77]

Hey,
Mixture screws should be near the bottom of the carbs , usually hiding under a plug to stop dirt going to it.
Generally 2.5 turns out from fully seated , then use fresh spark plugs.  Go for a ride and come back.

Use the spark plugs to indicate whether:

• Center cone (white porcelain) is brown = Jet is good, bike is not leaning out on full throttle. And also the slide needles should be factory or 1 step AWAY from the carb base (not going further in to it)
• The middle ring = If its sooty black very dark , indicates its idling a bit rich, this is where you can fine tune mixture a little bit.

The drain “pipe” for draining fuel out of the bowls,  look at the float bowl, there should be a line there.  There is a youtube video somewhere that shows how to check float levels are good using a “clear hose” method.

The sync of the butterflies  , if one pot flows more air than the other, find a carb cleaner => spray some in to the opening, if one side drips than the other one , it usually means that butterfly is a bit more open than the other.  I would not be surprised if the rear is a tiny bit more open than the front as the rear engine gets the hottest.  (air atmosphere flows less to the back) hence rear also tends to have either equal jet to front or 1 size up max.

Pilot jets don’t need changing.

[Author]

Posts

[CAPONE650R]

Hello guys been tryna figure out how to sync the carbs I’ve tried the bottle method but I don’t know where to adjust it in the carb also how many turns should the mixture screw be turned?

[♠️ M77]

Hey,
Mixture screws should be near the bottom of the carbs , usually hiding under a plug to stop dirt going to it.
Generally 2.5 turns out from fully seated , then use fresh spark plugs.  Go for a ride and come back.

Use the spark plugs to indicate whether:

• Center cone (white porcelain) is brown = Jet is good, bike is not leaning out on full throttle. And also the slide needles should be factory or 1 step AWAY from the carb base (not going further in to it)
• The middle ring = If its sooty black very dark , indicates its idling a bit rich, this is where you can fine tune mixture a little bit.

The drain “pipe” for draining fuel out of the bowls,  look at the float bowl, there should be a line there.  There is a youtube video somewhere that shows how to check float levels are good using a “clear hose” method.

The sync of the butterflies  , if one pot flows more air than the other, find a carb cleaner => spray some in to the opening, if one side drips than the other one , it usually means that butterfly is a bit more open than the other.  I would not be surprised if the rear is a tiny bit more open than the front as the rear engine gets the hottest.  (air atmosphere flows less to the back) hence rear also tends to have either equal jet to front or 1 size up max.

Pilot jets don’t need changing.

[Author]

Posts