Vintage Dirt Bike Q & A

Anything and everything about Vintage Dirt Bikes! After you Register, email nathan@alp-sys.com and let me know so I can activate you.
It is currently Thu Mar 28, 2024 7:51 am

All times are UTC - 7 hours [ DST ]




Post new topic Reply to topic  [ 4 posts ] 
Author Message
 Post subject: MT 250 wiring diagram
PostPosted: Mon Jan 26, 2004 6:44 am 
Hi all, I just picked up a 75 MT250 for real cheap. Problem is that it doesnt run... definetly an electrical issue. All I have on the bike are the 5 wires coming out of the tranny and the coil with only one wire input. Everything else was stripped and im really confused. A wiring diagram or any other help would be very appreciated
Thanks


Top
  
 
PostPosted: Mon Jan 26, 2004 6:45 am 
OK I had the same deal with a MR175. Heres what I did. I ran a wire from the points to the coil. Sounds simple but it took me a long time to figure it out. Your stator plate should have 3 stator coils on it.Lighting,Charging ,and Ignition. You only need the Igition stator coil to start the bike. Mine measured 2.7 ohms with a digital multimeter when disconected from the points. Make sure the points are in good shape If in doubt replace. The stator coil wires go through a silicone rectifier.It acts as a voltage regulator and also converts AC to DC for the lights and battery. You dont need this to run the bike so bypass it incase its faulty and not letting any current through. The ignition coil under the tank has 2 sides . To check the primary side use a digital multi meter between the wire coming out of the coil and ground. It should be slightly less resistance then the Ignition stator coil. Mine measured 1.5 ohms. The secodary side should be up to 7000 ohms when measured from the spark plug cap to ground. The capacitors hardly ever go bad so dont worry about it right now. Check that the spark plug cap is making good contact with the spark plug. The spring was gone in mine and was the sourse of lots of greef. So to recap... A good stator coil has a wire that goes to the good,properly gapped points. Add another wire from the points to the good ignition coil. add a new spark plug and you should get spark. spark will look weak but they never had great spark to start with. Hope this helps...good luck.


Top
  
 
PostPosted: Mon Jan 26, 2004 6:46 am 
I just scanned and uploaded one. Enjoy.

http://www.sonic.net/ldavis/pics/mt250wiring.jpg


Top
  
 
PostPosted: Mon Jan 26, 2004 6:46 am 
Thanks for the diagram
Still confused though, what wires do i need to hook up in order to get a spark. It looks like just the black/white to the coil, but this doesnt make any sense.


Top
  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 4 posts ] 

All times are UTC - 7 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 44 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Group