Idle Mixture Screw Adjusment
- Limey01
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Idle Mixture Screw Adjusment
Better to remain silent and be thought a fool than to speak out and remove all doubt.
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Re: Idle Mixture Screw Adjusment
What setting does everyone run there fuel/mixture screws at please.
- jt
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Re: Idle Mixture Screw Adjusment
Cannot see what it is, can you provide a direct link ?
JT In Texas
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The biggest troublemaker you'll probably ever
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Re: Idle Mixture Screw Adjusment
You will have various responses. However, I'd suggest between 1 1/2 and 1 3/4. Don't go beyond 2.tonybusa1300r wrote: βThu Apr 30, 2020 1:15 pmWhat setting does everyone run there fuel/mixture screws at please.
Larry Zimmer
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Re: Idle Mixture Screw Adjusment
Over the years, various guys have tried (including me) settings from 2 - 3 turns out. I've long ago settled on two turns out max. I've had the opportunity to rebuild several sets of carbs over the years that I know for sure have never been touched from the factory. When I get such a set, a rarity these days, I always check how many turn open the pilot screws are. I've never found one over 1 1/2 turns open. Most are about 1 turn. This is how Honda would supposedly set them according to the procedure in the manual - using a high resolution tachometer and find the highest engine idle for each cylinder. This is why no two are exactly the same using Honda's procedure. I don't know anyone that actually does this. I bench sync the throttle bodies, set the mixture screws 2 turns out and gauge sync them if I have the whole bike here and can run it. Absolute perfection could be had using Honda's procedure, but you need a very precise tachometer.
- NobleHops
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Re: Idle Mixture Screw Adjusment
We have been using a tool called a Gunson "Colortune", as a final step in tuning carburetors after we restore a bike after rebuilding carburetors, adjusting valves, etc. Opinions clearly vary on the merits of this tool, but I will say based upon our first-hand experience that the bikes start instantly, carburate crisply, and the plug insulators look light tan with little or no deposits on the electrodes. YMMVdaves79x wrote: βSat May 02, 2020 7:20 amOver the years, various guys have tried (including me) settings from 2 - 3 turns out. I've long ago settled on two turns out max. I've had the opportunity to rebuild several sets of carbs over the years that I know for sure have never been touched from the factory. When I get such a set, a rarity these days, I always check how many turn open the pilot screws are. I've never found one over 1 1/2 turns open. Most are about 1 turn. This is how Honda would supposedly set them according to the procedure in the manual - using a high resolution tachometer and find the highest engine idle for each cylinder. This is why no two are exactly the same using Honda's procedure. I don't know anyone that actually does this. I bench sync the throttle bodies, set the mixture screws 2 turns out and gauge sync them if I have the whole bike here and can run it. Absolute perfection could be had using Honda's procedure, but you need a very precise tachometer.
N.
Nils Menten
Tucson, Arizona, USA
'82 CBX, among others.
Tucson, Arizona, USA
'82 CBX, among others.
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Re: Idle Mixture Screw Adjusment
Bought what ? Link did not work for me either. Can you post Walmart link ?
1979 CBX (faster Red)
1981 CBX Streetfighter
2017 Aprilia Tuono.
Past rides : FZ1, BMWS100rr,S1000r,k1300S,YAMA RD350,Enfield 350
1981 CBX Streetfighter
2017 Aprilia Tuono.
Past rides : FZ1, BMWS100rr,S1000r,k1300S,YAMA RD350,Enfield 350
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Re: Idle Mixture Screw Adjusment
ALL: Apologies for the problem with the gallery photos. Unfortunately, the new software is having a hiccup recognizing the gallery. (Had to do it. Old software was being eliminated.) Meanwhile, if you can, when posting try to include photos in the post.
Larry Zimmer
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Re: Idle Mixture Screw Adjusment
Did not see a picture or part number for the mixture screw adjustment tool at Walmart.
Bud
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Re: Idle Mixture Screw Adjusment
when using your color tune, how many turns out on the air/mix pilot screws do you find on averageNobleHops wrote: βSun May 03, 2020 12:36 pmWe have been using a tool called a Gunson "Colortune", as a final step in tuning carburetors after we restore a bike after rebuilding carburetors, adjusting valves, etc. Opinions clearly vary on the merits of this tool, but I will say based upon our first-hand experience that the bikes start instantly, carburate crisply, and the plug insulators look light tan with little or no deposits on the electrodes. YMMVdaves79x wrote: βSat May 02, 2020 7:20 amOver the years, various guys have tried (including me) settings from 2 - 3 turns out. I've long ago settled on two turns out max. I've had the opportunity to rebuild several sets of carbs over the years that I know for sure have never been touched from the factory. When I get such a set, a rarity these days, I always check how many turn open the pilot screws are. I've never found one over 1 1/2 turns open. Most are about 1 turn. This is how Honda would supposedly set them according to the procedure in the manual - using a high resolution tachometer and find the highest engine idle for each cylinder. This is why no two are exactly the same using Honda's procedure. I don't know anyone that actually does this. I bench sync the throttle bodies, set the mixture screws 2 turns out and gauge sync them if I have the whole bike here and can run it. Absolute perfection could be had using Honda's procedure, but you need a very precise tachometer.
N.
ICOA # 6786
Retired, now my job is restoring old hondas!
Bike in the garage right now:
1979 CBX1000 red
1980 CBX1000 red
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1975 gl1000 red
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1977 gl1000 blue
1977 gl1000 black
1978 cb750f super sport
1979 cb750f super sport
Retired, now my job is restoring old hondas!
Bike in the garage right now:
1979 CBX1000 red
1980 CBX1000 red
1981 CBX1000 prolink
1975 gl1000 blue
1975 gl1000 red
1975 gl1000 sulfur yellow
1975 gl1000 red
1976 gl1000 sulfur yellow
1977 gl1000 black
1977 gl1000 blue
1977 gl1000 black
1978 cb750f super sport
1979 cb750f super sport
- NobleHops
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Re: Idle Mixture Screw Adjusment
JoeInTuc will have to answer that, but if I remember correctly, we end up around 2.
Nils Menten
Tucson, Arizona, USA
'82 CBX, among others.
Tucson, Arizona, USA
'82 CBX, among others.
- NobleHops
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Re: Idle Mixture Screw Adjusment
Joe confirms that we start at 2 turns before using the Colortune, generally dial them in +- 1/4 turn from there. Sometimes as much as 1/2 turn.
Nils Menten
Tucson, Arizona, USA
'82 CBX, among others.
Tucson, Arizona, USA
'82 CBX, among others.