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YZ450fx Thermbob install

4
Dec 17, 2016
9
0
1
My Thermbob should arrive in the mail today and Im going to install ASAP. Anybody have any experience and or advice you can give me for this install? Thanks!
 

peakperf

Member
Lifetime Membership
Nov 28, 2007
11
7
3
Cranbrook, BC
The main thermostat housing is easy, the lower T-block to tie in the return line is extremely tight into the stock hose. Easiest is to remove the hose from the bottom of the left rad and the "y" into the block and install the aluminum T on the bench. Lube with coolant so you can rotate the T after you put the hose back on the bike to get clearance from the exhaust.
 

dooman92

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Mar 1, 2010
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Good advice on the bypass t above. If you are not going to add the fan then mounting the main housing is pretty easy. It goes in the largest hose. That hose comes off the cylinder block and goes to the top of the right rad. Mine is mounted at the top of that line almost touching the rad tube. You can use 3/4" auto hose or cut the stock hose.

If you plan to add the fan kit you will need to use the stock hose in order to get the clearance needed to accommodate the fan. I cut about two inches off the top end of the hose and used that between the rad and the top of thermobob. In order to fit the remaining piece, I mounted the thermo and visually fit the remaining hose from the bottom of thermo back to the cylinder. I ended up cutting the flared end off the stock hose in order to get the right angles to keep the hose and thermo from binding hard on the fan.

If you cut that flared end off the hose, it will go over the cylinder fitting but needs a little rubber friendly lube to slide over. Good luck.
 

Snow Fever

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Dec 14, 2007
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BC
If you go on Bobs web site he has very clear instructions with very good pics showing exactly where you cut and install. Just did one on my yz450FX and it was easy. My bike ran very good today and it was minus 13C. My motor was nice and warm and the rads were luke warm
 

jrusher

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Dec 1, 2007
498
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Edmonton
Put a temp gauge on that thing to there is a port for one on the thermostat and run and engine shroud as well. Soon as you drop into some deep powder your engine temps drop off huge the shroud helps keep those temps up.. The warmer your oil is the happier your engine will be
 
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