300/440/550 WTB JS400 coupler

[kaduka]

Looking for a JS400 coupler

 

[twisterad3]

I know this is an old thread.. but out of curiosity, is the 400's the steal coupler?

 

[restosud]

cast iron coupler.very early ones had 4 prongs only.

 

[twisterad3]

Nice. I have the 6 finger cast iron ones. What was the benefits of the cast ones over the newer style?

 

[restosud]

newer are aluminum and thread on the crank. but all full circle crank couplers where cast iron with pressed on stainless seal wear ring and are bolted to the crank with a taper fit .
the aftermarket made them out of alloy.