Drive sprocket nut won't stay tight

[Grundy]

Hi all,
I seem to be having a problem with my front drive sprocket. I on my latest ride it came loose, meaning that the bike would keep rolling forward without turning over the engine when the clutch was released. I thought it would be a simple fix, but it has turned in to quite a headache. No matter how hard I tighten down the nut that keeps the sprocket on, it comes loose again every time I release the clutch when the bike is moving forward. No amount of lock tight or muscle will get that nut to stay, each time it comes loose as soon as I release the clutch. Am I missing something here? Is there a part that fell off or is there a special way of tightening it? Thank you for any suggestions!

 

[Rob H]

Sounds like a spacer or something might be missing I would take a real close look and see if the chain is striking something

 

[crassius]

I think you're missing the woodruff key that locks it to the shaft.

 

[45u]

Make sure you have the woodruff key in and use a drop or two of blue loctite. All so if you take the clutch cover off you can use something between the gears to lock it up so you are able to get it good and tight. I take my clutch apart and use the nut holding the clutch to the shaft and hold it there with a wrench while I tighten the front sprocket nut and ALWAYS use a drop or two of blue loctite.