Bike won't idle

badbilly · 07-09-2005, 10:26 PM

Dear Boxer-philes,

Mr. B Cup has been behaving wonderusly--until last Monday, when it lost the ability to idle without using the handlebar fast-idle thing.

What gives? I'm so pathetic...I don't even know how to adjust its idle. OTOH, this bikes been so good, I haven't had to. In any event, its still on warranty if it need parts etc.

And I rented a Goldwing for an afternoon. It was fun for cruising on the highway, but it got a tad warm behind all those cylinders(temp was 112). I believe I'll be keeping the bmer.

Later, BB

foobeemer · 07-10-2005, 05:02 AM

Uh-oh....handlebar fast idle thing??? That choke should only be used to start a cold bike, then immediately shut off. Even a cold bike will hold a rough idle without that choke on once she starts. Running with that choke on is going to foul the plugs from too rich a mixture after awhile which can add to the your problems you started out with. My advice is to give that bike up to the shop and have it diagnosed there. The best thing you can do is answer any tech's questions truthfully about the bike's behavior to help them decide where to start looking. If you start playing around with carb settings you are gonna compund the problem and make it harder for a tech to unscramble-besides you want to be able to ride that bike to the shop to save on any hauling or pickup charges you are going to incur once you scramble the carb mixtures and completely disable it! What's the bike's history? Could you have gotten a bad tank of gas? Did this problem start while you were riding or at startup one day out of the blue? Roger????

brad black · 07-10-2005, 05:16 AM

the thing on the handlebars is just a fast idle. no enrichment.

does it otherwise run as before?

Jeff Williams · 07-10-2005, 10:22 AM

Rick,
get your bike fixed and we'll go riding again.
Hope life is being good to you,(other than the gold wing thing)
cya
jeff

ps memories jw

Dr. Curve · 07-10-2005, 04:46 PM

Fouling one plug on a 4 plug bike can cause a slight drop in idle even though butter fly adjustments have not been changed. Check plugs, especially the bottom ones, on a 4 plug bike if you have been running extended times with the enrichment circuit activated. Best,

1100s nut · 07-10-2005, 05:10 PM

One quick/simple to check. Where the throttle come into the throttle bodies check to see if they are both seated. A couple of years ago I had on come out of its little cup/seat and would not run. Also would you let us know what the problem was when you get it fixed.

Good luck!
Lane

Dr. Curve · 07-10-2005, 05:57 PM

Good point Lane, to some extent. Generally if cables are too tight then the idle increases on that bank or cylinder........while if cables are properly adjusted or "too loose" then the idle reverts back to proper idle. All else being equal. Still, its possible that a air screw got "thumbed" (as we once called it in the old days) by someone passing by. In that case its misadjusted and easy fix. If, however the cable, which has now stretched loose, was engageing before the butterfly stop screw on that TB, and had been used to control the idle speed (instead of the stop screw).......then a rough idle would start to appear as the cable stretched normally but still without enguaging the offending TB stop screw final to its stop shoulder. In this case a rough idle will occur. Most likely something simple like a air screw or cable stretch but sometimes things like plugs or default circuit can be harder to find.

ExarKunONe · 07-10-2005, 10:07 PM

will it idle after it warms up?

nucleus · 07-11-2005, 04:51 AM

brad black wrote - "the thing on the handlebars is just a fast idle. no enrichment";

Dr Curve wrote -
"Check plugs, especially the bottom ones, on a 4 plug bike if you have been running extended times with the enrichment circuit activated".

When touring the Pyrenees I used the 'fast idle' on uphill hairpin sections as it tends to smooth the on/off throttle transition.
Was I running rich and risking plug fouling or not?

Also, is the idle adjustment simple or a shop job (mine's been a bit slow @ 1000rpm since the last service).

Cheers,
Graham

ExarKunONe · 07-11-2005, 02:23 PM

it shouldnt harm your plugs. It would be the same as holding the throttle open a little.

bikerfish1100 · 07-11-2005, 11:04 PM

Idle is simple to adjust, if you have a TwinMax. if no T-Max, you're likely to leave the TBs out of sync, and that is not good.
and on any fuel injected BMW, the fast idle adjustment is just that- a fast idle adjustment. it raises the idle speed. it is not an enrichment device like a choke on a carbuerated machine- the fuel injection computer takes care of setting and regulating the fuel mix.

ErricZ · 07-12-2005, 02:50 PM

A joke I heard from a dealer (or maybe just a persnickity BMW geezer) was to pop one of the throttle cables out of the plastic end and let it rest on the metal adjuster, giving a waaaay off-balance throttle.