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It does appear that the carbs themselves are the most restrictive part of the intake system. But if you take an emissions analyzer, and get a reading with the whole system intact, then remove the ducts from the carbs, run it with no filters at all, you will get a leaner reading. If you want to go further, it actually looks like the valves are the most restrictive part with stock cams. But that's not what the analyzer says. It's a little more complicated than the actual size of various openings. You also have to take air velocity into account.

On the duct installation thing, I tried the stuffing them in past where they were supposed to be, with the idea of pulling them back out, but just couldn't get my hands in there to do it. They just wouldn't bend enough on the top end. The only option was to remove both air filter housings and the cooling system parts like the manual says. And since I figured I would be removing the carbs again (I've done it twice already since modifying the ducts) I decided to try and find a way to make it easier.
 

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It does appear that the carbs themselves are the most restrictive part of the intake system. But if you take an emissions analyzer, and get a reading with the whole system intact, then remove the ducts from the carbs, run it with no filters at all, you will get a leaner reading. If you want to go further, it actually looks like the valves are the most restrictive part with stock cams. But that's not what the analyzer says. It's a little more complicated than the actual size of various openings. You also have to take air velocity into account.
I don't buy a bit of this. I was involved with your post until the part where some kind of analyzer told you the valves were not the restriction.

Justification of your position?

Even though I prefer to tune street with a narrow band, I have owned a wide band w/data logging for 10 years. I have been asked to be involved with the tune up on 4 M/C and a handful of street cars this year. I will only 'help' competent mechanics.

You and I would have an argument and maybe a bet if I cared more than I do.
 

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Discussion Starter #24
I was involved with your post until the part where some kind of analyzer told you the valves were not the restriction.

Justification of your position?
I had a similar question. Hypothetical answer: A flow bench?
 

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Discussion Starter #26
I didn't have any seat time to make a comparison, had only ridden a mile before tearing into the work ... stator, dampers, earshave, and coasters. Also tires and spline lube.

Everything I read here said the earshave improves performance. It does run great, I know that.

If I ever have to pull the carbs, it will be a lot easier. It's also nice to have all that plumbing gone.
 

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Discussion Starter #28
It's really not that much work. Like I said before, it takes more to write it up than to actually do the jobs.

After you get the plumbing and airbox out, slap on the filters and coasters, then hook up the harness.
 

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Hi Spock, read your job on removing the air box,so I reversed the procedure and refitted the air box. It gave me a little trouble getting the spouts on the front of the air box, over the front rocker,so I shortened them a tadd. During the process I discovered, the smaller of the two,when cut, opened up to a much larger diameter. So I saved the off cut, for the purpose of refitting in the carby breather line. My presumption is, that the engineer that designed the thing calibrated the size to let the carburettors breath as opposed to being vacuumed. Alternately, I may just run an accessory breather filter, and cap the old one. I never though that air box would ever go back in, good tip Spock. Thanks.
I must have pushed the wrong button the reply was to Spocks air box removal. OOPS!
 

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Linkmeister Supreme
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I just stuck this thread in the carbs and fuel forum.
(I don't think stickyed is a real word. lol ;))
 

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FREEBIRDS MC CENTRAL NY
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Eww now its all sticky;)
 

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Expendable newbie
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Pour some rubbing alcohol on it, maybe you can get the stickiness off.
 

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FREEBIRDS MC CENTRAL NY
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But it burns.it burns
 

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Expendable newbie
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Maybe the best thing here is to put you out of your misery.
 

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FREEBIRDS MC CENTRAL NY
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16,076 Posts

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Expendable newbie
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What's with you and burning. (Disappointingly shaking my head)

Hey guess what buddy, I have a present for you out back. It's behind the barn.
 

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FREEBIRDS MC CENTRAL NY
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Fire makes the food taste better. Yeah let's go behind the barn.we'll burn that down.we'll have fried chicken and steak
 

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That's going to be one big fire. Anybody else wants fired chicken or steak?
 

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FREEBIRDS MC CENTRAL NY
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Country fired chicken ;)
 

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Chasin' the blacktop
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Chicken house a friend owned with 12,000 pullets (young hens for you city folk) burned last month.... We ate good for over a week!
 
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