Extreme chain stretch on Duke390

[Asymptomatic]

Hey guys, quick question. Never dealt with this before. The chain on my bike gets loose enough to slap the swing arm after 500km. I adjust it and within another 500km is loose again. How could the chain have so much stretch? The links don't feel loose and the chain still looks new. What gives?

[TexasAggie]

I had a similar experience with a cheap chain on a 650 Honda. It stretched for 1000 miles then was OK until I noticed it was eating the sprockets at 3000 miles. It looked good but was out of spec quickly. Tighten and keep an eye on the sprockets.


I also had an old Bultaco that the axle nut was running out of thread and did not really tighten the axle as it should have resulting in constant need to adjust for chain tension.