Motorcycle Repair: Timing chain replacement on a xr75, honda xr75, timing chain replacement

Question
i have a 1977 honda xr75 that the timing chain came off of and broke the cam sprocket. i replaced the cam sprocket but the chain is stretched enough that it keeps comming off. ive tightened the tensioner as much as i can but still the chain comes off. is there a way to replace the timing chain without splitting the engine and pulling the crank? also is the crank sprocket replaceable or do you have to change the crank?

Answer
Hi Kelly,

Q:  "...is there a way to replace the timing chain without splitting the engine and pulling the crank?"

A: Negative


Q:  "...also is the crank sprocket replaceable or do you have to change the crank?"

A:  The crank must be replaced.


Respectfully,
Mark SHively