4 air filters directly onto carbs?NC29
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4 air filters directly onto carbs?NC29
hi my old man has just suggested sticking 4 K&N air filters directly onto the carbs and doing away with the airbox, can anyone give me any suggestions? advantages? things to look out for or whether to just blatently ignore my dad and stick one K&N in the box? or just stick a normal filter in?
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Re: 4 air filters directly onto carbs?NC29
Hahaha
Good luck setting up the jetting with pods and the only advantage to fitting a K&N is its reusable you won't see any power gain even with dyno set up 29s just dont like them.
Good luck setting up the jetting with pods and the only advantage to fitting a K&N is its reusable you won't see any power gain even with dyno set up 29s just dont like them.
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Re: 4 air filters directly onto carbs?NC29
I would have thought the airbox is all to do with air flow, pressure waves, resonance, air momentum etc etc.
The Honda dudes are very clever! You take that airbox away and you better have some serious kit in your shed to sort it all out.
Heres a simple question - why are the 4 inlet ports not all equal lengths?
Read this.............
http://en.wikipedia.org/wiki/Helmholtz_resonance
The Honda dudes are very clever! You take that airbox away and you better have some serious kit in your shed to sort it all out.
Heres a simple question - why are the 4 inlet ports not all equal lengths?
Read this.............
http://en.wikipedia.org/wiki/Helmholtz_resonance
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Re: 4 air filters directly onto carbs?NC29
Good luck .. when you sort it out --- tell all how its done !!
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Re: 4 air filters directly onto carbs?NC29
Do you mean like this?

These are for flatslides though...
These are for flatslides though...
Skint Novice F400
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Re: 4 air filters directly onto carbs?NC29
you mean the inlet 'trumpets'?gullarm wrote:
Heres a simple question - why are the 4 inlet ports not all equal lengths?
they are equal lengths on the later bikes and in the kit parts
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Re: 4 air filters directly onto carbs?NC29
My point is that the Honda dudes do things for a reason, you start playing around and unless you have the back up ( as in endless dyno runs ) to check what you are doing how do you know its any better.tanuki wrote:you mean the inlet 'trumpets'?gullarm wrote:
Heres a simple question - why are the 4 inlet ports not all equal lengths?
they are equal lengths on the later bikes and in the kit parts
And how much do the 4 filters cost?
Carbs are something I wouldn't play with.
Look at the discussion about low running below 3000rpm. viewtopic.php?f=28&t=37686
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Re: 4 air filters directly onto carbs?NC29
I'll just stick a K&N filter in the box then 

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Re: 4 air filters directly onto carbs?NC29
I am doing away with the air box on the 400/600 fighter... Yes plenty of set up will be needed...
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Re: 4 air filters directly onto carbs?NC29
I've done a few of these NC23 Tri Arm - 4/6 conversions.
What I did was carefully panel beat the underside of the Original Tri Arm tank (not easy but being an old Race Car body restorer I have the tools / skills) - this then allows the fitment on a KN air filter in the 600 air box base ....
I also seen it done the easy way by simply lifting the tank but it looks crap and you have big issues with the fuel tap hitting the chassis.
Way way easier to set up then ....
Have a try .... hope that helps.
Graeme
What I did was carefully panel beat the underside of the Original Tri Arm tank (not easy but being an old Race Car body restorer I have the tools / skills) - this then allows the fitment on a KN air filter in the 600 air box base ....
I also seen it done the easy way by simply lifting the tank but it looks crap and you have big issues with the fuel tap hitting the chassis.
Way way easier to set up then ....
Have a try .... hope that helps.
Graeme