Low speed idle on VS1400

[Canuck1400]

Hi all,

I have a 1988 VS1400 and seem to have a problem with the low speed idling. When the bike is just sitting it idles fine, but as I am riding and down shifting the engine stalls(very dangerous). This stalling can also be done by hitting the throttle very hard at a stand still.

Is there a carb adjustment besides the idle adjustment that can cause this?

Thanks for any responses.

[Clint]

Sounds like your high-speed jetting is off. You might be lean in the main circuit or have a blockage. Is it stock?

[Canuck1400]

Thanks for the info Rowdy,
Yes the bike is stock, but I think the jets have been worked on. Is there an adjustment for the jets?
I also think maybe the carbs are lean.

[Clint]

We'll need to wait for someone with more experience on this. I've worked on very few carbs and only have a general understanding of common problems.

[DrBob]

Run some carb cleaner in the next tank of gas. Can't hurt.
The idle adjuster is on the rear carb. It is a brass colored thumb screw sticking down- give it a quarter turn while the engine is running, goose the throttle, and let the motor come back down to idle. Repeat until the bike is idling smoothly without racing.

Here is a thought: when was the last time the clutch fluid was changed? If the fluid is more than a year or so old, gunk and condensation build up in it, and tiny air bubbles form when the fluid heats up from the bike running and the clutch being used. This will cause the clutch to drag, making the engine want to stall when it is hot. Look in the window on the clutch side master cylinder. If the fluid is dark or cloudy, change it. It should be nice and clear.

When was the last time your air filters were changed? A clogged filter can cause all kinds of problems.

Ok, now that we have tried the easy things, check out the carbs. Do you see the caps still on the pilot screws at the bottom of the carbs? They should be smooth and pressed into the pilot screw hole. If you can see the philips head pilot screw, then the caps have been drilled off and someone has played with the mixture. If the bike has, or ever had, aftermarket pipes or holes drilled in the stock baffles, then the mixture was adjusted and the jets may have been changed. Turn the pilot screws all the way in, then back them out 2 1/2 turns. Play with then a quarter turn at a time until the bike runs well again.

[Trapper]

Welcome back DrBob, hope you had a good birthday.

[DrBob]

Thanks man! I had a great birthday, riding up in the mountains with 17 great friends who came from all over Georgia, Alabama, South Carolina, and even Texas to celebrate with me. Hopw cool is that?

It has been a wild summer, with many, many out of state trips, lots of working, and some writting. I'll post on the main board and tell folks about my adventures once I have time to write them down.