The air cut valve

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gltriker
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Re: The air cut valve

#16

Post by gltriker »

My natural inquisitiveness caused me to post the question above. Nothing more. But, I couldn't delete it in your topic.
Anyways
I fully understand the pilot and idle fuel circuit benefits greatly from a richer adjustment. 3 turns out from seated is my standard setting .

Now, I do have a question specific to how the extra fuel contribution by the Air Cut Valve operation when trike and I were descending a long steep mountain road 4 years ago ( White Face Mountain !) in first and second gear to save the brakes, might have possibly increased completely closed throttle , engine braking effect?
This was a question that was circulating in my head. I couldn't tell whether keeping the engine running or shutting the engine off while descending the mountain would be more effective, or is the engine braking effect equal in either of the 2 scenarios? I was too busy to keep it from leaving the road in curves to form an opinion that episode.

Keep in mind I suffered a significant brain injury 53 years ago. (hmmm. will that work? )
Yeah , I will offer that revelation up as an excuse for my inquisitive nature. ;) Thanks!
Done.
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mikenixon
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Re: The air cut valve

#17

Post by mikenixon »

The air cut system blocks ("cuts") air, it does not add fuel. And since the air cut system has no link to the throttle, it can have no effect on engine braking. Engine braking is most effective when the engine is running, yes.
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gltriker
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Re: The air cut valve

#18

Post by gltriker »

mikenixon wrote: Wed Nov 11, 2020 7:03 am The air cut system blocks ("cuts") air, it does not add fuel. And since the air cut system has no link to the throttle, it can have no effect on engine braking. Engine braking is most effective when the engine is running, yes.
Mike,
I was confident there was something of useful knowledge I could learn from you in my questions. tumb2

I doubt trike and I will ever ascend :crosso descend the 200 miles distant, White Face Mountain road again. ;)

Thank you.
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mikenixon
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Re: The air cut valve

#19

Post by mikenixon »

:)
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mikenixon
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Re: The air cut valve

#20

Post by mikenixon »

mikenixon wrote: Wed Nov 11, 2020 7:03 am The air cut system blocks ("cuts") air, it does not add fuel. And since the air cut system has no link to the throttle, it can have no effect on engine braking. Engine braking is most effective when the engine is running, yes.
Two things you might find interesting. When Honda started racing V4 roadrace bikes they found the engine configuration and higher than ever before cylinder compression added up to severe, much more than wanted, engine braking. This caused them of course to later develop their now-famous anti-back torque clutch, introduced on the 1982 production V4s. In the meantime however their solution was simply to turn the racebike engines' idle rpm way up. I mean WAY up. This greatly reduced engine braking and who cares about idle on a racebike, right? The downside was the high idle caused the engines to overheat on the starting grid, so the team mechanics were employed to stand next to the running bikes with...wait for it!...leaf blowers! To keep the not yet racing engines cool! True!

The other tech tidbit is that for a long time now Kawasaki fuel injection systems have employed programming in their computers that is there for the express purpose of managing engine braking. That is, when the computer senses the engine braking might be too much (especially for newer riders) under a given set of conditions, it moves the throttle plates to reduce it. Fact.
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77Gowing
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Re: The air cut valve

#21

Post by 77Gowing »

I am assuming, that since my 82 1100 only has half an exhaust, that I am likely going to have to go to an after market exhaust & thus should not do the air cut off defeat. That said, I am up to my gills in other issues besides motorcycles and just praying that by the time I get to this bike I remember. Plus, I'm barried in carb manutia, but its not your fault. I'm just slow to catch on. Sometimes, life gets in the way.

On the bright side, my 77 Gl is still running great.
I do love your books.
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mikenixon
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Re: The air cut valve

#22

Post by mikenixon »

:)
Pb9717
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Re: The air cut valve

#23

Post by Pb9717 »

I just rebuilt my GL1100's carbs with the Randakks kit and they work beautifully. Im doing it again for a second GL, and I may just block the air cuts in that set. BTW, 2 1/2 on the air/fuel mix screw did work perfectly....Baby purrs like a kitten.
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