I brought this 88 YZ-250 back to life. Rebuilt EVERYTHING. 40mm square slide carb, pro circut pipe, boyesen reeds, Answer silencer.
The bike runs great, no flat spots, plug check comes out perfect. The problem is it takes AT LEAST 10 kicks to get the darn thing started. Tryed with the choke and it just floods it.
Can anyone give me some hits are where to start to look on getting this thing to start easier. I put about 3 good hours ride time on it this weekend and the starting didnt get any easier.

 

Float height and ignition timing are the first things that come to mind.

 

Thanks MWQ.....The float height is good, The timing is set at the stock setting, but I am goin gto set it with a dial indicator this weekend.
Does anyone know if there is a need to change the ignition timing due to the mods I have listed. I am thinking of advancing the timing a touch and see what that does for me (after I check the stock setting with the dial indicator)

 

Check the spark... A weak spark can wreak havoc in tuning an older two stroke. After that, I'd concentrate on the starting technique: three or four very slow kicks, get it on a downward stroke and jump on it. Even after sitting for months, this method can usually start my 250R's in one or two attempts.

 

where is your air screw at 1.5 to 1.75 turns out is usually good

 

Double check your compression .

 

Thank you for the advice. I figured the prob out about 2 days ago. The spark plug boot was screwed in crooked into the wire. It was only touching the core on a very small part which lead to the hard starting. It now starts 1 kick every time.