Coolant is passed through the carburetors on this bike. This is done not to cool the carburetors but to heat them. The idea is to prevent the formation of ice in the carburetor throats as fuel is evaporated. Fuel evaporation can cause extreme temperature decreases in the throat of the carburetor. During particularly humid and cool weather conditions such as riding in clouds or fog, ice could form in the carburetors and prevent the engine from running.
That is the theory. In practice this rarely happens. There is also a downside to this carb heating. At upper elevations and at high temperatures, the heating of the carbs can be excessive and actually cause the fuel to boil preventing the engine from running. There have been many reports of this condition arising while I have heard no instances of carb icing on this motorcycle.
It is a very simple job to bypass or remove the coolant lines running to the carburetors. I chose to remove them entirely. Another benefit to this mod is the cleaner engine area resulting from fewer hoses and clips.
Removing the hoses leaves some spigots exposed and in need of capping. I had the three carburetor synchronization spigot caps available after replacing them with the Carburetor Equalization Manifold plus the unused cap from Ivan's Air Induction System Removal Kit.
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Do not attempt this while the engine or the coolant is hot. Allow it to cool first.
Start with the coolant hose running from the left side of the carb bank all the way to the radiator on the right side.
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Disconnect the hose from the right side of the radiator first using pliers to open the hose clamp and place a rubber cap over the spigot. Do this quickly because coolant will begin to come out of the radiator. Some coolant will also drip from the hose so have a rag handy to catch it and to clean up the spillage.
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Now you can pull the hose through from the left side after unhooking it from the guide clip on the left side. Point the end of the hose into a jar to catch more coolant spilling out from the hose. Then detach the hose from the left side of the carburetor bank. Do not place a rubber cap on that spigot yet.
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The hose guide clip attached to the larger radiator hose can be removed entirely.
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Move to the right side of the bike and note the coolant hose running from the right side of the carb bank through a one-way check valve up to the thermostat housing.
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Disconnect the hose from the thermostat housing and plug the spigot with a rubber cap.
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Disconnect the hose from the right side of the carb bank and pull the hose down through removing it and the one-way check valve completely. Do not put a rubber cap over that spigot yet.
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Select one side of the carb bank (I chose the left) and use a suction device like the MityVactm to draw out the coolant left in the carb bank.
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Now place rubber caps over the spigots on the left and right sides of the carb bank. These are not critical and the rubber caps just serve to keep dirt from entering the carb coolant channel.
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These are the hoses and clips that were removed. The engine area is now even cleaner and more accessible than before.
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Check for leaks at the radiator and thermostat housing during your first ride afterwards.
Addendum:
There have been reports of rubber caps leaking after a time particularly those of cheaper quality rubber. Mine seem to have held up but
they can eventually dry and rot then coolant can start to seep out, or worse yet, blow completely and spill a lot coolant. One solution is
to use a length of proper coolant hose to bridge the two radiator spigots. Be sure to use a good hose clamp on the ends to ensure
a tight fit. I will likely do this soon as preventative maintenance. Here are the two ends to connect with the hose.
From Tom G. aka 'ABH' of the Owners Association comes this photo showing how the stock hose is used to connect
the two ends.
Last Updated: 07-30-2005
Copyright © 2001-05, Patrick Glenn, All Rights Reserved.
The information presented here reflects solely my personal experience with my motorcycle and is presented
for entertainment purposes only. No information presented here is to be relied upon for issues of rider safety
nor to replace the services of a qualified service technician.
Any attempts to follow or duplicate any of these procedures are done so completely at your own risk.
By reading the information on this site, you agree to assume complete responsibility for any and all actual
or consequential damages that may arise from any information presented herein.
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