29mm Smoothbores

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steve murdoch icoa #5322
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29mm Smoothbores

Post by steve murdoch icoa #5322 »

Just something different to look at.
I just finished a full refurb of my Mikunis. Ulta-sonic, carb dip, guitar strings...the works.
Gaskets, o-rings, and info from Z1 Enterprises.
Hopefully be going on the '79.

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Jeff Bennetts
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Re: 29mm Smoothbores

Post by Jeff Bennetts »

JP has been running them for years and swears by them, maybe he'll chime in.

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Re: 29mm Smoothbores

Post by kbart1 »

those look awesome Steve! i can only wish! great job!

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NobleHops
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Re: 29mm Smoothbores

Post by NobleHops »

steve murdoch icoa #5322 wrote:Just something different to look at.
I just finished a full refurb of my Mikunis. Ulta-sonic, carb dip, guitar strings...the works.
Gaskets, o-rings, and info from Z1 Enterprises.
Hopefully be going on the '79.
Very cool Steve!

But I'm puzzled by the straightness of the bank of carbs. Wouldn't that vary the length of the intake tract in a bad way?

N.
Nils Menten
Tucson, Arizona, USA
'82 CBX, among others.

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Jeff Bennetts
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Re: 29mm Smoothbores

Post by Jeff Bennetts »

NobleHops wrote:
steve murdoch icoa #5322 wrote:Just something different to look at.
I just finished a full refurb of my Mikunis. Ulta-sonic, carb dip, guitar strings...the works.
Gaskets, o-rings, and info from Z1 Enterprises.
Hopefully be going on the '79.
Very cool Steve!

But I'm puzzled by the straightness of the bank of carbs. Wouldn't that vary the length of the intake tract in a bad way?

N.
You compensate with different length carb boots, similar to the intake on the CBX, it's not perfect but the tracts of the CBX head are so unequal I don't think it matters much.

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Re: 29mm Smoothbores

Post by EMS »

Jeff Bennetts wrote:[ the tracts of the CBX head are so unequal .

That's why the Honda engineers gave the CBX an airbox and designed it the way it was. One of the reasons pods don't work that well on a CBX.

I think Larry Benjamin had a set of smoothbores ( I maybe wrong) on his CBX and he loved them too. Rick's Tricks had a set of special carb boots available when he sold his Flatslides for CBXes

steve murdoch icoa #5322
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Re: 29mm Smoothbores

Post by steve murdoch icoa #5322 »

I do have the Ricks Tricks manifolds that are in surprisingly good shape.
A couple searches has provided info from Larry Benjamin, J.P. and John D. from Kansas.
Larry even used different jetting on carbs 1 and 6. PipeMasters and K&N pods will be going on mine.

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Jeff Bennetts
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Re: 29mm Smoothbores

Post by Jeff Bennetts »

The big reason pods don't work well on stock CBX carbs is they need vacuum to move the heavy slides they use, that's one reason why they are called constant velocity CV carbs and the fact that they automatically adjust to different altitudes, the lack of vacuum affects the throttle response because the slides have to catch up the the fuel flow. The 29 smooth bores aren't CV and don't suffer this problem when using pods, the Siamese pods now sold for stock CV carbs are better than the single pods though.

Rick is still around and I do have his contact info if anyone needs it.
Last edited by Jeff Bennetts on Wed Mar 14, 2012 9:28 am, edited 3 times in total.

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Re: 29mm Smoothbores

Post by Jeff Bennetts »

EMS wrote:
Jeff Bennetts wrote:[ the tracts of the CBX head are so unequal .

That's why the Honda engineers gave the CBX an airbox and designed it the way it was. One of the reasons pods don't work that well on a CBX.

I think Larry Benjamin had a set of smoothbores ( I maybe wrong) on his CBX and he loved them too. Rick's Tricks had a set of special carb boots available when he sold his Flatslides for CBXes
Exactly, I bet 90 percent of CBX owners have never opened up the intake portion of the CBX's airbox to see the different lengths of the intake runners inside.

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