I put the choke on at idle and the engine shuts down.

SOURCE: bogs down at 25 30 mph 1st gear 45 in 2nd gear

• Check to see that the choke is not partially on.
• Drain the carbs and clean them with B12 chemtool or any other good carb cleaner. The main jets in the carbs are probably gummed up. To clean the carbs properly they will need to be removed from the bike. Be sure to balance and synchronize the carbs when reinstalling.
• Remove and clean the petcock water trap and clean the trap of water and rust etc. If a filter screen is present clean it as well.
• Set idle speed to factory specs. Do not use gas with Ethanol.

SOURCE: Starts then shuts off if put in gear

Check the side stand kill switch. It kills the engine so that you don’t start out with the side stand down. Broken or out of adjustment, it would make the bike die as soon as you put it in gear or release the clutch. Check for a broken wire at the switch or coupler. Get a service manual and check out the electrical section. Some bikes have a diode integrated into the turn signal relay. Try moving the kill switch by hand. If that doesn’t work then wire a jumper around the switch to bypass it. If that doesn’t work, check out the relay. Chances are that your '83 does not have the special relay.

Go to the site below where you can see a parts diagram for your specific bike. You will select the actual brand, year, model, etc., once you go to the site. Part numbers and prices are also shown. You can order parts from this site. In the event no price is shown on a particular part, the part is not in stock. www.babbittsonline.com/pages/parts/viewbybrandand/parts.aspx

Check out the tab "ELECTRICAL 2" at the bottom of the diagram, item #15. Babbit's has them in stock, $60.00. I don't get paid for my answers but I do take pride in them, and I am only trying to help. So if you will, > > A “very helpful” rating for this answer? Thanks!

SOURCE: My ttr 125 will start

The jetting is fine as is. The carb just needs to be cleaned. The pilot jet especially and the related circuit as well. Go to the website below and you can see an exploded view of your carb. Please rate my answer. Thanks.
www.babbittsonline.com/pages/parts/viewbybrand/default.aspx