I have had a seriously neglected DT125r in my extremely in-experienced, though very enthusiastic and keen to learn hands for a few months now, and have had technical help on a number of occasions already from experts on this site bringing it from a very sad state to the point I am now at. To date, I have cleaned the carb, changed the reeds, recovered the heavily sulphated battery, had 2 new keys cut, replaced all the fluids, cleaned out the tank and re-newed the fuel, bled the oil pump pipe, cleaned the air filter,

and now I have today tried to start it, and after kicking it over a few times finally got it to run, BUT, it only ran for a few minutes and then cut out?

Was not sure if I left the choke on for long enough or not? also tried the fuel tap in the "Fuel" and "Reserve" positions, tried it without choke, and then again with choke, left it for 10 - 15 minutes in case I had flooded it, and managed to get it started 2 - 3 more times before it again cut out? When I did manage the few times to get it running for a few minutes, on a couple of occasions it also "back fired"?

In the manual there is a multitude of possible causes, and I am prepared to work through them all if I have to, unless anyone can see there is something obvious I am doing wrong? or failing to do completely?

I would be most grateful for any pointers

Many thanks

Robbie

Could be anything Robbie but it sounds promising. Try getting your plug hot with a hot air gun, you will need some thick leather riggers gloves to handle it, re-fit it quickly and try again, remove the choke after around 30 secs and give it some revs.