creeping idle after riding

this might be simple but just needs to be said. Make sure that you check what your butterflys look like when they have the throttle cable attatched. Sometimes the cable can pull too much when it is seated and will open the butterflys more than what you had bench syncd them to. I had a problem with mine at first wanting to idle up to 5k and then I found out that it idled fine with the cable disconected. I ened up bending the cable holder thing ontop of the carbs down to give some slack and it fixed the problem. Sure the idle screw can be backed out to lower a high idle but its not suppose to work like that

 

Issue resolved.

I went a different route to bench synch the butterflies. I backed out the idle adjustment screw all the way. Then, I set all 4 butterflies to be completely closed. After this I used the idle adjustment screw to set the opening on all 4 butterflies to what I thought was correct.

I put the carbs back on the bike, started her up and after turning down the idle I went to work synchronizing the carburetors. Fastest, easiest synch ever. The way I bench synched the carbs helpep in having all 4 open the same amount.

Hope this helps other members.

 

I'm wondering if this is a common problem with the XJ??? I'm having EXACTLY the same issues. Bike idle is set a bit high at 1500. It was set when the filter was out, but don't know if that really made a difference. I'll reset the idle when the bike cools down. Anyway it runs GREAT for 10-15 minutes then starts creeping higher (around 2200 RPM) when I'm shifting even if I close the throttle completely. It's also wanting to hold about 2200 RPM when I pull up at a stop light. IOW it just want to overspeed. Otherwise I couldn't be happier with a 10K mile bike that I paid $1K for.

 

Wyldman - Let the bike warm up to when the idle remains at 2200 RPM. Back down the idle adjustment screw and set it to 1000-1100 RPM.

After setting the idle, keep in mind that when the bike is first started, the idle will be around 500 - 600 so you'll need to use some choke to get the revs up until it warms up.

 

That's what I'm going to do, thanks.

The bike was ridden regularly but not any distance, maybe 25 miles per week or so. The more I'm riding it the more the idle problems are disappearing. I'll hold off a few more days and see how it does before I make the adj. Thanks again.

 

Do you guys find that your tach is accurate at the lower revs because I find that any reading below about 1200 on my tach is garbage. Basically what sounds like 500 reads as around 1000. So do you guys use dianostic tachs or some such tool to do your idle adjustments?

 

I don't use gauges but I have an ear for speed and I'd say it's pretty accurate.

 

mestnii

Buddy I took your advice and it worked great. I've had NO Idling problems since. Thanks for the help.

 

wyldman - glad to hear it helped.

fore4runner - my tach works fine at any RPM. I use it to set my idle

 

ive been having the exact opposite problem, after ten twenty minutes the idle will start to bog down and quit unless i constantly give it gas. so what could that be?

 

NOW I know who gave me the idle info! LOL Thanks again MESTNI, it's STILL working great!

 

i just went through this, thought i did it all right but had the same symptoms
this is how i fixed mine
get the carbs on the bench, look at the top of the bore by the butterflys
see a tiny hole there, move the idle screw till #3 butterfly just clears the hole
you should see the entire hole with the butterfly right at the edge of it,now use the sync screws to make 1,2 and 4 the same
heres the tricky part
back off the idle screw till 3 closes and then some, idle screw's not touching at all
now loosen the 2 butterfly screws and tighten them till they just touch, all of them,
now snap the throttle closed a few times (4 or 5 good slams) so the butterflys can find their own spot, move the idle screw till 3 just opens, tighten the butterfly screws just a bit now check the holes on the bore again and see if the idle screw closes them all at the same time
if not do it again
another thing it the springs on the sync screws, look real close there 2 sizes the thicker one goes under the screw
tighten the butterfly screws back up and snap the throttle again it should have a "thwack" sound unlike the first "thunk" sound
this whole thing would be easier if the butterflys were put in while the rack was still apart, then you wouldn't be fighting the sync screws
the whole thing takes longer to type than to do, worked for me, have fun

 

The Clymer book for my bike says not to use the tach to set the idle because it isn't accurate enough. I think every book for every bike I have had has said the same thing.

I use a photosensor tach that I got from Harbor Freight. I originally got it for checking RPMs on my lawn mowers when I was tuning them, but it has found new use for the Maxim.

 

I used the tach to set my idle as there is some leeway when setting it. Depending on outside temperature my idle speed fluctuates between 1000-1200 RPM, but she runs fantastic and I'm happy. I doubt that setting it to EXACTLY 1050 is going to give me huge performance gains.