You must be ultra fit, can maintain TT bike aero position all the way ! Damn! You must take part in Olympic races!

if you pedalling then got sound it could be pedal or Bottom Braket.
If no pedal but rolling got sound it could be hub or brakes.
if not moving also got sound, run fast, it is ghost month now.

As long as you are happy. U like Foldies, stick to Foldies, if you think RB better, go RB… If both you like, get both… no need ask for opinion wan. Unless not your money, than you ask the one who is paying.

How long do you consider long distance?

i started off with folding bike, ended up buying road bike after a while...

get a proper bike fit, ur bike and u will became best workout without any problem.

i starting up with fb, after add on few fb i bought a rb, change 2 rb frame coz size dont fit and maintain only one untill now. my friend always mad at me if i bring my rb when cycling together with them (mostly they all rb). they said i like to bully them if i bring rb. so my rb only store at home most of the time. i will ride my rb when i had to cycle with extreme rider group.

i can follow them up with my fb with no problem if the pace 35kmj and below with 100km+. fb is good for training ur cadence and build up endurance before jump to rb.

oh ya, all of my bike (6 fb 1 rb) already done bike fitting to make sure i didnt have any injury during cycling and i can go many milage without any problem.

this is my small piece of advice (actually my 10cent only)

buy rb when u can maintain 35kmj and above pace for 160km+. below than that, fb can do the same like rb. and if u already crazy about rb, the cost upgrading ur rb sometimes can buy u a car!

don't get me wrong, a folding bike can go the same distance at same speed like road bike just that you will have to pedal harder. same cadence same power output always a roadbike will be faster.
I go with roadbike due to the speed. i really do not have the time and power to go distance on a folding bike. with same effort i can go further or i can go same distance like folding bike with less effort.

Why are we talking about folding and speed???

Each bike has its own advantage... no one is dumb enough to say a RB can go mountain biking... good luck getting fall off....

Each bike has their own advantage.... and we choose the bike based on our needs... A folding is versatile to bring into public transport anytime... good luck getting a RB into MRT/LRT during peak hrs....

I bought a folding cause I live in apartment... space is a premium and I fold up the foldie to put into my car boot... try that with a mountain without a rack...

for Foldie people did endurance in it... it will be around 25-30kp/h sustain... which is OK for a bike...

if you want competition go buy a RM100K road bike

My latest setup