Decompression system question

[eight0]

Hi all,

When i bought my bike there was no decompression cable fitted. I have ordered one and while i'm waiting for it to arrive i thought i'd pull the cover off the engine to see if it was all there.. it seems like when i pull the lever its not doing anything to the valve, theres just no more resistance when its off the bike then when its in. Does that make sense? Am i missing something integral to make it work?

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[kshansen]

Hi all,

When i bought my bike there was no decompression cable fitted. I have ordered one and while i'm waiting for it to arrive i thought i'd pull the cover off the engine to see if it was all there.. it seems like when i pull the lever its not doing anything to the valve, theres just no more resistance when its off the bike then when its in. Does that make sense? Am i missing something integral to make it work?

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Two things that come to mind, this might be off as I have not seen a decompression set up since I sold the one off my 1972 parts bike somethng like 15 years ago.

First question is does the engine have the right rocker arm for the compression release, I'm thinking there is a special arm used with that system.

Second, note that if the engine is stopped with the exhaust valve for the left cylinder at or near the top of the cam lobe the valve is already open so the compression release has nothing to do! Tun engine over a bit to make sure the valve is closed and try again.

I know I said two but a third one came to mind! Are the valves adjusted to the correct clearance? If too loos the compression relief may not function. I know it is a major problem on some overhead cam Briggs engines!

 

[eight0]

Thanks khsansen, I'm being stupid, you were right with point 2.. of course it has nothing to do with the left valve open!