Hi everyone, i'm not new to the forum, i just never posted before. well i went riding the other day and got on a nice stretch of trial when it happened. Now my choice of words may not be correct but i'll do my best. As i was going on my merry little way with my 2000 650ds, it decided to throw the "front sprocket nut" off into the woods and so the sprocket/chain came off and i'm lucky to still have foot. Anywho, i need to find a replacement "front sprocket nut" but i have no idea what kind it is or what it looks like or size or any of that stuff. I dont know if its even called a front sprocket nut. Anyone have any idea as to where i can get one, or the size/dimensions of this mystery nut? any help would rock

 

You will probably have to go to a shop or dealer and order a new nut they will know what you are talking about. Also you will need to order the nut locking washer that is located between the sprocket and the nut so you can bend the nut locking tab so this will never happen again.

 

I think your looking for these:

M20 hex nut Part#: 420242651 Probably about $10

Tab washer (lock washer) Part#: 420245391 About $10 also.

And yes, you will probably need to get them from your bomb dealer, or possibly a bmw dealer, but the part#'s will be different from them.

Hope this helps

 

In a pinch. . .

There are two of these nuts on your swing-arm pivot bolt I think it is. . . you can take one off and use it. That lock-tab-washer is key. Make sure you bend the tabs down over the nut after she's on there good n tight. That will keep it from backing off and frisbee-ing into the woods.

Don't go cheap on this. . . get the right nut and tab washer from the dealer. Actually, get two of the nuts and 3 of the washers. . . if you ever have to change the sprocket, you'll want a new tab washer if the old one is in bad shape.

 

I keep a few but have never lost one using the wash. A little loc-tite is not a bad idea either

 

yea there is a nut and a washer behind it and check to make sure that your case saver which is behind your chain cover isn't all bent or else I would get another one if it is.