Copyright WWW.DBBP.COM | updated 29-July-2024


Project started October 2023,

 
 
 
After installing that 170/80-15" rear tire we found (ofcourse) that the chain would interfere so the sprockets would need to be offset. We did not want to widen the swingarm so we decided to leave the brakedrum where it was but to offset the sprocket on it. We removed all the 20 rivets using a sharp chisel and found that installing the sprocket on the other side of the mounting flange would give us 11 mm offset. Plenty! However, the sprocket ring would normally center on the mounting flange and in the new position it could not....

 
 
 

We decided to make a ring to center the sprocket. First we machined the inside of the sprocket ring round again, as it had little bumps where the rivets had been. Then we machined the outside of the brakedrum in the area we would be centering on. Finally we made a ring to fill up the gap and TIG welded that to the sprocket ring with bronze filler. Then we machined the inside of the ring that was welded into the sprocket to a super tight fit on the brakedrum.

 


 
 
 
 

We used the planishing hammer to install 20 new rivets and assembled everything back on the bike. Using this method the rear wheel is still in the center of the bike where it belongs, only the transmission will be offset 11 mm


Previous