Motor running away at start

[patastinky]

When i kick start the bike it revs to the max. I have to use the OFF/RUN/OFF button to stop the engine from redlining. All my air and gas screws on the carbs are turned tight inward. 1975 RD350 stock

[Striker1423]

Vacuum tubes?

[rodneya]

What bike is it?
By gas screw do you mean the idle screw? If that is screwed right in it will rev on startup.
Set airscrew at 1.5 turns out and idle screw so that it is just touching but not lifting the slide.
If they are vacuum tubes?? you need to block them off

[m in sc]

do you mean oil injection lines or breather tubes? theres no 'vacuum lines' on rd carbs.

[85RZwade]

Is this your '75 RD350?

[m in sc]

also make sure the slides aren't hanging up in the carbs for any reason. .02

[pidjones]

What bike is it?
>>>>>>>>>>>>>By gas screw do you mean the idle screw? If that is screwed right in it will rev on startup.<<<<<<<<<<<<<
Set airscrew at 1.5 turns out and idle screw so that it is just touching but not lifting the slide.
If they are vacuum tubes?? you need to block them off

This.

[patastinky]

Vacuum tubes?

Oops. I don't know what I was thinking.

What bike is it?
By gas screw do you mean the idle screw? If that is screwed right in it will rev on startup.
Set airscrew at 1.5 turns out and idle screw so that it is just touching but not lifting the slide.
If they are vacuum tubes?? you need to block them off

1975 RD350

What bike is it?
By gas screw do you mean the idle screw? If that is screwed right in it will rev on startup.
Set airscrew at 1.5 turns out and idle screw so that it is just touching but not lifting the slide.
If they are vacuum tubes?? you need to block them off

Yes, Idle screw and the air screw on the carbs. I have mine turned all the way in. I thought that would be a good starting point.  I'll try what you said tomorrow. Disregard the vacuum tube comment. :)

also make sure the slides aren't hanging up in the carbs for any reason. .02

Slides aren't hanging up. They don't go all the way down, but aren't they supposed to have like a crescent moon shape at when they are down (off throttle)?

[NYSingh]

Crossover tube connected?

Can you post photos/videos of how your carbs are set up?

[Djg8493]

Are you running oil pump or Pre-mix?  If Premix are the oil pump tubes in the carbs blocked off?

[m in sc]

the front (motor side) of the slide should be able to hit bottom.


when the slide screw just touches, go in 1-1.5 turns and should be a good starting point. 

airscrew starting point 1.25-1.5 turns out

[Striker1423]

^^^ What mark said.

[pdxjim]

Print this out for bathroom and before bed reading.

http://www.mikuni.com/pdf/vmmanual.pdf

[patastinky]

Crossover tube connected?

Can you post photos/videos of how your carbs are set up?

yes, they are connected. Sure thing, I'll take a video :)

Print this out for bathroom and before bed reading.

http://www.mikuni.com/pdf/vmmanual.pdf

This is awesome, thank you. Already started reading it.

the front (motor side) of the slide should be able to hit bottom.


when the slide screw just touches, go in 1-1.5 turns and should be a good starting point. 

airscrew starting point 1.25-1.5 turns out

is the "slide screw" the "idle screw"? and by "just touches" do you mean while "remove the screw, begin to screw it in and as soon as a thread catches, turn 1 full or 1.5 turns.

[SoCal250]

is the "slide screw" the "idle screw"? and by "just touches" do you mean while "remove the screw, begin to screw it in and as soon as a thread catches, turn 1 full or 1.5 turns.

Yes by "slide screw" he's referring to the idle screw. Thread each screw in until the pointed tip just contacts the slide, then turn 1 to 1.5 additional rotations. If you're looking into the bellmouth of the carb you will be able to see the slide slowly rising in the bore very slightly as you turn the screw in.