Does rear sprocket thickness matter?!?

I am trying to find a rear 38T sprocket for my DRZ that will hold up better than the alloy ones.

During the search I came across this thread about sprocket thickness: http://www.thumpertalk.com/forum/showthread.php?t=32877&highlight=sidewinder+thin

I can understand why a sprocket made of a lighter/softer material would be wider and why one made of a harder/heavier material would be thinner but I am wondering about the consequences of the increased lateral play if any.

The stocker is about 6mm thick and so is the Sprocket Specialist alloy I have now.

I have a 41T steel Sunstar on hand that is about 5mm thick and according to the thread above so is the Sidewinder Ti.

Does anyone have any insight on the subject? Does the increased lateral play cause faster chain/sprocket wear? I have quite a few more horses to pass along the drivetrain than a stock engine so I'm looking for something that can take some heat :thumbsup:

You can 'get away with' a steel sprocket that is undersized in width slightly. I would not use any alloy one that was not full width.

Basically, you are applying all your power to the first few teeth of engagement as the sprocket rotates. The greater a contact patch you have, the less stress. I have seen alloy ones 'mushroom' slightly where the rollers hit, a sure sign of more power than the sprocket can handle. Ideally, you want a sprocket the same width as the chain rollers.

William, have you ever used the Sidewinder Ti? It goes for an astronomical $130 but I can buy one for about the same price as a rear alloy sprocket.

I am tempted to give it a try but the thickness issue had me thinking twice about it.

Then again, they say it harder than steel but it's only 4.83mm wide while the plates on DID chain are 6.4mm apart.

That's a big gap that had me concerned for the chain even more than the sprocket...

No, no personal experience with the Sidewinder. To be honest, I'd be surprised if you get more life out of it than a stocker.

Here are some rambling thoughts.

It will wear, perhaps slower than a stocker but as you know, sprockets and chains should be changed as a set. Let's say the rear sprocket wears half as fast as a stock one. At some point, the CS sprocket and chain will be shot, the rear, half worn out. As soon as you put a new chain and Cs sprockwet on, they will wear very quickly as the rear is no longer has 'new' shaped teeth, they will all wear to match. So in a few hundred miles, your new chain and CS will be half way worn out already. That all said, it is possible the Ti sprocket being narrower may have the same longevity as a full width steel one. But Being narrowed, having less contact patch with the chain rollers could have abnoral wear issues with the chain.

Running on the street, I have no issues with alloy or an unobtainium sprocket to save unsprung weight. On dirt, steel is the only way to go.

Personally, I'd run steel unless I was a racer.

You can actually run a 525 or 530 chain on 520 sprockets. Looks goofy but it works if there is clearance for the chain. No good reason to do it, just an example. I would not worry about sprocket width as long as it is sold for use with 520 chain. The extra clearance lets dirt out without maching all the relief sots like some sprockets.

I wish I could go with something as strong as the OEM sprocket but unfortunately the choice of material in 38T is limited.

All the ones I have found are aluminum based except for the unobtainium made by Sidewinder -they also offer a tool steel but it's nearly as expensive!

JT offers a steel one though, but it's a 39T, so the choice is between 39T steel or 38T uber expensive unobtainium :thumbsup:

If someone knows of a manufacturer selling a 38T steel sprocket, please let me know!

AFAM 38T is alloy and so is the Sprocket Specialist, Sunstar does not make anything less than 41T, same for Stealth...

Did you speak to Norm over at Driven? Tell him I sent you.

What front are you running? Maybe the real answer is to jump up in the front to a 16 and not go so low on the back.

Edit - also, one tooth in the back isn't much of a change at all.

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