Author Topic: Choke Cable Mod  (Read 2819 times)

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Offline SndyRds

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Choke Cable Mod
« on: December 23, 2009, 04:11:22 AM »
One of my Best friends (who has since passed on) had a MOD to add a lever style flip up choke cable  (off of a Yamaha PW50) mounted, on the bars, or radiator scoops.  He used it for high speed riding in high heat conditions (Racing) to use the enrichment circuit to add a small amount of fuel cooling.

Has any one done this? Or know of anyone who has. I believe I need to know how to interface the cable to the KX 500 Choke plunger.

This was back in the 80's...  I hope the knowledge is not lost.

Thanks for any help.

Sandman


Offline ID KX500

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Re: Choke Cable Mod
« Reply #1 on: December 23, 2009, 04:54:11 AM »
I think the cables are common on carberated snowmobiles also.
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Offline ShadeTreeFab

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Re: Choke Cable Mod
« Reply #2 on: December 23, 2009, 05:07:39 AM »
i kind of like this idea, the plunger isn't that different then some of the hot start plungers I've messed with.

Offline jfabmotorsports.com

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Re: Choke Cable Mod
« Reply #3 on: December 23, 2009, 05:09:42 AM »
Does the PWK even flow fuel though that circuit above an idle?
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Offline don46

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Re: Choke Cable Mod
« Reply #4 on: December 23, 2009, 05:44:36 AM »
Does the PWK even flow fuel though that circuit above an idle?

The idea is that when you've ran for extended wide open throttle runs, you can flip the choke and when you chop the throttle it will richen the circuit, theoretically preventing seizure. They used this approach on the Baja and some high speed deseret races
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Offline Friar-Tuck

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Re: Choke Cable Mod
« Reply #5 on: December 23, 2009, 07:26:24 AM »
  JFab,
 Yup, the choke will allow fuel to enter the carb at any time if it's pulled.

That's one of the ways to check your jetting.
   If the bike runs better with the choke after it has been warmed up your probably lean.

  The hard part is to do this while running.
 The choke cable is a good Idea in my opinion.
So simple yet it never crossed my mind.
    I have heard of open desert guys hitting the kill switch to allow some extra oil/fuel run through the motor on extended WFO , which would accomplish pretty much the same thing as the choke cable. 
  Tuck\o/
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Offline Dutch-K5 Fan

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Re: Choke Cable Mod
« Reply #6 on: December 23, 2009, 08:09:09 AM »
Our Dutch pride Kees van der Ven, former KTM 500 2T Factory rider from the 80's used a
cable operated choke with beache racing to richen the air fuell mixture as the Baja guys.
It's on my VERY long list of K5 goodies :-D :-D


Dutchie
Proud owner of a KX500AF

Offline don46

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Re: Choke Cable Mod
« Reply #7 on: December 23, 2009, 08:14:06 AM »
Does the PWK even flow fuel though that circuit above an idle?

your right when the throttle is wide open there isn't enough vacuum on the circuit to draw fuel, but as soon as you chop the throttle then the velocity through the choke circuit will pull fuel. evidently there was concern of a lean spot on deceleration, the choke would richen it up to prevent burn down.

When running down groomed trails for miles at wide open, I'd pull the choke on my snowmobile prior to chopping the throttle, did I need too. probably not but it must make me feel better.
« Last Edit: December 23, 2009, 08:18:05 AM by don46 »
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