Adventure Motorcycle Magazine Subscribe Now

Results 1 to 2 of 2
  1. #1 Help Needed df250rtb 
    C-Moto Noob
    Join Date
    Jul 2019
    Location
    Tennessee
    Posts
    2
    First time poster out of desperation. Picked up this project and love the bike. It sat in the weather for some time by previous owner and I’ve had to repair or replace a lot on the bike.

    Old carb was eroded too bad to repair so I replaced it. New spark plug, coated fuel tank, new filter and lines, etc. It starts right up, idles like new, revs to half throttle great. After installing and adjusting a new clutch cable it shifts great through the gears.

    Problem: it has a terrible miss above about half throttle. Maybe 4K rpms (guessing). If I shift when it starts to miss I can roll into fifth and it will go about 40-43mph and that’s it, it’s just sputtering and popping. Back down to 38moh and I could ride all day with no sputtering and popping. New carb, float seems to be set right, air screw adjust makes no improvement at all. Thought maybe valve adjustment. The exhaust valve was tight so I set it to slide .006 and hold .008. Seemed to smooth the idle a tad but made no difference in misfire or backfire. I’m at a loss, don’t know where to look next. Shooting from the hip maybe: coil, stator, cdi? Maybe burnt valve, but I don’t really know how to check or diagnose? Any ideas? Here’s a video:
    https://m.youtube.com/watch?v=9oG1mL...ature=youtu.be
    Reply With Quote  
     

  2. #2 Re: Help Needed df250rtb 
    C-Moto Noob
    Join Date
    Jul 2019
    Location
    Tennessee
    Posts
    2
    Guy on chinariders recommended to start with the rectifier. Can’t believe it, but that fixed it. I’ll order me a spare. Hope this helps someone.
    Reply With Quote  
     

Similar Threads

  1. df250rtb
    By jawnee in forum Maintenance
    Replies: 4
    Last Post: 09-20-2013, 03:29 AM
  2. My DF250RTB
    By evokid8 in forum Street
    Replies: 34
    Last Post: 11-19-2012, 12:26 AM
  3. Help needed please
    By herbDR in forum Maintenance
    Replies: 7
    Last Post: 08-11-2012, 07:34 AM
  4. Custom DF250RTB build up
    By BellaCorse in forum Street
    Replies: 49
    Last Post: 08-02-2012, 05:07 AM
  5. DF250RTB Chopper
    By Loserland in forum Street
    Replies: 15
    Last Post: 08-29-2011, 10:55 PM
Bookmarks
Bookmarks
Posting Permissions
  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •