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exhaust cam pin

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It shouldn't move that much, the pics aren't clear enough but you must be missing a smaller pin (about 1/16" dia) that locks the larger one in place and makes it turn.

If that small pin is in place there must be something wrong, if it's missing you shoud look for it before it does any damage to your engine.

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Is the pin next to the black mark still intact....The point of failure is that small pin will break off or fall out. Then the cross pin just free wheels and contacts the valve lifter randomly.....

auto_decomp3.jpg

The small pin on the right of the black mark can become dislodged .. it controls the movement of the pin on the above left of the black mark..

The 2 pins are connected ......as shown below..ignore the red arrows

tappet_pin-1.jpg

I suggest removal of the whole decompressor unit...

Edited by CraigoDRZ400sm

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The pictures in post 2 clarify how it should look. Yes, there is quite a bit of lateral slop in the pin. If your auto decomprssion mechanism is all there and functional, you are good to go. However, some people (self included) choose to remove it to avoid possible failure.

If you choose to remove, cut and break off. Don't remove the sprocket.

Oh, now I see your arrows. Looks bad to me. I bet the little cross pin is gone and that pin free spins.

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thanks for the replys,,,,,yeah the pin is missing i have looked on the suzuki parts diagram and it only shows the cam complete..where could i get this pin from?

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thanks for the replys,,,,,yeah the pin is missing i have looked on the suzuki parts diagram and it only shows the cam complete..where could i get this pin from?

Your original pin should be floating inside of your engine and you need to retrieve it before it damages gears and then bearings.

If you do a search, failure of this pin is somewhat common, the suggested preventative action is removing the complete mechanism before the pin falls off. I was reluctant to remove the decomp mechanism but I'll do it tomorrow while the cams are off before this happens to mine.

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You can't (or at least should not) replace the broken pin. Just remove the rest of the mechanism. If the broken part has been gone very long, the motor has eaten it and it is in the oil filter. But you should at least look for it. If you can't find it intact, inspect the teeth and valleys of the oil pump for debris (that is where I found mine) and replace the plastic oil pump drive gear.

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If your lucky it may one day appear on your sump plug magnet....or even more lucky would be for it to have come out when emptying oil during an oil change, perhaps unnoticed...

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Oh, now I see your arrows. Looks bad to me. I bet the little cross pin is gone and that pin free spins.

DSC01058.jpg

Concur, if that picture is showing what it looks like, that pin all the way out of the bore, till it hits the cam lobe.. The retaining pin is broken or just gone...Time to break out the cut off tool and chop that thing off.. Oh, and find the missing hardened pin.. it will do a number on the transmission and various bearings.

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i have had the bike for 3 months and i have done 2 oil changes si it might of gone un noticed..it might of been like this foe a while because where the pin has been moving over it has marked the edge of the tappet or bucket..

i will still have a look for it

what do you mean removing the complete mechanism dont you need it ?

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Mine was tapping quite loudly i found that it was worn to the point of being off centre. Removed the whole lot and quite as a lamb , well as quite as a open Yosi will alow !!!

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The compression release does what its name implies. It bumps 1 of the EX valves momentarily at cranking speed to reduce the compression pressure to make the motor easer for the starter motor to turn over. With a good battery to power the starter motor, the auto compression release is not needed.

My lawn mower had the same devise. It also failed.

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one last question do i just cut the pin off or the arm with the spring on or the whole thing

thanks for the replys

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The whole stinking thing, I used a dremel with a small cutoff wheel and cut at the thin spots where the 90 degree bends in the ring are and then twisted it apart with a channel lock.

The part that bugs me now is that I don't remember if mine had the small retaining pin still intact or not!! Damn it!! I seem to vaguely remember that my pin would come all the way across to the lobe also. I guess this really moves the big bore kit up a little bit.

Where the hell do you look for the pin at? Is there a most likely place it will end up that is easy to get to? Pull the side cases? I just did the TT oil change kit like 300 miles ago too, and pulled the screen, nothing found!

Oh yeah, if your starter is weak, as in worn brushes, this decompressor removal will point that out rather quickly.

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You will like the way it starts once it is removed....it fires on the first power stroke instead of like 3 turns later.

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