Mechanical chronograph

[speedking31]

If you have a mechanical watch with chronograph function, and you have the chronograph running, does it reduce the time the watch will run for? Or is it driven from the same mechanism so makes little difference? Is it a significant effect, i.e. a watch that runs for 72 hours would only go for 36 hours with chrono functioning?

[L1OFF]

speedking31 said:

If you have a mechanical watch with chronograph function, and you have the chronograph running, does it reduce the time the watch will run for? Or is it driven from the same mechanism so makes little difference? Is it a significant effect, i.e. a watch that runs for 72 hours would only go for 36 hours with chrono functioning?

I have a speedy pro which for the past 25 years I mostly had the chrono engaged when wearing it. I didn't really notice any difference in running time with chrono or without. I was however told by the chap who recently serviced the watch that it would increase wear on some parts (I didn't have any issues without a service for 25 years until the main spring needed replacing).