Changing fork on my marin

trow said:

I have an older Marin mountain bike (bobcat trail). I would like to put a suspension fork on it. It has a threaded neck. I just started mountain biking have always ben a roadie. Was wondering If I can still by a good fork for it and some ideas on what to buy to get started with. Also can it be converted over to a threadless neck.

Is it 1-1/8"?
If it is, you can select from a wide choice and forks.
However, if it isn't 1-1/8" you will be severely limited in choice.
It is easy to put in a threadless headset in place of a threaded one.
You might find a market for your old Marin Bobcat Trail if you don't want to keep it. Since geometry is part of the design when making the bicycle for suspension, you might be better off starting over. Just one item that I note can be a major concern is stand-over height with a suspension fork.

I have done just that 2 years ago with my old steel Bobcat (ca 1995). Used threadless 1 1/8" Manitou Axel Elite with a generic threadless headset and steam. You will also need V-brakes (or at least one at the front) and a brake lever with a long pull. To keep your position on the bike (with a suspension fork the front end gonna be higher) you may consider to lower the handlebar by using fewer spacers.

Best luck

Dimitiy