Originally Posted by
datlas
Define “need new chain.”
I get 3000 miles/chain with not much maintenance, replace when elongated by 0.75% or so. Cassettes last longer, around 10K miles.
Me too. I don't get it!
I put on 8,000 miles between 2 cheap derailleur type drivetrains and never changed a chain or sprockets with minimal maintenance. Both worked fine when I gave them away. I didn't even know they wore out until I joined BF's. Ignorance is bliss!
That said, on my recent 2018 bike I brought in for service, they told me my chain was stretched or worn. I didn't measure it so I had them change it since it didn't cost much. I've been checking the new chain and at 1,400 km there is 0 stretching.
I'm sure drivetrain wear is highly dependent on total weight, conditions (hills, tough trails, etc.), rider power applied and proper operation of the drivetrain. Considering my 150 - 160 lbs, mostly flat roads and perhaps average power I suppose my results aren't too surprising.
I worked with a 280 lb man that rode one of those skinny tire road bikes about 15 km to work 5 or 6 days per week. He wore everything out on those bikes every year even on flat roads.