FCR problems

[speedy400]

Hi, gezz I used to be a wiz with carbs but I'm stumped. About 3 weeks ago it just started doing this one day basically. I am way too rich at 1 throttle position, about 1/8th-1/4 throttle, I tried messing with the air screw, pilot, and needle, nothing seems to help. I removed the air filter and rode it around like that for a little bit and it seemed to help quite a bit but it still wasnt perfect. what its doing is just coughing and popping like crazy(popping because extra fuel in the pipe...right?). Well now I'm starting to think the accelerator pump is giving it way too much fuel. Any ideas at all would be just peachy.thanks-darren

edit- also it likes to run like its flooded when I just hit the throttle.

[MIKE400EX]

Remove the carb adaptor/bell on the air filter end and see if something is blocking the slow air port. It's the one on the left-bottom side when looking at the air filter end of the carb. If it acts up at constant speed/rpm, it shouldn't be the acc. pump, but that may just make matters worse when you up the RPM's and the pump squirts. Good Luck!

[speedy400]

Well.... I removed the "slow jet" seemed ok but I cleaned it anyways, I also cleaned out the jet right next to it, no progress in the problem. A friend of mine suggested the floats? if that would be possible, anyone know what the specs are and how to adjust em? thanks-darren

[speedy400]

So I got an idea, I noticed a quite noticeable air leak in the slipon to the header...? but wouldnt that make it lean? eh oh well I plugged it up tonight and will be dry tmorrow, anyone wanna bet if it'll work or not?thanks-darren

[Colby@C&DRacing]

YA a bad air leak on the pipe will cause that. :)

[pnut420]

Originally posted by speedy400
So I got an idea, I noticed a quite noticeable air leak in the slipon to the header...? but wouldnt that make it lean? eh oh well I plugged it up tonight and will be dry tmorrow, anyone wanna bet if it'll work or not?thanks-darren

Actually when it popping and what not usually that is running lean. Do a plug check and see what it looks like and then go from there. You could be rich up up top and lean down low, and going from a rich condition to lean alll of a sudden willl cause popping

[speedy400]

Well the exhaust hole fix didnt do anything, if anything it seemed to make it worse:(. The thing I know is it was running much better when I had took off the air filter, so it must be just rich in one spot, because otherwise it'd be lean popping like mad if it was popping from being lean in the 1st place. The one thing that really confuses me is it ran perfect the whole rest of the summer with no changes needed what so ever, and before it was the same temp and moisture in the air and all, as it is now. is there anyway I could check if it was the accel pump? would temperarely dissconnecting the pump linkage to see if it helps be a good idea?thanks!-darren

[speedy400]

well..... :mad: ...I tried 7 more jetting combos. I also tried temp unhooking the accel pump... nothing. I was thinking of just taking the carb apart and cleaning it. Also I removed the air filter to make sure that it was running better with no air filter, dosnt make any diffrence, my fault... so I think thats the last option to clean the carb...?-darren

[speedy400]

this has got to be one of the worse days I've had in awhile.. turns out when I rode with the accel pump linkage just hanging, it fell out somewhere in my trails:mad: . So I cleaned it anyways, used almost a whole thing of spray carb cleaner. It still runs the same as before. To make it worse, I lost one of my extra pilot jets, and I noticed its puffing just a tad of blue smoke....just peachy..arg. So the problem is not yet fixed, anyone have anyother ideas?

[cals400ex]

make sure there isn't an air leak where the headers go in the head.
make sure your intake boot that connects to the carb has a good o-ring on it and it isn't cracked and make sure it is tight.

i would take the whole carb apart and remove all the jets/ accel pump and clean the heck out of it with carb cleaner.

possibly change the spark plug and try to get a plug reading.

maybe your ignition box is failing you.

what throttle position is it running bad at?

[speedy400]

Originally posted by cals400ex
make sure there isn't an air leak where the headers go in the head.
make sure your intake boot that connects to the carb has a good o-ring on it and it isn't cracked and make sure it is tight.

i would take the whole carb apart and remove all the jets/ accel pump and clean the heck out of it with carb cleaner.

possibly change the spark plug and try to get a plug reading.

maybe your ignition box is failing you.

what throttle position is it running bad at?
I'm sure there is no leak in the headers, there is just a tiny leak between the hmf slip on and the header but nothing that would make any diffrence. I accually did take the whole carb apart and removed everything last night and used a whole thing of carb cleaner spray bottle on it, it didnt seem to make much of a diffrence, I also did a plug check a few times, seems to be telling me its running perfect, just a tad lighter then cardboard. the throttle position problem is about 1/6th throttle I'd guess. Thats a good idea about the ignition box, would it act like this if it has a problem? should I try spraying the box with electrical cleaner maybe? thanks-darren

[speedy400]

well, I think you might be right once again cal, seems to be ignition box/electrical problem, I could just Barely get it going a few min ago, it just didnt want to start at all, it'd turn over and all just didnt want to fire, then when I did get it going, it seems to be getting worse every time I start it now is like 1/8th throttle to about 1/3rd throttle, all popping and such.is this average symptoms?-darren

[cals400ex]

i am not sure how it would exactly act if it was the ignition box. i never really had the problem. i was just throwing out suggestions. if the bike is really hard to start, i would probably go and replace the plug first.