Rear Sprocket

I always thought, especially on older bikes with drum brakes, to have a rear sprocket that doubled as a brake would be the shit.
Solve a lot of headaches, why was this not done?
So I'm looking at the January '09 Easyrider, page 18 "The Parts Bike".
And damn there it is, a rear sprocket that doulbes as a rotor for the rear caliper.
Sweet.
Maybe this has been around awhile, this is the first time I saw it.
What do you think?

 

I've seen it done on custom choppers in the past. I assume the calipers will heat the sprocket up to the point where it may weaken the teeth of the sprocket maybe? Only my guess on why we don't see it more often on main stream bikes. I always thought it was a kill-two-birds-with-one-stone idea, but maybe there are more drawbacks then we know. Interesting concept however.

 

About the heat the sprocket was drilled.
Still I see your point.

 

Yes, I assume the driller sprocket would run a bit cooler. Still, there must be a reason why we haven't seen it on stock bikes yet.
A brake disc is pretty hard material to stand up to the friction of constant braking, so the sprocket would need to be made out of that same material (hard as hell)
Then there's the issue of chain lube getting on the brake pads/caliper which may be another consideration? I'm just thinking outloud - I guess the fabricators of this concept have taken all that stuff into consideration also.

 

It works (marginally) on my son's 5hp minibike but as far as on a real motorcycle... I think the chain lube VS. brake thing makes it wholly impractical as far as SELLING a bike to the public so equipped, can you imagine the lawsuit potential?

 

They have been available for a few years. I don't know how well they work. It looks like all the bikes they're on have oil less chains.They're around $500 here.

 

Seems like maybe a cost thing too, that sprocket is going to wear out pretty quickly, and I bet its not going to be cheap to replace