Results 1 to 2 of 2
  1. #1
    CB750 New Member hdean2019's Avatar
    Join Date
    Aug 2019
    Location
    Charlottesville, Va
    Posts
    1

    Exclamation First Bike, CB750 Custom, carb issues. Need some help/advice

    I recently bought a 1980 CB750C. Ive been driving it daily for about a month and I'm having several issues with the carburetors. For starters, the bike idles very poorly. In first and second gear the acceleration is uneven and sometimes jerky but it drives completely fine at higher speeds. It also leaks fuel out of the overflow tubes every single time I ride it. I had the carbs cleaned last week and it hasn't helped at all. I still have the original air box on it. Any advise or suggestions? I'm not sure what to do and I don't want to sink a ton of many into figuring this out before even fixing it. Thanks in advance.

  2. #2
    CB750 Guru amc49's Avatar
    Join Date
    Sep 2015
    Location
    Fort Worth TX.
    Posts
    2,667
    If they use ethanol in your local fuel then likely a lot of the flooding, rust in tank messing up the carb needles. Ethanol + older bikes = fits.

    Most owners never set the valves ever and that makes them utterly run like crap. A compression test to see how bad yours is. No knowledge of that sends most to the carbs and often in error, although they CAN be a big issue.

Similar Threads

  1. Make Offer - 1981 CB750 Custom...Most of a bike..FREE
    By hcritz in forum Classifieds
    Replies: 0
    Last Post: 02-04-2019, 08:55 PM
  2. 1982 CB750 Custom First Bike project
    By Jgaray in forum Builds
    Replies: 6
    Last Post: 05-06-2017, 01:51 AM
  3. Need Help 1981 Cb750 carb issues
    By DangerZoneNYC in forum Carburetors / Fuel
    Replies: 4
    Last Post: 03-31-2017, 06:24 PM
  4. 74 cb750 /speed moto carb issues
    By DildoMagic104 in forum Carburetors / Fuel
    Replies: 3
    Last Post: 04-22-2016, 06:57 PM
  5. CB_Projects 1980 CB750 Custom Rat Bike
    By CB_Projects in forum The DOHC Garage (1979-1983)
    Replies: 1
    Last Post: 11-14-2015, 01:09 AM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •