Author Topic: What UNI air filter to attach directly to carb?  (Read 4088 times)

leeleatherwood

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What UNI air filter to attach directly to carb?
« on: March 30, 2013, 05:58:33 PM »
What UNI filter to I need that attached directly to the carb?

Its a Mikuni carb if that matters.

Thanks!

LiveWire

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Re: What UNI air filter to attach directly to carb?
« Reply #1 on: March 31, 2013, 05:26:44 PM »
Is the air box missing?

leeleatherwood

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Re: What UNI air filter to attach directly to carb?
« Reply #2 on: April 01, 2013, 08:00:44 AM »

nevadanotch

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Re: What UNI air filter to attach directly to carb?
« Reply #3 on: April 02, 2013, 08:23:24 AM »
You do not want to put just an air cleaner on the end of the carb without supporting it somehow.

Get yourself an airbox or a proper way to support the filter system.  All that vibration is not good for the carb or the rubber intake boot.
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leeleatherwood

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Re: What UNI air filter to attach directly to carb?
« Reply #4 on: April 13, 2013, 10:09:06 AM »
So, any word on this?

I am not paying that much for a stock airbox setup.

I can find a way to support the foam air filter if needed.

odypilots

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Re: What UNI air filter to attach directly to carb?
« Reply #5 on: April 13, 2013, 02:07:23 PM »
Since it's not a stock carb, you'll need to measure the size of the air filter end of your carb, then find some place to order a Uni, either on line or a enginecycle shop. I use a 2 1/2" ID X 6" HGT 2 stage Pod by Uni on my Mukuni carbs. Part Number UP-6245AST.
The usual 'my two cents' disclaimer applies. :)

leeleatherwood

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Re: What UNI air filter to attach directly to carb?
« Reply #6 on: April 13, 2013, 05:21:07 PM »
thanks odypilots!

odypilots

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Re: What UNI air filter to attach directly to carb?
« Reply #7 on: April 13, 2013, 07:10:30 PM »
You're welcome. :)
The usual 'my two cents' disclaimer applies. :)

Athis

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Re: What UNI air filter to attach directly to carb?
« Reply #8 on: April 14, 2013, 07:43:33 PM »
Along this line of subject perhaps the more experienced members can help clear something I've been wondering.

So, if the air box is replaced with just a stand-alone uni type filter, does the carb need to be re-jetted?

odypilots

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Re: What UNI air filter to attach directly to carb?
« Reply #9 on: April 15, 2013, 04:03:33 AM »
Along this line of subject perhaps the more experienced members can help clear something I've been wondering.

So, if the air box is replaced with just a stand-alone uni type filter, does the carb need to be re-jetted?

Yes.
The usual 'my two cents' disclaimer applies. :)

Athis

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Re: What UNI air filter to attach directly to carb?
« Reply #10 on: April 15, 2013, 06:15:48 AM »
Ok,

As I understand the purpose of the box is primarily to protect the filter from a barrage of dirt/water as well as providing non-disturbed air, like a plenum of sorts.

So is it safe to say that the Ody from factory was designed to work with a certain amount of vacuum in the box? And if so, what would the purpose of that be?
Shouldn't the engine/carb breath as much as is needs to?

Having said that, I noticed lot's of folks modify the box to get more air into the carb. Is this because the simply want more power, or is it because of the vacuum restriction that perhaps was a design mistake?

odypilots

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Re: What UNI air filter to attach directly to carb?
« Reply #11 on: April 15, 2013, 07:33:22 AM »
I would call it a design decision. Honda wasn't after maximum power, so some choose to go after that. My opinion is the vacuum is more a byproduct of a air box than a design goal.
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Athis

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Re: What UNI air filter to attach directly to carb?
« Reply #12 on: April 15, 2013, 09:15:00 AM »
Very interesting. Thanks for the reply Odypilots. :)

LiveWire

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Re: What UNI air filter to attach directly to carb?
« Reply #13 on: April 15, 2013, 03:08:14 PM »
I would roughly estimate the amount of dirt exposure to a filter attached directly to the carb is about 10 times that of being in the air box with the snorkel. Adding a second hose does not seem to contribute much if any more dirt while allowing the air flow of an open element.

My Formula Cross which has open elements currently needs a complete rebuild due to sucking dirt through the filter. The filters were already dirty then got wet. The dirt got washed through the filter. Building a good air box setup is not not that easy or I would have already done it on that machine.

Athis

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Re: What UNI air filter to attach directly to carb?
« Reply #14 on: April 15, 2013, 05:10:52 PM »
Adding a second hose does not seem to contribute much if any more dirt while allowing the air flow of an open element.

Does that require re-jetting you think?