I built up a bike, based on a rigid 92 Hahanna frame, using all parts out of my bit boxes and only bought a doofer to singlespeed it.
The intention was to use it through the winter 2yrs ago but I use it for at least 3/4’s of my riding and absolutely love it.
The problem is I keep having the desire to “improve” it, replace STX V’s with XTR, lighter wheels, etc BUT it isn’t financially worth it and I worry it would ruin the character.
Then I think of building a new and improved version but have the same concerns.

Wait until bits break and then replace with better ones

Leave it as it is til parts wear out. Cheap bikes are ace. I have a singlespeed Hahanna too and it does ride nice. It’s just too small for me.

Old konas are always worth it

keep it as it is, maybe sourcing some parts as they turn up, maybe in the classifieds. I think part of the charm of useble retro bikes ( as opposed to ( mint restored used ones )is the fact they have a character and an assortment of odd bits, that just work well.If they don’t work well maybe replace bits.

You can’t polish a tu£d, but you can roll it in glitter

That’s no turd dood.

Wait til stuff breaks.

You can’t polish a tu£d, but you can roll it in glitter

I like that.

OP, leave it as it is. If you start adding expensive bits un-necessarily it’ll lose it’s character, plus you won’t be quite so happy to leave it unlocked outside the shop while you nip in for a pint of milk.

Err. If some thing doesn’t work well enough then replace I with something better

If its fine then leave it

Do you like the current brakes? If they don’t work well (with new blocks and cables) then buy some new one)

It’s not a turd if you’re riding it.

A b£inged up Ti bike that you aren’t riding because you prefer your other bike is a turd though.

My commuter bike(former mtb) is an eight year old Inbred. Not that I’d call it a turd, but it isn’t pretty looking but works flawlessly and is maintained constantly. Having once stripped the paint off and let it get rusty I slapped some rubbish ‘straight on rust’ paint on it with a brush!
I guess that’s smearing a turd in turd?
I’ve started to feel a bit guilty and will give it a proper paint job soon.

So if it’s your main bike it ain’t a turd so give it some love.