Author Topic: inconsistant idle  (Read 990 times)

0 Members and 1 Guest are viewing this topic.

Offline Trav-i

  • Has finally become an
  • Expert
  • ****
  • Posts: 930
inconsistant idle
« on: July 24, 2009, 06:02:52 PM »
Hey guys I have a problem that I can't seem to figure out.  I have not had a lot of experience with running SOHC4s.  I just finally got mine running and rolling under its own power.  So here is my delima once my bike warms up its idle becomes erratic, for some reason it wants to stay around 3K on the tach.  If you snap the throttle it will idle back down, but then rise right back up. ???  What gives?  I have cleaned and rebuilt the carbs since I'm running pods I have jetted up to 120s and stock idle/slows, also running 4 straight pipes out the back.  The only thing I have not done is a sync, tried today but without some form damper our homemade gauges were useless.  I checked the intake boots there appears to be no leaks there.  However when on the road the bike has great power all the way across the board low and high.

So what have I missed.  I seem to overthink the small problems which I'm sure this is, so if anyone has got info for me I'd really appreciate it.

Thanks
Travis
Forum member #9962

I don't know a lot about anything, but I know a little about practically everthing. 

If your not first, your last - Ricky Bobby

1992 GL1500 Interstate

73 CB750 Bobber Project (Always an on going project) Sold
71 CL350 Scrambler Project (Done and riding it) Sold
78 CB750 F3 Super Sport with F 0 engine (Current project)

Offline TwoTired

  • Really Old Timer ...
  • *******
  • Posts: 21,802
Re: inconsistant idle
« Reply #1 on: July 24, 2009, 06:25:35 PM »
Carb sync
Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

Those that learn from history are doomed to repeat it by those that don't learn from history.

Offline Simpson

  • I ain't no
  • Expert
  • ****
  • Posts: 791
  • Aged to perfection
Re: inconsistant idle
« Reply #2 on: July 24, 2009, 07:27:55 PM »


If you can't fix the issue with a carb sync... then it sounds like you have the slides mixed up. Look carfeully on the bottom/top for a three digit number. A pair goes on each side because the carbs are mirrored. Good Luck! ;)
1970 CB750 K0
1975 CL/CB 360 Mix

Offline BobbyR

  • Really Old Timer ...
  • *******
  • Posts: 12,365
  • Proud Owner of the Babe Thread & Dirty Old Man
Re: inconsistant idle
« Reply #3 on: July 24, 2009, 07:58:38 PM »
You should synch those carbs for a lot of reasons. I have found that you need to set the idle speed when the bike is fully warm, using the adjustment knob. These tend to be cold blooded. If you set the idle cold with the choke out, you will always be chasing the proper idle as you ride.
Dedicated to Sgt. Howard Bruckner 1950 - 1969. KIA LONG KHANH.

But we were boys, and boys will be boys, and so they will. To us, everything was dangerous, but what of that? Had we not been made to live forever?

Offline Trav-i

  • Has finally become an
  • Expert
  • ****
  • Posts: 930
Re: inconsistant idle
« Reply #4 on: July 24, 2009, 08:00:40 PM »
I kinda thought it was a sync issue.  I just needed someone else to confirm it.

Thanks

Travis
Forum member #9962

I don't know a lot about anything, but I know a little about practically everthing. 

If your not first, your last - Ricky Bobby

1992 GL1500 Interstate

73 CB750 Bobber Project (Always an on going project) Sold
71 CL350 Scrambler Project (Done and riding it) Sold
78 CB750 F3 Super Sport with F 0 engine (Current project)