I have read up on the idle hanging issues of our bikes and have lubed the throttle cables and it snaps back nicely. I can get the idle rock solid at 1500, as soon as I rev it some it will hang at about 2K-3K. Sometimes it will go down back to 1500 other times it will just stay and I will have to adjust the idle screw/knob again. I have the air/fuel mixture screws at 2.5 turns out.

once the carbs were cleaned and i put them back in, the seal from the airbox to the carbs is not perfect(very hard to get the airbox close to the carbs again), there is a slight opening where that little spring seals to the carbs. Could that be reason the idle hangs?

Once moving it runs good, just the idle wont drop and i dont like taking off at 3K.

Any thoughts?

Back ground. 2003 15000 miles, sat for 3 years by previous owner. had the carbs cleaned and the shop didnt clean the air mixture jets. removed the caps and cleaned them out and the bike started, from that point its been a battle to get the idle to correctly drop to 1500. Clean out the tank of old gas, inline fuel filter, and new petcock.

once the carbs were cleaned and i put them back in, the seal from the airbox to the carbs is not perfect(very hard to get the airbox close to the carbs again), there is a slight opening where that little spring seals to the carbs. Could that be reason the idle hangs?


You need to fix that. You are sucking in unfltered air through that opening as well as leaning out your mixture by letting too much air in. A hanging throttle as you describe is a classic sign of a too lean idle mixture circuit.

Don't just richen out the mixture to fix the problem. Fix the intake gap between the carb and airbox first, then work from there.

http://faq.ninja250.org/wiki/How_do_I_adjust_the_idle_mixture%3F

Ok. will check that and reply back with what I found.

Jonathan

gl... I've heard that spring joint can be a royal PITA to get back on correctly.

yes, please let us know how it turns out.

That's good advice. Fix that then get back to us!

Finally got around to seating the airbox again. The right side was definitely not seated. i took off the rubber seal and set it in some hot water to have the rubber return to normal, since it was pinched and distorted. Got eveything on and sealed nicely.

warmed the bike up and tried to set the idle and its still hanging high. Put the bike in gear and let the clutch out some and the idle drops to 1500 and stays. I verified that I have the air mixture screws at 2.5 turns out.

What else should I check or try at this point?

I thought you meant the hose that connects the carbs to the engine...that will definitely create a lean situation, whereas what you just fixed just fixed the issue with unfiltered air going into your engine.

Check your vacuum chamber diaphragm...if it's damaged or not seated correctly, hanging idle may be an issue.

Here is a picture of what it looks like from a different carb, but it is almost exactly the same.

http://members.optushome.com.au/cbr250forum/CARB2X.JPG

damn, looks like i am taking the carbs off again. I will check that and the only other thing i didnt check was the throttle sync and float level since i didnt touch those. I will check that too. is there a good write up for setting the float level or at least checking it?

Back ground. 2003 15000 miles, sat for 3 years by previous owner. had the carbs cleaned and the shop didnt clean the air mixture jets. removed the caps and cleaned them out and the bike started, from that point its been a battle to get the idle to correctly drop to 1500. Clean out the tank of old gas, inline fuel filter, and new petcock.

sounds like the pilot jets are clogged with crap in the gas from sitting for a number of years. Usually at this point, removing the carbs and cleaning/replacing the pilot jets are the only cure.

You could try draining the float bowls, then running some Seafoam in the gas to see if it will break down the crude in the carbs, but after this much time I question if it would help. It is easier than removing the carbs, though. :)

is there a good write up for setting the float level or at least checking it?

http://faq.ninja250.org/wiki/How_do_I_work_on_the_carbs%3F

The carbs were cleaned about a month ago by a shop. Didnt do a good job to me, so I took the jets out and they were all clean. then only thing was not clean was the air mixture, which was really gummed up. Tank was cleaned out new gas, etc. its just not idling good. I will check the carb sync, floats and diaphram.

Or i might just get new jets all together. I am not going to mod this bike since its going to be my girls, soon as I get it in proper running order. I just picked up an 08 250 :O)

then only thing was not clean was the air mixture, which was really gummed up.

mind showing a picture of this part?

kkim, its part 16014 that was gummed up. once i cleaned them the bike ran without choke. now its just idling bad.

What should I replace in the way of jets? I.E 16009, 92063, 92064.


http://webservices.motorsportdealers.com/parts/partImages/KUS/2/C19/C1974/E1612.Gif

when you take out 16014 to clean, be sure to shoot out the passages with some compressed air, if you've got a compressor.

pilot jet is 92064. also, blow it out and the passages it screws into with compressed air.

be careful when working with compressed air. use safety glasses to shield your eyes from liquids that may fly around.... ask me how I know! :rolleyes:

besides 92064, should i replace anything else? or just make sure eveything is clean beyond the 92064? thanks for all the help kkim.

it sounds like the rest of your jetting is working fine. the problem seems to be in the pilot jet or mixture circuit.

please report back with what you find.

Placed the order for new jets 92064. Once installed and everything is checked and cleaned I will post back. Thanks again kkim.

wish you luck!! :thumbup:

be careful when working with compressed air. use safety glasses to shield your eyes from liquids that may fly around.... ask me how I know! :rolleyes:

how did you know kkim? :D
Posted via Mobile Device

how did you know kkim? :D
Posted via Mobile Device

wut??
:nerd:

Some people think you don't need the O-ring under the mixture screw, but you do. Make sure it is still good. That can cause your problem too.

thanks for the pointer. I will make sure and check that out too. didnt realize that was there, it might still be in the hole.

Finally got around to get the new jets installed and it appears that everything carb related is working as it should. I made sure eveything was sealed (airbox/carb/head) and it fired right up. warmed it up and set the idle and was able to ride it.

Once the bike it warm the clutch though is grabbing when i have the clutch pulled. I think it might be oil related or clutch cable related. But its strange that the shifting works good cold, and then grabs when its hot when engaging it in first. Thoughts on this issue?

Finally got around to get the new jets installed and it appears that everything carb related is working as it should. I made sure eveything was sealed (airbox/carb/head) and it fired right up. warmed it up and set the idle and was able to ride it.

Once the bike it warm the clutch though is grabbing when i have the clutch pulled. I think it might be oil related or clutch cable related. But its strange that the shifting works good cold, and then grabs when its hot when engaging it in first. Thoughts on this issue?

When you say it grabs, do you mean it jumps or jolts forward a bit when you put it in first from neutral? Or do you actually stall when you put it in first?

If it's the later situation, adjust your clutch cable first and see how that changes. If it's the first, it is completely normal.

when i put it in gear, it grabs and then starts to stall, then stalls. I will check the cable.

I agree... check and adjust the clutch cable for proper end free play.

if that's not the problem, when was the last time the oil in the engine was changed?

Changed the oil about 10 miles ago, but i am going to change it again with rotella this weekend. I will adjust the cable and report back, again.

adjusted the clutch cable and it appears to be working good.

The other strange thing that is coming up is that the choke doesnt work all the time. I can start the bike with just turning the throttle some. But if I pull the choke and try to start it it wont. Wonder if I need to turn in the air mixture screws some. Maybe too much fuel. I have them at 2.5 turns out. once the is warm it runs great and idles smooth at 1300. blip the throttle and it jumps up and down nice. thoughts?

if it starts (with or w/o choke), warms up nicely and runs well once warm, I wouldn't touch anything. If it begins to be a problem the way it is, then investigate further. Until that time, ride and enjoy the bike.

Congrats on fixing your problems.
:thumbup:

sounds good. Thanks for all your help. My girl has started to ride and likes it.

np... glad to be of some help.


remember... MSF and ATGATT