BE CAREFUL painting the seat post. In fact, I would simply clean it off with some steel wool and be done with it. Painting it is a good way of getting it stuck in the frame. (And the paint job will be ruined by the seat moving around and being clamped on anyway.) As for the bolts, if you can spare a few $, go to your local hardware store and replace them with stainless and never worry about it again.

I'm not sure about anybody else, but I don't generally put lock tight on any of the bolts on my bike and none of them have ever come undone. Whatever you do, don't use the red stuff.

The red stuff is OK; you just have to heat the parts to undo them (a hair dryer will do the job).

The rust on that stem is likely the result of sweat dripping off your face while riding...

Yeah, don't paint the seatpost either. Wire brush to remove rust, and a nice coat of grease (reapplied as necessary) will keep it from rusting in the future. Or switch to aluminium, which will save a bit of weight and won't rust (but you should still keep it greased) for 10 or 15 $.

Thanks guys. It is good to know.

Do you know where I can buy these? I don't my local bike shop has there.

Pyramid Brake Yoke Hanger Chrome Plated

This thought. Retire the old steed and move on to something you'll really enjoy riding. I'm not sure what motivated the Diamondback purchase but it wasn't a big investment. It would make a nice donation bike, IMHO. Unless you're opposed to the idea of a new bike.

thanks!

What is wrong with Diamondback bike?

I don't understand. I use naval jelly to remove the rusts from the bolts, and the rusts keep coming back.

Don't think I'm obsessed with this old bicycle. I just bought the new one!

If iron or steel is exposed to water and air, it'll rust. After removing rust, you need to seal any bare metal away from those elements using paint, wax, grease, or whatever to prevent new rust from forming.

Chrome or zinc plating is often used to prevent rust on bolts or fasteners. If that playing is compromised, the bolt will rust. You can paint or wax the bolts to prevent or slow down rust, or you can replace the bolts with ones that won't rust. (Stainless steel is one option, or you can use bolts with zinc or chrome plating that's intact - not scratched, chipped, or pitted.)

Nothing, but you aren't riding it much by your own admission. I just thought you might want to ride more if you really liked your bike, which you obviously don't.

If you're a very casual rider, you dabble once every few years or so. If that sounds like you, then I agree you probably already have the right bike. But if you'd like to really enjoy riding on pavement, then get a bike that is lighter, has precise handling, and will roll more smoothly than your old Diamondback.

No offence to Diamondback meant, they make all sorts of good and exceptionally good bikes.

I have not ridden it for a very long time. It was stored in the garage for so many years collecting dust. Ever since my dog passsed away, I decided to go back riding the the bike. Beside, the rusts were there after several months when I first riding this bike. I'm worried the rusts the may get in the new bike as well, so I'm messing with my old one.

Got it. Thanks.

There's a pecking order among metals where it comes to bike components. Parts that rust are near the bottom of the pecking order which ensures that spending a bit more on a bike gets one less likely to show the steel rust spots you've highlighted.

PS Sorry about your dog. :-(