recently aquired a TY250, complete with a TK carburetor.  Can anyone give me some background on the TK:  was it stock, is there a current equivalent, where do you get parts...OR, should I just go with a replacement?  Thanks.

TK carbs were used on some years of TY250.

 

Check with your local Yamaha dealer for spare parts.

Yes a TK carby was standard on the first model TY250. If it still in good condition, you will find it works very well. You can buy some parts through Yamaha dealers but they are usually very expensive. There are new carbies available if you need to replace it. Keihin, Mikuni, Dell Orto and OKO are popular choices

I still have the TK on mine and is running nice after 30 years of competition. I have looked a mikuni replacement later