Jump to content

idle issue


mikev

Recommended Posts

I went for a ride today, perfect weather.  Made a couple stops, bike was running fine for about 100 miles.  Stopped at an intersection to have a quick word on the route.  No issues idling.

Drove up the road a ways didn't notice anything on the way but at the next stop light my V11 stalled when I idled.  Started right up fine, but from then on the idle is weak and it wants to stall.  Was able to ride it 20 miles back home.  Gave it a bit of an Italian tune up once or twice on the way but the problem persists.  Choke seems to help a little but maybe not as much as before on a cold start.  Changed the first 3 relays to be safe, no change.  Neutral light no longer seems to light up, not sure when in this sequence of events that might have started.  Pulled the plugs and they seem fine, just changed them last Fall.  Looked damp and smelled a bit like gas. 

Any ideas on what to check next?

 

Link to comment
Share on other sites

How many miles, you suppose?

I have never found a dealer who's tech would take the time to be absolutely meticulous with the various tune-up parameters. Of course, YMMV . . .

Otherwise, make a careful inspection of the intakes and vacuum taps to be certain something didn't come off (like a vacuum cap).

  • Like 3
Link to comment
Share on other sites

As long as the bike WAS/IS running fine, except for the idle.. there are a lot of common possibilities that at least from what I've read so far, you have not addressed.

In no particular order.

  • Fuel (different octane, different brand,etc)
  • Ambient temp, humidity.  Anything out of the "norm" since you last rode
  • Air Filters !!!!!  
  • Fuel Filters !!! (not as likely)
  • The throttle cable itself.  (this is tricky, but if it's fairly new... or really old, they can stretch that little weee bit.  There is an idle set, that may just need a pinch higher idle.
  • What is your normal idle RPM ?  
  • Air leaks..  (go around with a torque wrench, and check everything that air passes thru.  Intake, exhaust, crossover,   In fact.  If you have the torque wrench out, hit everything that has a bolt or nut.  You'll be surprised, with the amount of torque we get from two cans, it can sure rattle stuff loose.
  • Like 1
Link to comment
Share on other sites

Without wanting to denigrate Pete's no doubt valuable and accurate comment, regarding this, and only for the sake of general information because it was mentioned:

1 hour ago, Desdinova said:
  • Air leaks..  (go around with a torque wrench, and check everything that air passes thru.  Intake, exhaust, crossover, 

I've read time and again, if that is suspected as a problem, spray brake cleaner at anywhere that comes in to the question as a potential leak point with the motor idling.. If there is a leak, the idles revs will change, and one has a starting point where to look.

  • Like 1
Link to comment
Share on other sites

13 minutes ago, pete roper said:

Valve clearances are too tight. Check and set them at 4 & 6 thou inlet and exhaust. Tech probably set them to 2 & 4.

I've heard of the tight 2/4 settings, but have long thought 6/8 best? Especially in these ambient hot temps . . . :huh2:

  • Like 2
Link to comment
Share on other sites

1 hour ago, docc said:

I've heard of the tight 2/4 settings, but have long thought 6/8 best? Especially in these ambient hot temps . . . :huh2:

Funny thing with valve adjustments; there's a fine line between 'ok' and 'too tight' but a long spread of what's 'ok' on the loose side. Some race car stuff runs anywhere between .008" and .028", with guys fine tuning their throttle response and 60-foot times (drag strip stuff) with the small differences in valve timing. So the difference in felt drivability between *2-4 and *4-6 is astonishing, but the difference between *4-6 and *6-8 is probably barely noticeable. I keep mine at ~4-6. Ish. 

  • Like 1
  • Thanks 1
Link to comment
Share on other sites

Maybe this is a novice question, but what changed during my ride?  If the valves are too tight why did the bike run ok since October and then change on Sunday mid-ride?

I re-read the valve adjustment thread and feel *comfortable enough* with step 6 to check and adjust the valves.  Remove flywheel inspector, get to TDC, check the gaps.

 

Link to comment
Share on other sites

The symptom of a poor idle is typically valves too tight, if it is indeed something to do with the valves.

It could be that it was also temperature affected. The tightness of the valves may have become more of an issue when the temperature got to a certain point.

It is also possible that the valves are tightening up on their own. It is easy enough to check the valves on a Guzzi, and then you will know.

  • Like 3
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...