Is This A Wind-Up?
 

OK. After all the fretting about getting my front sprocket off and the tales of other peoples troubles plus predictions of how difficult it would be without having a chain attached, I went out and spent money on a 2 foot long breaker bar and a 32mm deep socket.

I put the bike in first gear and the thing came off with no bother! No need for wrapping a chain on or wood through the rear wheel, it came off with 1 good tug while in 1st gear.

It's not in terrible condition, maybe some slight curling at the tips, I figure with a replacement being the fraction of the cost of the chain I may as well do them both.

http://www.curium.org.uk/images/misc/oldsprocket.jpg

Hopefully my chain riveter will turn up on Monday and I can finish the job up.

Here's the replacement sprocket that arrived.

http://www.curium.org.uk/images/misc/newsprocket.jpg

I think it's more of the front sprocket CAN take some persuading to come loose. There have also been folk reporting that the damn thing just fell off almost :shock:

You going for the stock gearing or maybe a tooth extra or less?

Stock gearing. Only changing them because the chain snapped. New chain was almost a ton so I figure 'why skimp on the sprockets?'

Anyone know if I can slap on bog standard 'nut-lock' from Halfords or do we need special stuff?

Also can anyone advise on what grease to use and where?

I'd never looked under the sprocket cover previously, but now i have Ireckon I'll clean it all up with a parafin soaked brush. Just want to know if there's any reason I shouldn't do that?

Those teeth look pretty worn to me. They're not particularly hooked but there's a lot less meat there than a new one.

As for the new one, if that part number means it's a 520 size, are you sure your chain is a 520, the standard chain is a 525. The difference is that a 520 is 1/4" thickness sprockets, a 525 is 5/16". :?

There's not a huge difference in strength but the 520 will probably wear faster, and you definitely shouldn't run a 525 chain on a 520 sprocket.

Christ! You made me crap myself for an instant.

I just checked the jtsprockets web site and they say it is for a 525 chain (which is what I have purchased). I agree that the nomenclature is confusing.

http://www.curium.org.uk/images/misc/jtsprockets.jpg

You reckon? I haven't open the new one so can't compare yet but I will.

phew!

someone sack the guy in charge of part numbers! :twisted:

Looks worn to me. The give away is the squaring off at the base of the tooth.
I always replace sprokets with the chain. As you say a chain costs a fortune, but the sprokets are pennies.

I'm thinking of dropping a tooth off the front, to lower the gearing on my Faired 2000 SV (carbed). I want the extra acelleration, but I'm interested to know how much top end is knocked off. Current top speed is about 130-135 on the speedo, with 140 coming up once with a tailwind.

Dan.

Just noticed that the old sprocket is wider then the replacment. The teeth section look the same width but the total body width is bigger.

Is this going to be a problem?

Dan the gear ratio will be 3.14

the pic is not that easy to check, but it looks like it's an original fitment with the rubber damper rings on each side.

These are purely to quieten the noise, nothing else. Aftermarket sprockets usually don't have these, it's no problem.

As long as the thickness of the teeth is the same it'll be fine. The sprocket should have a small amount of side clearance in the chain, somewhere round 0.5mm (I haven't checked the actual dimensions according to the manufacturers but it's in that parish)