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Thermostat

J

JimBridger

Well-known member
Mar 11, 2013
206
145
43
SE Idaho
Yup. Put it in a pot of water and boil it. See if it opens just before it boils.

It opened just fine. I installed it the same way as I have seen others install it w/out a bypass Have you guys been reading temps in the head or at the hose/Thermostat?
 
B

Bigred1

New member
Oct 26, 2013
43
4
8
57
Anybody put a stat in an original (not Aluminum frame) KX500. The outlet from the head to the radiator is only about 1/2 inch apart. was thinking of eliminating the left radiator (would it over heat) or putting in-between the left and right radiator but I don't think it would work there.
 
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ravenous

Well-known member
Lifetime Membership
Oct 21, 2013
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Im riding a 94 kx 500 too. I removed the left rad. Then from the fitting on the head comes a temp sensor then a 180 deg.thermo bob then on up to the right rad.The bypass hose goes from the t-stat to the pump.The way that original left rad fits in there makes adding this stuff impossible.Yesterday was my first ride on this setup.I saw temps from 160 to 230 deg.Hopefully we can get by without that rad especially with warmer spring temps.
One other mod Im super happy with is a decompressor on the head.Larry Wiechmann did the head mod for me.Its a work of art and now its REALLY easy to kick.
 

summitboy

Well-known member
Premium Member
Nov 26, 2007
2,146
851
113
Thise are pretty high temps for a 2 stroke imo. You need the new bob lol
 

ravenous

Well-known member
Lifetime Membership
Oct 21, 2013
170
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43
Ya, it is a little hot for sure. But even with the new bob the max temp wont decrease.Its overheating cuz I only have one rad.At least it isnt boiling over.
This temperature thing might be challenging.
 

ravenous

Well-known member
Lifetime Membership
Oct 21, 2013
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With the left rad in there is no room for a t-stat or a temp sensor.
With both rads in and no t-stat it runs ice cold.
 
D
Aug 29, 2010
244
41
28
Vancouver, BC
i tried one rad on my cr500, couldnt keep it cool on setup up snow and warmer temps. i just put the other one back on and put valves on each side, one side has extra long hose that runs around the carb for heat. test it out this weekend and hopefully i have enough control over the temps
 
D
Aug 29, 2010
244
41
28
Vancouver, BC
It opened just fine. I installed it the same way as I have seen others install it w/out a bypass Have you guys been reading temps in the head or at the hose/Thermostat?

does it have a small hole so that there is some flow? without some the temps are head will be very hot and at the thermostat not warm enough to make it open
 
J

JimBridger

Well-known member
Mar 11, 2013
206
145
43
SE Idaho
does it have a small hole so that there is some flow? without some the temps are head will be very hot and at the thermostat not warm enough to make it open

Yes, it has two, but they are very small.... like 1/16th inch. I may enlarge them.
 

summitboy

Well-known member
Premium Member
Nov 26, 2007
2,146
851
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With those holes in the stat you get plenty of flow to open the stats. You may just be overheating if it keeps climbing to 200F.
 

summitboy

Well-known member
Premium Member
Nov 26, 2007
2,146
851
113
If he is measuring temp out of the head and before the stat and he sees the 195F then that stat is open. He already tested it and said it opened fine. He is just getting too much temp. Is this a FI bike ? Carb ? Jetted or fueled right ? Gearing ?What kinda snow condition. If your just running a hard pack trail then the bike can overheat.
 
J

JimBridger

Well-known member
Mar 11, 2013
206
145
43
SE Idaho
I just threw it back on the bike, and now it's working like it is supposed to. When I took it out of the housing and was inspecting it, I compressed the spring a few times and threw it into the hot pan to test it. I wonder if it was sticking. Anyway, it works fine now. I also enlarged one of the openings, so that could def be it too. Thanks everyone for the help! It's nice to be able to get some decent opinions and how to on here!!
 
B

Bigred1

New member
Oct 26, 2013
43
4
8
57
Im riding a 94 kx 500 too. I removed the left rad. Then from the fitting on the head comes a temp sensor then a 180 deg.thermo bob then on up to the right rad.The bypass hose goes from the t-stat to the pump.The way that original left rad fits in there makes adding this stuff impossible.Yesterday was my first ride on this setup.I saw temps from 160 to 230 deg.Hopefully we can get by without that rad especially with warmer spring temps.
One other mod Im super happy with is a decompressor on the head.Larry Wiechmann did the head mod for me.Its a work of art and now its REALLY easy to kick.

I'm thinking of reversing the flow through the radiators or relocating the bottom inlet to give more room for the stat. does anyone make a compact smaller thermostat?
 
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