Opinions on this sprocket please

[EricV]

Hi gang. My 630 has about 7K on it. I've gotta admit for the first several thousand miles I wasn't as good about chain maintenance as I should have been, so the chain is toast (some stiff links I can't work loose.) A while back I bought a chain, but have not put it on yet. Now I know it's smartest to replace the sprockets at the same time, but still can't help but wonder if this stock rear still looks good. The teeth look to be the right pitch, but the "valleys" are looking a little wide...but maybe I'm reading into it. Please let me know if you'd run it a few more miles. My CS sprocket, by the way, is only about 1500 miles old. Oh, and another BTW, those aren't ridges along the edge of the sprocket, it's the pushed down build up of various lubes. Thanks!

 

[Xcuvator]

I would definitely replace it. The drive side of the teeth is way laid back.

 

[Borgschulze]

The teeth shouldn't be pointy.

 

[EricV]

Thanks guys. What got me thinking was looking at the first pic of Wickedwill's Kush (post #64 of link below.) To me they look similar, though the valleys of mine are wider. Anyway, don't want to mess up a new chain, so all the more reason to do it right. Thanks again.

http://www.cafehusky.com/threads/kush-sprockets-for-the-husky.34546/page-4

 

[Kyle Tarry]

Pointy teeth = done.

Try to lift the chain off the sprocket on the backside. I bet it comes nearly all the way off.

7k miles isn't too bad for sprocket life anyway, on an offroad bike.

 

[EricV]

Pointy teeth = done.

Try to lift the chain off the sprocket on the backside. I bet it comes nearly all the way off.

7k miles isn't too bad for sprocket life anyway, on an offroad bike.

Agreed. Yes, I did the "lift the chain" thing but not much lift/space, which surprised me and added to my wondering if I could slide by. I've ordered a new sprocket, so I'll ride it more this weekend and then, hopefully on Monday or Tuesday (when it arrives), change it all out. Thanks again for the input.

 

[Theo]

Here is the situation of my secondary drive, at about 9,300 miles mainly on asphalt:

8 links of the chain measure 5.016" instead of 5.000", so now it's 0.3% longer. I tired to set the caliper to 5.08" (+1.6%) and the 8 links were appreciably shorter.

So, IMO it's ok.

Some teeth of my front sprocket:

IMO they are ok.

Some teeth of my rear sprocket:

They don't seem good to me.

Many people say that if you replace only one of these three parts (in this case the rear sprocket), it will wear much more quickly. On the other hand, I don't want to throw away a good chain (which is the most expensive of the three parts).
Did you ever use a new sprocket with an old chain? Did it really wear more quickly?

 

[JonXX]

Chainwheels don't wear only in the forward/back axis, they also wear side to side, and the chain wears to match. I've see chains running at visible degrees of roll away from square - this is why chain alignment when making adjustments is important too. So changing one of the three elements that are "wear matched" to each other with an element that is freshly square will throw the whole wear schedule out of whack. That said - we've all replaced one element at a time due to lack of immediate budget (and paid more for it down the road).

 

[Theo]

Actually I'm not sure anymore about the replacement of that sprocket, because I've found out that it isn't so worn.
I've remembered that years ago I took some photos of it, because its bolts became loose and so, while I was riding, they dig a little forrow in the swingarm (which was fixed by a mechanic). Look at this:

My bike had not more than 2.5k miles and the teeth of the sprocket already looked pointed like they look now, therefore I guess that the sprocket was simply designed like that: it isn't worn.
Anyway, I agree about this:

Chainwheels don't wear only in the forward/back axis, they also wear side to side, and the chain wears to match.

because, as we can see in the photos I posted, the sprocket are clearly worn on their sides, especially at the bottom of their teeth. So, I think that the side wear of the chain is mainly in these areas of the inner links (I've coloured the outer side, but I mean the inner):

I've Always used my chain like that:

So, if I'm going to replace the sprockets without replacing the chain, I could overturn it, to use areas of the links which should not be worn:

 

[JonXX]

Yes you could flip your chain, that will wear the other side of the inner plates. But the side plates are not the only chain elements that wear, the rollers are also "wear matched" to the chainwheels. Let us know how it goes.