81 Suzuki GS650GL only runs on full choke

air filter blocked, needs changing

You just need to have the carb cleaned and rebuilt, you have some build up inside and the jets are starting to clog

If is runs better with full choke, then the bike is lean, check for air leaks at the carb manifold, vacumn cracked hoses, non standard exhausts, perhaps the mufflers have rusted out while sitting

Yes, cleaning the carbs is needed. The main jets are plugged up. Standard factory settings for the air and pilot screws are one and one-half turns outward from a lightly seated position.

Ride the bike 20 or so miles on open road. Stop and remove plug to inspect. 'Are they black or white ?


Black =rich white=lean

The carbs are gummed up with varnish from sitting so long. Clean the carbs.

it seems the bike is not getting enough fuel if the choke needs to be on check fuel tap or any in line filters

The pilot jets are still gummed up. This jet controls the idle port and usually gets overlooked. To clean it the jet must be removed along and the adjusting screw as well. The circuit must be cleared of gum. For each individual carb, when removing the jet and the adjuster, count the turns then remount that number of turns. Now turn the adjuster screw 1/4 turn counter clockwise.

I am having a similiar problem. bmw r 1100 s will only start with full choke and will die if I cut off choke or give it any throttle. This is my first bike and it has been sitting in a garage for 2 years. I took out the carbs, cleaned them and rebuilt them. I didn't find any residual in the carbs and they were very clean. Today, I was able to get the bike running and took it down the neighborhood but after the bike warms up it idles at 6K! Man... If I can't find any answers from this forum, I will probably drop it off at the motorcycle shop just down the hill from me. Any suggestions anyone? I think I will try to drain the fuel and give it new gas. But still....