Author Topic: stock carb mods Q?  (Read 767 times)

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Online Don R

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stock carb mods Q?
« on: September 23, 2023, 12:02:20 PM »
 I've found one or two Keihen carb racks with the slides notched a little more on the air filter side, I'm assuming this was a performance mod but was wondering, what's the advantage?  Does it help off idle air flow?  Neither set appears to be bored or have other modifications. 
« Last Edit: September 23, 2023, 12:59:54 PM by Don R »
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Online Don R

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Re: stock carb mods Q?
« Reply #1 on: September 23, 2023, 04:01:11 PM »
 Like this, the set on the left are complete and were working on my 836 Hot Rod before I got the adapters for 29 smoothbores. I may try them on my 836 diecast bike.
No matter how many times you paint over a shadow, it's still there.
 CEO at the no kill motorcycle shop.
 You don't need a weatherman to know which way the wind blows.

Offline Tracksnblades1

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Re: stock carb mods Q?
« Reply #2 on: September 23, 2023, 04:26:28 PM »
Higher the cutaway the leaner the slide.
Shops used to cut the cutaway as part of the carb tuning for engine mods.

Kiehin offer slides from .5 to 9.5 for some of their popular offerings. It’s still cheaper to cut them yourself if you’re set up to.. $69 for a new slide vs $10 to have them machined.

It can be confusing if theyve been modified and not marked..
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Offline seanbarney41

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Re: stock carb mods Q?
« Reply #3 on: September 23, 2023, 07:30:08 PM »
I remember CycleX used to offer this slide modification...I think they claimed that it helped with those tricky off idle to low lift throttle position type tuneing problems.  I do not think it is on their website anymore.
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Offline seanbarney41

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Re: stock carb mods Q?
« Reply #4 on: September 23, 2023, 07:34:39 PM »
I have a bike that has always had a problem in this range and nothing I have ever tried made a difference.  The engine is a stock displacement K5 with a home ported head and F2 camshaft.  Lately, I realized I have a #$%* ton of extra carbs and maybe I should try this.
If it works good, it looks good...