RE: Can´t get spark

76 Yamaha DT 400 discussion forum:


RE: Can´t get spark

RE: Can´t get spark 
Paul Lastrucci said 2007-04-02 16:05 
 
Hi there, New to this discussion I reside in Pretoria South Africa and have a keen interest in Yamaha 2 stroke scramblers of the seventies. I have restored to original a 1976 Yamaha DT400c

If it is a 1976 DT 400 ( Engine # Prefix will be 501-XXXX it will have a CDI breakerless ignition, no points only the DT 250´ had points and later that changed in 1977 to breakerless as well. You do not need a battery to run these bikes at all, same goes for a Points equipped DT 250. If you got no spark then you have to check all the related components. The dealers even today will most probably find a loose earth and charge you for a new CDI, It´s very important to ensure that the earth, earths properly and are tight.

It´s worth going through the process yourself. I suggest you get a manual and start measuring continuity and resistance of all the coils, The CDI charge coil (the one mounted on the backing plate to the right if you are looking at the backing plate in situ referencing the front of the bike) Lighting Coil (1) the one opposite the CDI charge coil to the left as explained above, the lighting coil (2) the thin one mounted on top of the CDI charge coil The CDI pulser coil (the black box mounted in the 12h00 position in the middle/top of the backing plate. Check also the ignition coil resistance and the condition of the suppressor cap and finally the spark plug. I´ll has it a guess that it is not the CDI unit that is the problem. These are robust pieces of equipment. I have all the resistance values if you need them.

Regards
Paul 
 
<<Previous          Answer          Discussion overview          Report spam          Next>>

Comments, questions and answersEnter a comment or answer to this message

You can post your question, answer or comment as a guest. Or enter your e-mail to join the forum and get notifcations of new messages.

 
Title 		 
Signature
Optional e-mail
Enter your e-mail to join the forum and get notification of answers and new messages. You can unsubscribe with a single click. Bikez does not display, sell or misuse e-mail addresses.
Message text

Describe technical issues in detail to get quality answers. You can offer or request second-hand parts and equipment as a privat person. Bikez reserves the right to remove any improper or commercial content.
Accept that we store and display the message.  

 

More 1976 Yamaha DT 400 information

Our discussion forums are intended for short messages. We also welcome more extensive motorcycle reviews.

Bikez also recommends that you check out the technical data and the riders' rating for the 76 Yamaha DT 400. You can also rate it yourself. Use our efficient motorcycle classifieds to sell or buy this bike. Your motorbike gets a high quality presentation. Ads are free.