random Higher Idle

[Eddie Gravy]

It took 4 days and some goofing off to get my Maha to LA. on average 25 miles to the gallon. not real satisfied with that. cylinder 2 spark plug had a white ash on it. not bad enough to cause problems, though its carb is the vaccum hosed carb.

But i do have a ghost in the machine. at random times while stopped she would idle around 3 grand (7 or 8 times). been in LA for 5 days and had an idle up at 2 grand(once or twice).

she normally idles a hair more than 1 grand.

what could be causing the speratic idle. now its only done it a hand full of times.

yes i throttled off and on while it idled high, its not the cable, its lubed.

what could it be?

[Luxury]

I had a similar problem a while back - it turned out to be sticktion in the throttle linkage. When the high idle appeared I could grab on to the linkage where it sticks out the side of the left hand carb and close it by hand. I "temporarily" fixed it by hosing down the linkage with WD-40 and planned to take the carbs out and clean them, but 6 months later still no more high idle.

Simple fix - hope it helps.

[TopCatGr58]

Not an XS11 Idol!

Hey Eddie,

I editted your thread, you had typed "IDOL" instead of "Idle"!

I reveiwed briefly several of your previous posts/thread, you had previous TCI trouble, scrubbed your Alt cover with a small spill.

But can't find much info on just what you have done to this bike, rebuilt carbs, etc.?

Sporadic idle is usually attributable an out of synch bank of carbs, or varying leaning out, happens more when bike warms up, but could also occur from vacuum leaks like around butterfly shafts, intake boots. Could also be pilot screws not adjusted out enough, or too small sized jets for bike with Indy Filters and Aftermarket pipes...both of which I don't know what yours has?!

More Info on what bike has, as well as previous work to carbs, ignition system is very helpful!
T.C.

[Eddie Gravy]

False Idol

ya i know i used the wrong word. its a geeky grammer joke.

the carbs have been fooled w/, jets, gaskets, floats. it runs great. its just random times and with in 3000 miles of riding in the past 2 weeks; its done it maybe a dozen times. at random. it just feels like when coming to a stop its still burning gas. throttles closed.

i have pod air filters and a set of 4-2 mufflers, not stock, but maybe put on in 86 or so.

[TopCatGr58]

Well,

With those mods you'll want to be sure of the jets, mains and pilots. You might even try turning the pilot screws out a 1/2 turn or so each to richen up the idle circuit to see how that affects it, 'cause it might be getting too lean once it warms up a bit?

Also your profile is a bit confusing, your signature says one of a kind SF, but your profile says 80 ??? so not sure what carbs you have on it, 78-79 series or 80-81 series? Either way, you'll probably going to want to be about 3 sizes up from STOCK on your mains, and possibly 1 size up on Pilot jets, however mine seems to work well with the OEM pilots with the screws turned out a few turns!
Good luck!

[Eddie Gravy]

the bike is an SF. and she's one year older than me.

she runs a bit rich to start with.

will fiddle with the pilot screws. but thats an every time you fire her up adjustment. this problem only happens phantomly. i can't be for sure when it will idle high.

the seats the butterflys sit in, might be a harder to get at, but more logical choice will have to take an afternoon and pull off her carbs.

[skids]

Yep, take the carbs off and get intimate. I hope that there isn't a broken pilot screw tip. I had two of those damn things stuck in the hole. I think that a hunting idle can be caused not only by a bad synch but also by a plugged mixture screw hole. I tried my best with the stick-pin method to free them, to no avail. I had to drill them. It is not normal to start rich from a cold start and lean out as it is normal temp...

Originally posted by Eddie Gravy
the bike is an SF. and she's one year older than me.

the seats the butterflys sit in, might be a harder to get at, but more logical choice will have to take an afternoon and pull off her carbs.

[GNEPIG]

.. i had this same problem on my red Special. it turned out to be the centrifical advancer was sticking. just sometimes right after a highway speed blast. after doing the timing test for this part, as stated in my clymer manual, the book said it was off. so i replaced it and it never happened again.
everyone else has some very good advice also, i wouldnt discount there ideas either
hope this helps