Hitchcocks Forum

Hi all, I need to down gauge my chain size (530) for a narrower chain (520), (special build bike / bullet gearbox), can anyone tell me what gauge sprocket the model g used and if it fits the bullet box. Also what sizes are available?

Thanks for your help.
Ian W

Follow up on the chain / sprocket size needed.


520 (5/8" x 1/4") which is 3mm narrower than the 530 (5/8" x 3/8")

If I can get a gearbox sprocket to suit then it looks like I'm sorted.

Is the model g 5/8" x 1/4"?

Should be easy enough to find someone to face off a standard sprocket to the narrower dimension on a lathe, I don't expect Indian material will be very hard! You would only need to turn down just below the teeth and you could choose one side or the other - or a bit off each side, in order to get the chain run you need.

That's a very good idea, thank you.

But the wallies down here will charge more for the metal work than one would cost from new.

Why not use an angle grinder and do it your self. The tollerances are not very tight.

Yes could do, may have to if they dont make a 520. I need sprockets for my other bikes anyway so I may as well get the right thing if it is available.