Skip to content
View in the app

A better way to browse. Learn more.

Trials Central

A full-screen app on your home screen with push notifications, badges and more.

To install this app on iOS and iPadOS
  1. Tap the Share icon in Safari
  2. Scroll the menu and tap Add to Home Screen.
  3. Tap Add in the top-right corner.
To install this app on Android
  1. Tap the 3-dot menu (⋮) in the top-right corner of the browser.
  2. Tap Add to Home screen or Install app.
  3. Confirm by tapping Install.

Mikuni Carb

Featured Replies

hey all,

on a mikuni carb which way do you turn the mixture screw to make it leaner?

thanks

Jack H

I disagree, I believe that for making it leaner you need to turn it out (i.e. anti-clockwise).

Which side of the carb is the screw on? Nearer to the airbox or the engine?

If airbox, unscrewing = more air (leaner)

If engine, unscrewing = more petrol (richer)

*DISCLAIMER*

The above might be utter b*****ks, as I can't remember either ;)

Well as an ex M/C mechanic it was always out for leaner and in for richer(shutting off the air) never the other way round. 3 x City and guilds in the subject. But as I tell folk I have forgot more than I ever knew. ;)

Out is leaner on the Mikuni VM carbs. The mixture screw on the mikuni is in the air circuit.

Out is richer on the Del Orto because the mixture screw on the Del Orto is in the fuel circuit.

Dan

Which side of the carb is the screw on? Nearer to the airbox or the engine?

If airbox, unscrewing = more air (leaner)

If engine, unscrewing = more petrol (richer)

*DISCLAIMER*

The above might be utter b*****ks, as I can't remember either ;)

In my experience Mr Kinell is right.

You can check by going to both extremes, you should be able to tell if its too rich or weak

Hi Jack_H,

Kinell is correct!

If the mixture screw is between the carburetor slide and the airbox, the screw controls the amount of air and should be turned outwards, anti-clockwise to lean the mixture.

If the mixture screw is between the carburetor slide and the engine, the screw controls the amount or fuel and should be turned inwards, clockwise to lean the mixture.

Link below for Mikuni manual. The graph on page 10 shows that as the mixture screw (air screw) opens,the flow of fuel decreases, therefore the mixture becomes weaker....alegedly! :wall:

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

....oops! Meant to say the flow of air increases! :thumbup:

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

Account

Navigation

Search

Search

Configure browser push notifications

Chrome (Android)
  1. Tap the lock icon next to the address bar.
  2. Tap Permissions → Notifications.
  3. Adjust your preference.
Chrome (Desktop)
  1. Click the padlock icon in the address bar.
  2. Select Site settings.
  3. Find Notifications and adjust your preference.