"The Sears"

by Old Iron Rider

Monday, August 9, 2010

Custom sprockets...

As I'm waiting for parts to arrive from Matt, I figured this was a good time to tackle the special sprocket shafts that the Spacke's used... You can't use a simple sprocket like a Harley or Indian. Spacke made their sprockets part of an oil retaining keyed shaft... This pic below shows an original one on the left, and the new one on the right.  I did not make these as I have neither the talent or machinery. But I do know a great machine. shop.

You can see the worn sprocket on the left that was good enough to get me a block or two on the Cannonball... These sprockets were made from Martin commercial blanks.    The process requires a machined shaft with a slight taper on the inside.  You next need to broach a keyway to lock it onto the drive shaft....
The pic below show that the rear of the sprocket shaft has three groved cuts in it. This area holds hemp like material that will soak up oil and hold it in case, and let a lil wick out....

Once the shaft is made, then the sprocket must be cut to fit, welded on and once true, they need to be cut to the 520 chain size.... An amazing process to say the least....     I got one made OEM size of 14 links, and another with 13 for a little extra power when climbing mountains.  
Next up...a look at the front wheel, the "scrub brake" and fender....


1 comment:

  1. Looks like someones got one hell of a straight entry line here...
    Good for you!

    ReplyDelete