I just installed and synced new 28mm mikuni carbs. I turned both idle screws until they rested on the slides, then backed them off a bit. When I started the bike, it revved much higher than normal, so I backed off the idle screw a half turn. It still revved too high, so I turned the idle screws all the way out. It got a little better, but still seems to idle too high.
Both air screws are turned 1.25 turns out, and I'm "thinking" my slides may not be dropping down far enough. I read that the end of a small drill bit should be able to fit between the bottom of the slide and the slide passage. I've attached a picture of the slide dropped all the way down/throttle closed. Any help would be great.
Do the slides audibly bottom out on the carburetor with the idle screws out all the way? If not, you might not have enough slack at the throttle cable or it could even be the cable is pulled out of the carburetor or junction a bit.
Check those before you look at jets.
I can hear them bottom out when they drop. They both raise and lower at the same rate. I'll check the junction and tops of the carbs to make sure they are seated. I'm moving from stock to newer mikuni carbs. I "think" I remember the stock slides were lower when the throttle was closed. Thanks man!
Try to see if the front edge of the slide is down closed or almost closed against the floor of the carb. The slides should be only a few thou above fully closed. Check the idle (slide) screws first to be sure they are not holding the slides up. Then check the cable adjusters on the slide tops and in line if there's one there and then at the throttle if there's an adjuster there.
Just pop off the carb, be careful not to pull on the cable and spin it around and look for a gap on the engine side of the slide. need to start with no gap then add in idle screw. if they're closed and still revs high you have too lean of jetting and or air leak or a combination of both...
Chuck
if it's a stock cable, won't work with the new VM28's.
Yeah. I adjusted the cable and was able to lower the slides all the way down. I started it up and it idles much lower now. I cut the engine off to adjust the idle screws a half turn, but cant get it started again. I guess I may have flooded it.
I changed the plugs and still won't start up. Is the best way to fix possible flooding to pull the plugs and crank it over several times?
What are these carbs on?
Did you use the stock jetting specs from the old 28mm carbs?
These carbs are not pre-jetted for any RD, R5 or DS.
C
Quote from: MRDRcycle on November 16, 2019, 05:09:55 PM
I changed the plugs and still won't start up. Is the best way to fix possible flooding to pull the plugs and crank it over several times?
remove plugs crank it over several times and replace plugs - this is what I do-
I think I read where you can crack the throttle open 1/4 turn and continue holding it open while kicking until the bike starts - this may also work if your bike is flooded
Good Luck!