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Old 09-29-2010, 04:29 PM   #16
Max Headroom
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Quote:
Originally Posted by supershaft
I don't know about that. The air horns and velocity stacks in those square airboxes are tuned real well for midrange. There very well could be a significant difference. You are right in that since he is just getting the bike, if there is a difference he won't notice it.
I would consider the definition of "a significant difference" to imply something in the order of 20% or more. An airbox change on its own won't do that, 'cos if it did, those of us with earlier bikes would all be changing over to the later pancake filters in the quest for free horsepower. The later bikes deliver their peak power and torque at lower rpm compared to the earlier bikes, but that was in tandem with changes to compression ratio, electronic ignition, jetting and cam timing. The biggest factor with the improved midrange on the later airheads was attributed at the time to the second exhaust balance pipe IIRC.
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Old 09-29-2010, 08:50 PM   #17
Rob Farmer
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Quote:
Originally Posted by supershaft
Make your own decisions? + a Mcmillion. That is exactly why I am adding a different view on the subject.
Since it's got nothing to do with the original question Let's save this argument For another place.
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Old 09-29-2010, 09:25 PM   #18
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Quote:
Originally Posted by Rob Farmer
Since it's got nothing to do with the original question Let's save this argument For another place.
Who's arguing? We've got your experience and mine. Two different takes on the same subject. Nothing to do with the original question? What are we talking about? Airboxes?
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Old 09-29-2010, 10:04 PM   #19
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Quote:
Originally Posted by Max Headroom
I would consider the definition of "a significant difference" to imply something in the order of 20% or more. An airbox change on its own won't do that, 'cos if it did, those of us with earlier bikes would all be changing over to the later pancake filters in the quest for free horsepower. The later bikes deliver their peak power and torque at lower rpm compared to the earlier bikes, but that was in tandem with changes to compression ratio, electronic ignition, jetting and cam timing. The biggest factor with the improved midrange on the later airheads was attributed at the time to the second exhaust balance pipe IIRC.
Is that what you consider a significant difference? 20%? Or more? I thought significant meant anything of meaning or consequence? That comes in fifths for you? Slow down and take one sip at time.

Even by your high standards, an airbox change alone can do that. For instance, with my bike changing just one air horn from a small one to a large one would net you a significant drop in power at a particular rpm right around 3500. No, that isn't across the board but . . . . It isn't on a race track either.

But that couldn't be 'cos if it did, . . . . Now that's funny! On a lot of different levels. I can see a lot of airhead riders going for free but horsepower? Their bikes won't go clickity clack, leak, smoke, and shudder side to side if they get much free horsepower. Their cat skull might fly off and they would need brakes!

supershaft screwed with this post 09-29-2010 at 10:19 PM
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Old 09-29-2010, 11:42 PM   #20
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A new forum, a whole new audience...............
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Old 09-30-2010, 01:29 AM   #21
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Power schmower.

Those 80/90s airboxes are an abomination. They mark the destruction of a beautiful, comprehensive design and were BMW's first steps away from the ideal airhead. What came after were motorcycles pockmarked with compromises.

No real airhead ever had a rectangular air filter.

er, except for my '88 GS (why'd I ever trade an immaculate 78 R100S for that ugly thing?)
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Old 09-30-2010, 02:15 AM   #22
Max Headroom
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Quote:
Originally Posted by wirewrkr
A new forum, a whole new audience...............
Yep, same sh!t, different (web) address . . . I can't be bothered.
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Old 09-30-2010, 06:07 AM   #23
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I was also curious about the whole airbox thing..but towards the end it was kinda like watching THE VIEW.
Just a bunch of Kackling Hens..:)

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Old 09-30-2010, 06:54 AM   #24
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Moorespeed already has a compromise - a square air box wit a round filter on top - and he probably thinks it makes more power than the other two.

FWIW going to two large snorkels fattened up the midrange on both mY GS and my 1000 cc G/S, but I have non standard exhausts on both and my own ideas on CV carb set up.
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Old 09-30-2010, 07:02 AM   #25
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Quote:
Originally Posted by Beemerboff
Moorespeed already has a compromise - a square air box wit a round filter on top - and he probably thinks it makes more power than the other two.

FWIW going to two large snorkels fattened up the midrange on both mY GS and my 1000 cc G/S, but I have non standard exhausts on both and my own ideas on CV carb set up.
Don't mention CV ideas. they just don't understand cause gravity is different where they come from.
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Old 09-30-2010, 07:54 AM   #26
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It's about time something controversial came up.
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Old 09-30-2010, 10:26 AM   #27
supershaft
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Quote:
Originally Posted by fishkens
Power schmower.

Those 80/90s airboxes are an abomination. They mark the destruction of a beautiful, comprehensive design and were BMW's first steps away from the ideal airhead. What came after were motorcycles pockmarked with compromises.

No real airhead ever had a rectangular air filter.

er, except for my '88 GS (why'd I ever trade an immaculate 78 R100S for that ugly thing?)
That makes perfect sense to me. I don't agree with you but your reasoning holds water. If I hated the way they looked, I might think that way you do.
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Old 09-30-2010, 10:26 AM   #28
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Quote:
Originally Posted by fishkens
Power schmower.

Those 80/90s airboxes are an abomination. They mark the destruction of a beautiful, comprehensive design and were BMW's first steps away from the ideal airhead. What came after were motorcycles pockmarked with compromises.

No real airhead ever had a rectangular air filter.

er, except for my '88 GS (why'd I ever trade an immaculate 78 R100S for that ugly thing?)
That makes perfect sense to me. I don't agree with you but your reasoning holds water. If I hated the way they looked, I might think the way you do.
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Old 09-30-2010, 10:44 AM   #29
supershaft
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Quote:
Originally Posted by Beemerboff
Moorespeed already has a compromise - a square air box wit a round filter on top - and he probably thinks it makes more power than the other two.

FWIW going to two large snorkels fattened up the midrange on both mY GS and my 1000 cc G/S, but I have non standard exhausts on both and my own ideas on CV carb set up.
I am not doubting you. The whole setup is dependent on so many variables. I have tried going to two large air horns on a handful of different bikes. Most of them had non-stock mufflers and jetted Bing CV's. I tried it on one of my own bikes from stock including Bing CV's to fairly modified including 38mm Dellorto's. It always had the same effect in putting a BIG hole in the midrange. I am sure at least some of it can be reduced through differing setup but I have never tried it. What is working for you jetting wise?
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Old 10-02-2010, 03:34 PM   #30
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Quote:
Originally Posted by supershaft
I am not doubting you. The whole setup is dependent on so many variables. I have tried going to two large air horns on a handful of different bikes. Most of them had non-stock mufflers and jetted Bing CV's. I tried it on one of my own bikes from stock including Bing CV's to fairly modified including 38mm Dellorto's. It always had the same effect in putting a BIG hole in the midrange. I am sure at least some of it can be reduced through differing setup but I have never tried it. What is working for you jetting wise?

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