facebook1 youtube1 twitter1 instagram google plus linkedin1 pinterest1

logosmallNOTICE:  If you are not a free registered member of the site, you will not see the photos in the forum, and you won't be able to access our premium member content. Please consider joining our community!

Welcome, Guest
Username: Password: Remember me
  • Page:
  • 1

TOPIC: 1974 DT250 Ignition Issues

1974 DT250 Ignition Issues 25 May 2019 01:12 #1

  • Efeuguertel
  • Efeuguertel's Avatar Topic Author
  • Offline
  • Newbie
  • Newbie
  • Posts: 1
  • Likes received: 0
Hey all,

My DT250 has me banging my head against the wall. It does not start with a kick, until I spray starter fluid into the carb, and then it fires up and the headlight comes on. It runs amazingly for about five minutes, and then I start to lose power, the headlight dims and dies, and the motor dies. I kick and kick, no start. But at that point, I can roll start it and get it moving again, but then this all happens about every 45 seconds after that.

I just want to hit the trail with it! Does this sound familiar to anyone?

Please Log in or Create an account to join the conversation.

1974 DT250 Ignition Issues 25 May 2019 11:07 #2

  • Mothersbaugh
  • Mothersbaugh's Avatar
  • Offline
  • Collector
  • Collector
  • Posts: 1159
  • Likes received: 555
My first guess is that you are getting too little gas flow into the carb. You kick and kick and kick, and then just as the carb bowl is about full enough to start, you stop kicking and spray starter fluid into it, and Voila...it starts. Then it starves for gas after a short while, and this time around, you kick and kick and kick while the bowl refills at a very slow rate, and then just as it's about ready to start by kicking, you give up and try roll starting it instead. And Voila...it starts...only to drain the bowl again. It's like the old algebra problems where if one valve can drain a tank in 4 minutes, and it takes another valve 5 minutes to fill it, how long does it take to fill the tank if both are left open?
Take the gas line off at the carb and see what kind of flow you have. Could have a screen full of crap where the petcock screen sticks up into the gas tank, or you could have passageways blocked in the petcock valve. Quick thought...have you tried RESERVE instead of ON to see if that gets you better flow? Sometimes one route through the petcock clogs while another stays relatively clear. But check the flow first, and then if you need to, drain the tank and work the petcock over.
The following user(s) Liked this Post: MarkT, RT325

Please Log in or Create an account to join the conversation.

Last Edit: by Mothersbaugh.

1974 DT250 Ignition Issues 26 May 2019 02:20 #3

  • RT325
  • RT325's Avatar
  • Offline
  • Collector
  • Collector
  • Posts: 3917
  • Likes received: 1265
Yep endorse everything above & have you had the carb off yet plus is the choke working or is the idle set very high to just hope it'll keep running but this could effect the choke operation although would have to be very high to stop the choke sucking. Also for choke to work for starting throttle must be shut. But will richen the mixture somewhat when motor up & running with throttle up a bit if you wanted to just to prove a point that it's working. Confusing myself now lol.

Please Log in or Create an account to join the conversation.

  • Page:
  • 1
Moderators: DEETDevinDmanEnduronutMakotosunVinnieyamadminJames Hart