Kawi2strokes.com Forum

Enthusiasts from around the world dedicated to the preservation and ritual flogging of the infamous Kawasaki 2-stroke Triples
It is currently Thu Jun 22, 2017 8:45 pm

All times are UTC - 5 hours




Post new topic Reply to topic  [ 4 posts ] 
Author Message
 Post subject: Yamaha dt400e
PostPosted: Wed Jun 14, 2017 2:08 am 

Joined: Sun Jan 22, 2012 7:23 pm
Posts: 93
Location: Central Coast NSW, AUSTRALIA.
Hi, just done a resto on a 78 dt400e. Full engine rebuild except top end which measures good. Am very familiar with mikuni carbs as I pretty much only do 70s 2 strokes. Bike will start second kick on choke, and fast idle. When I turn off choke engine tries to die, need to throttle up above 2k to stop stalling. Would expect it to be the carb but I have gone over that vm34ss numerous times. Timing seems exact, have gone just either side of the timing mark to test. No difference. Manual says float level 22.9 which of course I have, but +/- 2.5, so have tried all that. No difference. Saw a blog on another site, someone said identical problem, solved by new cdi. Manual cdi test you need special testers, can`t test it or the magneto and rotor. How likely is it to be the magneto as I am thinking the spark is only strong enough when revs are up, not below 2k? I have an opportunity to buy a stator/magneto local for about a ton which is reasonable and a lot quicker than getting from the states, but I am reluctant to just pot shot it. Any suggestions guys? Steve. (Australia).


Top
 Profile  
 
 Post subject: Re: Yamaha dt400e
PostPosted: Wed Jun 14, 2017 1:22 pm 
User avatar

Joined: Tue Jun 21, 2011 10:09 am
Posts: 490
Hallo mate! My DT400 had some issues, and one of them was the plug cap was causing a miss at high RPM. Not your problem, but something that happens. I would check the pilot jet very closely. With the choke on, the pilot jet is effectively bypassed. Once the choke is released, the pilot jet control idle conditions. If it is even partially clogged, it will cause problems. I know you have already cleaned the carb, but try it one more time. If you used an aftermarket carb kit...that may be your problem as those kits' jets are ALWAYS WRONG.


Lane


Top
 Profile  
 
 Post subject: Re: Yamaha dt400e
PostPosted: Fri Jun 16, 2017 4:20 pm 

Joined: Sun Jan 22, 2012 7:23 pm
Posts: 93
Location: Central Coast NSW, AUSTRALIA.
Yep I know about the inextactness of kit jets, and the pilot jet is 27.5 and totally clean as is the feeder hole. Had carby off maybe 25 times. Another site suggested the plug cap so I`ll go there, thanks.


Top
 Profile  
 
 Post subject: Re: Yamaha dt400e
PostPosted: Fri Jun 16, 2017 11:38 pm 
User avatar

Joined: Thu Jun 23, 2011 2:26 pm
Posts: 1658
Location: Running Springs Ca
I have used a strobe timing light to help diagnose a week low speed coil. Just a thought.


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

All times are UTC - 5 hours


Who is online

Users browsing this forum: No registered users


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

Jump to:  
Powered by phpBB® Forum Software © phpBB Group