I’m not sure you can turn (what is probably a viral) tickle cough into a (bacterial) pneumonia just through exertion. If anything, I’d think airflow would help. You might feel like crap but the alternative is to miss it completely? No brainier for me.
I’ve given myself pneumonia (too much time outside whilst already a little ill) and ended up in hospital.
Not sure a days bike riding with the right clothes would necessarily give you pneumonia, but TBH if it was going to make me feel even more crap, my chances of crashing would be higher (lack of oxygen and generally just not with it) and the cold is going to take even longer to shake off, I’d spend the day at home with a hot drink and a book!
Having said that, I find a good long ride sometimes acts as the ‘kill or cure’ to get over a stubborn cold that’s on it’s way out, presumably the further elevated body temp kicks it over the edge).
unless you are going down screaming STRAAVAAAA as loud as possible
Is there any other way?