Carburettor Mixture Adjustment
NOTE: This topic has a wiki article associated with it. You may view it here.
DougL
Sun Aug 23, 2009 12:10 pm
El Macho
KTM Super Duke 1290, Vespa GTS 300
Joined: 27 Oct 2006
Posts: 9022
Location: Belfast Metropolitan Area
 
DougL
El Macho
KTM Super Duke 1290, Vespa GTS 300
Joined: 27 Oct 2006
Posts: 9022
Location: Belfast Metropolitan Area
Sun Aug 23, 2009 12:10 pm linkquote
Created article Carburettor Mixture Adjustment

(This message was automatically generated)
Benito
Sun Aug 23, 2009 3:09 pm
Moderator
2010 Dragon Red GTS 300 Super, 2018 Grigio Titanio Piaggio Liberty S 150
Joined: 11 Jul 2006
Posts: 16293
Location: Toronto, Canada, Fort Lauderdale, Florida
 
Benito
Moderator
2010 Dragon Red GTS 300 Super, 2018 Grigio Titanio Piaggio Liberty S 150
Joined: 11 Jul 2006
Posts: 16293
Location: Toronto, Canada, Fort Lauderdale, Florida
Sun Aug 23, 2009 3:09 pm linkquote
Nice work Doug, that will come in handy for quite a few people.
genie
Sun Aug 30, 2009 9:58 am
Gobshite Shiva
Kymco Downtown 300i the 'Dolphin Noise'
Joined: 16 Mar 2007
Posts: 14960
Location: London UK
 
genie
Gobshite Shiva
Kymco Downtown 300i the 'Dolphin Noise'
Joined: 16 Mar 2007
Posts: 14960
Location: London UK
Sun Aug 30, 2009 9:58 am linkquote
can you clarify what you mean by 'fastest possible idle'? will the idle go up to a certain point and not beyond, and any given mixture ratio?
DougL
Sun Aug 30, 2009 10:03 am
El Macho
KTM Super Duke 1290, Vespa GTS 300
Joined: 27 Oct 2006
Posts: 9022
Location: Belfast Metropolitan Area
 
DougL
El Macho
KTM Super Duke 1290, Vespa GTS 300
Joined: 27 Oct 2006
Posts: 9022
Location: Belfast Metropolitan Area
Sun Aug 30, 2009 10:03 am linkquote
genie wrote:
can you clarify what you mean by 'fastest possible idle'? will the idle go up to a certain point and not beyond, and any given mixture ratio?
Yes. When you weaken the mixture, the idle will slow. If you go too rich it will slow again. Somewhere in the middle it will be at its fastest. That's where you want it. I've added this information to the original article.
zachster
Sun Sep 20, 2009 6:41 am
Hooked
GTV 250 ie Navy Gilera Runner VXR200 Yamaha Fino Sport
Joined: 06 Sep 2009
Posts: 112
Location: all over
 
zachster
Hooked
GTV 250 ie Navy Gilera Runner VXR200 Yamaha Fino Sport
Joined: 06 Sep 2009
Posts: 112
Location: all over
Sun Sep 20, 2009 6:41 am linkquote
it mentiones that "when you turn the screw in( i presume its clockwise?) you are making it lean" but isnt turning it in clockwise killing off the air therefore making it rich?
DougL
Sun Sep 20, 2009 10:47 am
El Macho
KTM Super Duke 1290, Vespa GTS 300
Joined: 27 Oct 2006
Posts: 9022
Location: Belfast Metropolitan Area
 
DougL
El Macho
KTM Super Duke 1290, Vespa GTS 300
Joined: 27 Oct 2006
Posts: 9022
Location: Belfast Metropolitan Area
Sun Sep 20, 2009 10:47 am linkquote
It depends whether the mix screw controls the air or the fuel. On these modern Constant Vacuum carbs it controls the fuel. The more you loosen it the more fuel gets in, richening the mixture. That's counter clockwise to loosen!
zachster
Mon Sep 21, 2009 12:31 am
Hooked
GTV 250 ie Navy Gilera Runner VXR200 Yamaha Fino Sport
Joined: 06 Sep 2009
Posts: 112
Location: all over
 
zachster
Hooked
GTV 250 ie Navy Gilera Runner VXR200 Yamaha Fino Sport
Joined: 06 Sep 2009
Posts: 112
Location: all over
Mon Sep 21, 2009 12:31 am linkquote
i see...with the gt200/or the gileravxr200 (i understand them to have the same engine) is it confirmed that the a/f screw controls the fuel and not the airflow? thanks!
danny*h
Wed Sep 23, 2009 3:44 pm
Resident Gentleman
--------2008 LX150-------- Sold
Joined: 18 Jun 2008
Posts: 5045
Location: Brady, TX
 
danny*h
Resident Gentleman
--------2008 LX150-------- Sold
Joined: 18 Jun 2008
Posts: 5045
Location: Brady, TX
Wed Sep 23, 2009 3:44 pm linkquote
Updated the link for the adjusting tool.
⬆️    About 12 years elapsed between posts    ⬇️
jess
Thu Aug 26, 2021 5:38 pm
Petty Tyrant
0:7
Joined: 11 Oct 2005
Posts: 32716
Location: Bay Area, California
 
jess
Petty Tyrant
0:7
Joined: 11 Oct 2005
Posts: 32716
Location: Bay Area, California
Thu Aug 26, 2021 5:38 pm linkquote
Updated the image location of one of the images (the only one that actually resides on MV servers) and pointed at a new image of the Carb D tool at scooterwest.com.
NOTE: This topic has a wiki article associated with it. You may view it here.
  DoubleGood Vespa Design  
Post Reply
Forum -> Modern Vespa Wiki

All Content Copyright 2005-2022 by Modern Vespa. All Rights Reserved.

Modern Vespa is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to amazon.com.

Shop on Amazon Smile with Modern Vespa

[ Time: 0.0339s ][ Queries: 5 (0.0132s) ][ Debug on ][ 211 ][ Thing One ]