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Exhaust cam - broken auto decompression

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I need guidance from the guru's. The auto decompression mechanism on my E model has broken. The small pin spins freely and slides back and forth and/but there is a very small broken piece of the casting that is located next to the cam lobe. The bike runs fine but there can be a ticking noise from the valve train that I think comes from the small slider pin on the mechanism. I did a compression check and I get 210lbs. (yes that’s right) so starting without the auto decompression can be an issue.

My questions;

Since the auto decompression is not serviceable, do I need a new exhaust cam?

OR

Can I remove the auto decompression and live without it? Will doing this hurt something else down the line?

Thanks for the help.

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Oh man my favorite subject. I had the same problem and now I remove the auto decompression on purpose. I will never run one again. The little pin that operates the one with the flat on it is gone and ground up in your motor. You might find a few traces of it in the oil pump.

Yes you can start the bike no problem without it. A good battery helps. Occasionally it will not crank thru, but you just hit the button again. I am still on the original battery (2000) and starting is beginning to be a little weak. Hot Cams replacement cams do not use the decompressor at all.

Remove the cam. Do not remove the sprocket from the cam. Grind 2 notches in the remainder of the auto decompressor and remove it with a chisel. Comes off easier than you think. You can leave or remove the retaining ring.

Now take a look at the bucket tappet. It has been smacked around by the decompressor pin. If it is damaged at all, replace it. The noise you hear may not go away until the tappet is replaced. Look for damage around the edge.

Report your findings. I replaced the cam and follower at the same time so I never knew which one cured the noise. Just removing the decompressor did not cure it. The noise you hear is probably from the tappet being spun by the cam not the decompressor pin hitting it.

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Thanks for the guidance boys. The pin with the flat in it is still attached/intact and there is no damage to the bucket, cam hold down, or bearing surface. I'll take the auto decomp today and report back how it went.

Thanks again gents.

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Yea, I know the pin with the flat is still there. The missing part is a cross pin that was in the side of the remaining pin and controlled the orientation of the flat spot. Take the tappet out when you have the cam out. (just lifts out) and feel for a burr around the outer edge. It looks perfect now but you will (may) find damage to it when you get it out.

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Noble,

You are spot on! The right side exhaust bucket had a little bit of roughness that I cleaned up with some 9 micron sandpaper. I cut out the 'C' shaped piece as well as the pin with a dremel tool. Total time, including clean-up, was about 20 minutes.

This site is an awsome place for information. Not all sites are this information packed and not all sites have members this helpfull. Everyone here should feel thankfull and proud to be a part of this brotherhood!

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The "C" piece is the movable weight, right? I would feel better if you took the collar off too. (the part the weight was attached to) There is a little alignment pin under the collar you must remove when you take the collar off. As I recall the collar captures the operating pin with the flat that contacts the lifter. I took the collar off to remove that pin. That pin with the flat has to go. As long as you are sure nothing else can come loose you are fine, but I removed everything I could.

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