Maintenance & Check Up on a Used KX 125

[MXonaKawi]

In addition to buying and replacing old parts with tons of goodies on my bike, I think it's necessary to get the bike checked out properly before it's first ride.

It is a Used 2000 KX 125

I have completely disassembled the bike into pieces. I have drained the oil, drained the gas tank and radiators.

I bought new radiators. What type of coolant should I used for the bike?

Also, what type of brake fluid should I use for the bike?

What type of motor oil should i use for the bike? And is it ok to keep the engine sitting here without oil in it? Does it need to be flushed before I add new oil?

I plan on getting anew gas tank and using a new pre-mix probably Klotz or Maxima 927. Haven't decided yet. Is there anything I need to do to the bike when switching to a new pre-mix?

I plan on getting new v force reed system to replace the stock one and a new pro circuit pipe and silencer combo. Do I need to do anything else besides change the jetting?

Also, should I have the suspension & engine checked out? What should I have done to it? I'm really good at picking out cool performance and aesthetic parts but after 10 years away from the sport, I have a lot to relearn about the important parts and how to work on and maintain them.

[MXonaKawi]

Any input?

[sandblaster]

Wow MXonaKawi, a person could write a book on the questions you asked 
They are all good questions but a lot of them are open to personal opinions.
Do you have a Clymer manual for it?
If not, get one as it will pay for itself many times over.
Let me take them one at a time.

Also, what type of brake fluid should I use for the bike?
Personal opinion.... Dot 3 or Dot 4. Both have worked good for me over the years.
I am currently using Dot 4

What type of motor oil should i use for the bike?
What ever it is, use a high quality oil and change it often.

And is it ok to keep the engine sitting here without oil in it?
Depends on the conditions.
If it's kept dry and out of the weather it should be good for a while.
I do like to keep clean oil in mine.

Does it need to be flushed before I add new oil?
Certainly wouldn't hurt.
I would even consider removing the clutch cover and clutch asy so I could clean the clutch asy and pre lube it before I ran it.

I plan on getting a new gas tank and using a new pre-mix probably Klotz or Maxima 927. Haven't decided yet. Is there anything I need to do to the bike when switching to a new pre-mix?
Watch your plug color and dial in your jetting.

I've got to go so I'll let someone else blow my comments into the weeds   

[MXonaKawi]

Sandblaster thanks so much for the heaps of great info you have given me since joining. I do not have the clymer manual but I did download a pdf of the kawasaki owners manual.

I am planning on using all maxima products for all oils, lubes etc. with the exception maybe running klotz for my fuel.

I will definitely flush it and clean it all out and get some clean oil in there asap.