1977 125 chain size

[Steve Minor]

Just want to verify chain size of a 1977 125 project bike. My parts manual calls for a 5/8 x 1/4 which equates to a size 520. It doesn't state the number of links. Can someone suggest a starting point? As a test, I draped a 428x132 link chain across the sprockets and thru the tensioner and it's way short. I looked at Dennis Kirk and the longest DID 520 standard chain listed is 130 links. Any suggestions?

Steve Minor

[Larry Perkins]

It takes less 520 links to get the distance.  130 is definitely enough but will need cutting.  I would think even 120 would be fine but it has been a long time since I did one of those.

Larry P

[Steve Minor]

Thanks Larry...I also got a personal email from Randy Brown confirming that a 130 link 520 worked on his 12/52 geared MC5. It was actually a bit long and needed a few links removed.

Steve Minor

[skiracer]

My MC5 250 has a 54/12 setup and my 520 chain is 106 links....

1976 MC 5 Original Owner
1976 Penton 175 XC
1985 20' Hi Point trailer