Auto decomp question

I didn't know where it was on my engine until I read a thread yesterday with a pic. So I was looking at mine for s & giggles and see that the center "knob/shaft" is loose. It was out about a 1/4" and I pushed it in. I'm wondering how long it's been loose and if it can fall out. Why would it be loose anyway?

What do you guru's recommend? I plan to ride tomorrow.

Thank you!

I say take the cam out and use a dremel and cut it about half way to the cam 180 degrees apart. Then take a chisel and lightly tap it the cuts and it will break right off. clean the cam reinstall and ride enjoy sound of the engine with out the annoying tick tick tick tick tick. Im glad I did this.

Does the S not have the auto decomp like the E model does? My E engine looks different than the S engine's I've seen

All oem cams has the decomp unit (and hotcams stg 1)

All oem cams has the decomp unit (and hotcams stg 1)

IIRC the kicker model does not have the auto decomp.

Are you asking about the auto decomp that's mounted on the cam and is inside the engine, or the manual decomp that should be connected by a cable to a lever on the handle bars?

S model only has the auto decomp.

S model only has the auto decomp.

The E model also has the auto decomp.

I meant that the S model has the auto decomp and not the manual decomp (has auto decomp only) not that it's the only model with an auto decomp. Sorry for the poor wording.

He's riding an e, so when he says he pushed in the knob/shaft it makes me think it's the manual decomp that he's talking about, and maybe he's missing the cable and assorted hardware.

I took a pic of the part that is loose. :ride:


I took a pic of the part that is loose. :ride:


That's the manaual decomp(or could have been..)

If you have the manual decomp , the bolt is replaced with the decomp bolt .

is the bolt that retains the shaft from the front of the head there?

I'm not sure what you mean Eddie. Is this bolt on the outside of the engine? Where do I look? Thanks!!


in this pic I pushed the shaft in

there is a bolt on the front of the cylinder head that engages the groove in the shaft.the only way its possible for the saft to come out is for the bolt to be missing or the bolts is wrong bolt with out the "nipple" on the tip of the bolt.

look around the corner on the front f the cylinder head where you are taking the pic.

there is a bolt that holds the shaft that you pushed back in , you will see a hole where the bolt should be .

look at the top of the head just behind the philips screw holding the bracket on in the top pic . the bolt fits perpendicular to the bracket to hold the shaft in .

You can see the bolt in this picture. You can see where the decomp shaft is, and to the left (the part of the head that faces the radiators) you can see a bolt in line with the shaft. If it is loose, or the wrong one, that shaft can fall out.


Thank you guys!

Went out and looked and a bolt is there and hasn't moved. So I'm guessing either the shaft broke, allowing it to come out or the previous owner didn't put in the proper bolt and it's been like this forever.

So where do I get the correct bolt to hopefully fix it?

And does my bike not have the auto decompression then?

Is it a manual decompression with no way to decompress it? lol

Thanks again!

(what would happen if I would try to pull it all the way out?)

nothing to do with the auto decompressor.

the shaft is simply a dummy shaft plugging the hole for manual decomp that comes with the kickstart kit.

Hmm, so I still have the auto?

Do you happen to have the right bolt to hold the shaft in Eddie? OR could I just remove the bolt from the front and buy a longer one and dremel down the tip so it's somewhat pointy? Will oil come out if I remove the bolt?


you still have the auto decomp , as eddie just said .. its for the manual decomp .

get the right bolt from the dealer , my parts list does not show the bolt or give a part #

oil will not come out if the motor is NOT running

I can't find the bolt on online parts lookup...


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