Hi Guys, 
 
I have a DT125R (approx 1992) that I bought non running for use a s a field bike. 
 
I have put the bike together and now having problems starting. 
 
I had to replace the CDI unit which is now working fine, I have put in a new plug and get a good spark with the plug out (earthed properly!!) the compression in the piston is good. 
 
The exhast is fitted and so is the airbox/filter 
 
I noticed the original carb had a pilot screw missing so I replaced the carb with one that I have been told worked fine on the previous bike. 
 
When kicked over the bike will start but idles very slowly for about 10-15 revolutions then stops. 
 
I can get it to start again with another kick but if I give it any throttle at all it peters out. 
 
Push starting I get nothing at all and I definately have a good supply of fuel to the carb (I have an open ended plastic bowl/resevoir connected to the fuel pipe. I can see the fuel going down after a number of starts. 
 
I am unable to say what the crank seals are like howver there is a great deal of induction noise when kicked over. 
 
Any idea what the problem could be? I would be gratefull of any help, I have seen plenty of previous posts but nobody has posted replies to say what fixed it!!  
 
Any help is appreciated and thanks in advance. 
 
Regards, 
 
G