Author Topic: rad. cap question  (Read 1911 times)

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Offline maddoggy

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rad. cap question
« on: July 26, 2007, 05:09:11 AM »
monday and tuesday i rode my k5 in the dunes. by my own fault the gearing was wrong so i was forced to run a higher rpm than i was comfortable with which overheated the bike a little. i thought maybe the cap was bad so i bought a new (stock 1.1 Bar) cap. well the next day it still overheated. my "Q" is this, a 1.6 bar cap is an option for the k5. are any of you guys running this higher psi cap? 1.1bar = 15.954052 psi,  1.6bar = 23.205894 psi. correct gearing im sure will solve the heating issue by easing up on the engine rpms, but im still curious about that stouter cap. sure seams like alot of pressure to me. MADDOGGY

stewart

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Re: rad. cap question
« Reply #1 on: July 26, 2007, 05:15:29 AM »
i have had the stock caps not work the 1.1  ,,, you can get one for kike a 79 toyota pickup  at the parts store thatis an easy fix and i know people running 1.6 cap no problem

Offline hughes

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Re: rad. cap question
« Reply #2 on: July 26, 2007, 05:35:25 AM »
Could the bike be to lean for the dunes? Any time theres more load on the engine it would need to be richen up just alittle. The paddle tires and the sand load an engine real heavy. I figure you got your jetting correct for dunes if your riding in them all the time. my 2 cents spent. Have you changed the cooling fluid lately? If so did you bleed all the air out of the cooling system?
« Last Edit: July 26, 2007, 09:20:03 AM by hughes »
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Offline FuriouSly

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Re: rad. cap question
« Reply #3 on: July 26, 2007, 09:59:23 AM »
Overheating is always a factor when riding the dunes.  Running too lean or fat will cause excess heat along with high rpm's and slow speeds.

Riding with the wind and not allowing it to cool the rads will cause overheating, the most common reason for boil-overs at the dunes. Especially St. Anthony where the winds tend to run lengthwise with the dunes.

Rad caps rarely fail, but possible.  Higher psi cap?  Get the bike running right and pay attention to riding environment that causes boilovers is probably more important.  I personally like to see my overflow tube spitting some coolant. That way I know that I am down on power because of high temps.  Kind of a confirmation that everything is working right.

Got some pics of the trip??

Sly

Offline maddoggy

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Re: rad. cap question
« Reply #4 on: July 26, 2007, 10:55:41 AM »
sly, i do have pics of the trip. however, work piled up on me while i was playing in the dunes. i work nightshift tru the weekend so ill try to post some pics in a few days. the bike was running great and had lots of power but as i said earlier the gearing was obviously wrong. good thing i carried a bottle of h2o in my pack. by the way,i failed to mention that i weigh 210 lbs. thats alot o beef for a bike to haul around. oh well, wasnt to bad for her maiden dune voyage. many more in the future for my k5. MADDOGGY

Offline BDI

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Re: rad. cap question
« Reply #5 on: July 26, 2007, 06:02:19 PM »
Do not forget that you can have a blown head gasket between the cylinder and the water jacket you might not see anything leaking on the out side of the engine but the motor will pressurize the cooling system and cause water to shoot out the over flow. Are you running the fiber head gasket because they like to do that. Also If you over heat the bike and It shoots water out on the ground you should bleed the head or you could have a air bubble and the bike will over heat even easier than It did the first time. Just some more thing to consider
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Offline mg82

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Re: rad. cap question
« Reply #6 on: July 29, 2007, 04:17:21 AM »
i had a problem with the coolant boiling out the overflow. i bought a 16lb. cap from the auto parts store and works great. cost 6 bucks.

Offline BDI

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Re: rad. cap question
« Reply #7 on: July 29, 2007, 02:54:45 PM »
you know I have been pretty lucky I have never had my bike over heat at the dunes. I am using a cap from www.outlawracingproducts.com that Is a 1.6 but I only put that on as extra insurance.
Smoke every cigarette like It's your last and ride like you stole something!!!