KX500 GOVERNOR REBUILD, WHY BOTHER?

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It is one of those often overlooked items on your rebuild.
After all you have a cool crank rebuild, a awesome top end rebuild.
You put all new bearings, seals, gaskets, clutch plates, yada, yada, why bother with the governor???
Simple... If you blow a bearing in it and they go through the engine you just rebuilt, what do you think it will cost to start completely over?

So, let's take a look...
Here is your KX500 Governor.
What a beauty

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Let's take it apart and see what it looks like inside..
First, depress the plastic gear until you fully expose the small steel pin, then pull the pin out..

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Lay the parts out on your work bench in the order they come off the shaft.

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Next I will show area's that I look at and some polishing that I do... Not that it is completely necessary but hey, I like they way things looked polished

Take a look at this pic.
You can see that the ball bearings roll right down the center...
That is a area I like to polish.
You don't need to polish the entire channel but the area in the middle of each channel can be cleaned up.

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Here is a list of parts that I automatically replace.
The prices are full retail as of 9-6-19.
Most parts houses will sell them for less.

1) SPRING,GOVERNOR 92081-1934 5.58
4) SPACER,15X28X1 92026-1238 6.54 each - total 26.16
2) BEARING-NEEDLE 92046-1252 11.48 each - total 22.96
1) GEAR-SPUR,GOVERNOR 59051-1213 - 12.04
1) RING-O,5.5X1.5 92055-1343 - .45
Grand Total: 67.19

Of course, depending on wear, you may need to replace additional parts as well...

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Before re-assembly, I clean up the insides of the governor housing.
I start with a 80 grit flapper wheel then I go to a 180 Grit flapper wheel.
You can continue to polish beyond that but there isn't really any good reason to do so unless it makes you happy

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With all new bearings, bushings, shaft, and gear installation is fast an easy..

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One other note...
I have 4 different governors to test.
The first is stock.
I have already Dyno'd it and know how it comes on and operated.
The second is a heavier spring than stock.
That will make the valve open slower and should provide a easier bottom end but it should hit harder on top.
The third uses two Tungsten Carbide bearings and two stock bearings.
They are installed across from one another to maintain a good balance.
Opening quicker than stock should make the bottom end hit harder.
Last I installed all Tungsten Carbide bearings which should make it open extremely fast.
Likely this will only be good for dunes, drag, or desert as the bottom end should be brutal.
Of course, we could lock the valves funny open
Once I have all the info I will post what I find..

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Here is two completely ready to go..

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