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Discussion Starter · #1 ·
Whats the easiest way to get to it? Would like to do it myself becasue the local shop wants $55 hr labor...Keep in mind i've never really worked much on four wheelers but would like to learn.....
 

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carbon build up is unlikely, the decompression is just weights on the cam sprocket and a shaft that goes into the cam with a pin that bumps one of the rocker arms and holds a valve open. when the motor fires the weight move outward and allow the valve to close normally.
 

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It's more likely the springs/kickouts that aren't functioning properly, doubt there's any carbon buildup on the camshaft.

But to get to all of this stuff you need to pull the valve cover. Step by step instructions can be found at raptortranny.com, just follow the part of the "01 trans update guide" that deals with the head cover, I think it's page 3 or 4.
 

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Discussion Starter · #6 ·
well something with the compression release not opening up....replaced starter motor....selonoid...one way is good...all gears check ok...so yea im here now.
 

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Have you done a compression test?

There are still a handfull of things that could keep it from starting too. The other question is will it run if you pull/push start it?
 

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Discussion Starter · #8 ·
no...burnt upp the selenoid and pretty much cooked the starter from where the starter motor will not turn over the engine....yes if i roll it off it will fire everytime.
 

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Assuming for a moment that you had no working compression release whatsoever, the bike still wouldn't do that to the starter or solenoid.

I'm going to assume at this point that you've gone through all your essential electrical connections to check for both connectivity and proper voltage. And if you're ready to tear into the engine then you should already popped open the stator side case (clutch side) and made sure the gears and one-way were intact, unbound, and functioning properly.
 

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Discussion Starter · #12 ·
popped it off...noticed that the pin is rough at the end...my ? is how do i get the pin out??? Do i have to take the cam out??? Any help appreciated!!
 

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http://www.yamaha-motor.com/sport/parts/home.aspx
Step 1, atv parts
Step 2, year
Step 3, model
Left side of screen, camshaft chain.
This will show you an exploded view of the assembly.

In item 5 notice the flat, this allows the pin to retract when the weights move out to the running position and the valve will poperate normally.

The 2 bolts in the end of the cam hold the weights in place, they inturn, rotate the shaft inside the cam which raises the pin that lifts the valve to decompress the motor for starting.

The bolts are removed and the weights will then come off, this will let you turn the shaft and watch if the decompression pin pokes out of the cam. With the shaft turned and the pin sticking out of the cam the shaft can be pulled out of the cam. There will be a spring and the pin inside the cam, they will slide out the back of the cam.
 

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another problem that may have been overlooked is that something may be binding up the starter-to-one way gear. It will let your bike be push/pull started but not conventionally started. check the #13, #17 gears if you haven't already.
 

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I'd be happy to help you trouble-shoot it if you call me at 757-397-1462, I expect you have more than one problem because that pin doesn't wear much and if it does wear any its smooth not jagged as you describe. If its jagged, it means it has broken off, you'll need to find the broken piece in the motor BEFORE you start it, I'd also recommend you pull the clutch side cover and inspect the plastic oil pump gear for stripped teeth.
 
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