Raptor720,

<< I do enjoy not having that decompressor play hell with me on tight trails at low rpm's. >>

How does this effect tight trail riding? Does this make the machine stall more often?

 

I was wondering if it was causing the stalling or if it was a matter of too light of a flywheel or?? My thought was that the decompressor on some units may actually partially open at low rpm operation. On the machines that have had the decompressor removed, I have never heard of another carb blow off issue or that pesky stalling at low rpm usage.

 

wish i'd would have known that before i reassembled my engine, it would have been a lot easier getting the cam on without all that junk in the way
shollz that high comp piston is going to make that starter work a lot harder, so make sure all those cables can carry the current your starter draws, the stock ground wire actually connects to the case where there is a &quot;coating&quot; so you dont make as good a contact as it should, you can test it by running a jumper cable from the negative terminal to an uncoated part of the engine block and see if turns over that way

 

Guys, how is the decompressor disabled?

 

the decompressor is an assembly on the cam sprocket, to remove it (at tdc) you have to pull the rocker arm cover take out the timing chain tensioner, and i'm not certain if you can remove it without removing the cam or not, you will see it on the gear its a set of spring loaded parts on the gear held on by the 2 bolts that hold the sprocket on the cam and a spring connected to the gear, one word of caution if you remove the cam: keep the chain from falling into the case or you are in for a long day. 720raptor is more familiar than i am so maybe he can add more info, since i had no idea i could live without it

 

I am sure that there are a few ways to remove the decompressor. Here is how I do it.

First, you might simply want to have a weld shop add additional weight to the two throw weights. That would cause them to move out to faster and stay out at a lower rpm.

If you still want to remove the feature:
1. Remove the rocker cover.
2. Remove the two access covers on the generator cover. Using the center access hole, turn the crankshaft until the slot on the flywheel appears in the small access hole area. Note the position of the cam and marks on the cam sprocket.
3. Remove the two bolts holding the sprocket to the cam.
4. Remove the sprocket and cam. Don't worry about the timing chain falling. You can easily pull it back up with a coat hanger bent at the end or a long reach magnet.
5. Take a punch and knock out the two rivets (pins) that hold the two throw weights on the cam gear.
6. Observe the operation of the decompressor in the cam. If you turn the decompressor, it raises a pin in the cam lobe. That pin hits a rocker arm pad and causes one intake valve to remain partially open during compression.
7. Turn the actuator until the pin is down in the cam.
8. I then simply TIG tack weld the actuator in place.
9. Reassemble.
Note, if you remove the actuator, you could have a major oil leak in the top of the engine.

 

Thanks guys....never been inside the Raptor before. One tip that has been useful for me......the timing chain can be easily held outta the way with 2-3 long zip ties....zip tie too the bars, tab on frame, etc.

 

jon
thanks for the detailed post, I had wondered how that actually worked and that was a great explanation, not sure i'm willing to go that far on mine since I hope to not be in that deep for a while maybe when i do my post summer teardown

 

Just have a welder add some weight to the two weights.