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Discussion Starter #1
My 1999 Vulcan 1500 Nomad has a stock Keihn carb. This means it also has the coolant running through the carburetor via the small black "y" port at the bottom. I'm assuming this is to warm-up the carburetor faster. Well my "y port" is broken so it creates the following questions:

1. Does the coolant actually flow through the carb body through various or does it just go in and out of the black port?
2. I can bypass it for now (to get the bike running) until a replacement can arrive and be installed but will that cause an issue with the carb's performance?
3. Has anyone permanently by-passed this function and did it create other issues that had to be addressed?

Both myself and the Vulcan reside in the sunny West coast of Florida so I am not too concerned with carburetor "icing" issues.

Any guidance is greatly appreciated.

Cooper
 

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That modification was implemented because under "certain conditions", there can be a lean stumble.
You do not need freezing conditions for this to occur.
 

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the rad fluid does not pass thru the carb body, the fluid just touches the nipple Y joint which then transfers the heat of the rad fluid to the carb body, like metal to metal heat transfer, you can remove that nipple elbow altogether and just connect the rad tubes with a coupling and let the tubes just hang free, the removal of that rad fluid Y port from the carb will not alter any performance of your bike, just let the bike warm up a minute or 2 longer
 

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I would never recommend the defeat of a factory modification that was implemented for safety reasons, but that is up to you.
 

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I would never recommend the defeat of a factory modification that was implemented for safety reasons, but that is up to you.
Do you ever install a set of aftermarket exhaust, or a custom air filter ??? Same thing Modification of factory items.
 

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I did, and I ask you the same question. Mods are mods, safety or otherwise. After 60 years behind handlebars, I think all mods are OK.
 

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I think all mods are OK.
Well, I guess we will have to disagree. I would never, never, never, nor recommend, a change that might cost someone their life due to carb icing. It is a safety issue.

With 3 months behind the handlebars, I have found that blanket statements can be risky.
Ill conceived (look it up) modifications are out, in my book. Sorry.

But, like I said, it is up to the owner to do as he chooses...
 

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I disconnected and bipassed mine when I did my pipes and air, but Mr Fair is correct, I experience a low end stumble when its cold , even on cool summer mornings until it is warmed up. If it is in the 40s, it might take the better part of a morning before it stops coughing from a stop. But if you park it and go eat lunch, it starts allover again when I start out until it warms up.

I like to ride alone, anf I take trips that take me through the Rockies and places like Utah and Nevada, both of which have altitudes of 6-7000 feet plus. I encountered 27 degrees in yellowstone in June and 30 degrees and a frost covered bike in Nevada in early September at 6 AM. As soon as the snow is gone and I can ride again I'm hooking it back up. Having it hooked up doesntl hinder performance.
 

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Discussion Starter #11
Thank you all for your guidance. My takeaway is this:

1. The coolant doesn't actually flow through the carb body.
2. I can bypass it for now to get the bike running but I may encounter a "low end stumble" when the bike is cold.
3. While it can be "by-passed" the purpose is to eliminate a potential sluggish response so order the part and install it the way Kawasaki intended it to be.
4. There's a reason I live in Florida - good Lord 27 degrees in June. I start looking for salt for my driveway when the weather man says we may drop down to 40. :grin2:

Again - thank you all for the information.

Cooper
 

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That sounds more like you need to richen your carb, more than water heat it.
Once i thought so, and fiddled with it, but after a lot of trial and error, the carb is fine. When it's warm it runs like a champ, and with pipes, air and jets I am able to get close to 45 MPG. It didn't have that cold stumble before I disconnected the heat tube.

If you want to disconnect it, go for it. Makes no difference to me. I'm just sharing my experience with doing so. Your mileage may vary, and it might be fine.
 

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1. Experience is the best teacher.
2. Like I said before, temperatures do not have to be icy cold, only under certain conditions including humidity/temperature.
3. Carb mixture will have no effect on the above.
 
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