bad cdi?(95 yz250)


9 replies to this topic
  • jebova2301

Posted July 12, 2010 - 12:45 AM

#1

my bike had been getting progressively harder to start. once it started, it would run fine. it had gotten to the point where it didnt want to start. i figured it needed a new top end. replaced that. still have the same problem. replaced the spark plug. same problem still. think i may have a clogged carb. after cleaning and checking my jetting to be sure i had it all according to my notes, it still wont start. now im thinking its something electrical. i checked the stator and coil with a multimeter, and the coil was reading a tiny bit high on the primary resistance(.4 ohms and the manual says .2-.3). ordered a new coil just to be sure. the stator was dead in the middle of the manual specs. do you guys think i should just go ahead and replace the cdi box and see if that solves it? or is this even a symptom of a bad cdi? or what other thoughts do you have? i am open to anything aside from calling it a loss.

  • jebova2301

Posted July 12, 2010 - 10:20 AM

#2

anybody? and another question...how do i bypass the engine stop switch on the bars? what wires do i need to bridge to do that?

  • ace402

Posted July 12, 2010 - 10:24 AM

#3

I think I have a CDI off of a 1992. You could try that one for just the cost of shipping. Does anybody know if that would work? It may be the CDI, but generally when it is that the bike will start fine then die when it warms up.

  • jebova2301

Posted July 12, 2010 - 11:56 AM

#4

I think I have a CDI off of a 1992. You could try that one for just the cost of shipping. Does anybody know if that would work? It may be the CDI, but generally when it is that the bike will start fine then die when it warms up.


well...i decided to RTFM and figured out how to test the stop switch. it was a bit finicky, but would err on the side of not being able to shut the bike off rather than not let it run.

if you do have that cdi box, i think i may take you up on that offer. even if it ends up costing like 15 bucks more if it is bad, i save a lot if it isnt the problem

  • jebova2301

Posted July 12, 2010 - 11:59 AM

#5

actually, after doing more checking, it doesnt look like it will fit.

  • arnego2

Posted July 12, 2010 - 04:46 PM

#6

Hi there
have you tried contact spray and cleaning those connectors? Works wonder once those contacts are clean. :smirk:

regards
Arnego2

  • jebova2301

Posted July 12, 2010 - 06:08 PM

#7

Hi there
have you tried contact spray and cleaning those connectors? Works wonder once those contacts are clean. :smirk:

regards
Arnego2


which contacts? i used a wire brush to take all the paint off the frame where the coil mounts. the coil is new, so it should be no problem. i cut all the bullet plugs off the harness and replaced them with brand new ones, and then i also did the same thing with the little screw thing that mounts on the coil. the only thing that i havent done is check the actual inside of the stator and the timing. i plan on ordering a dial gauge tomorrow to check the timing

  • jebova2301

Posted July 12, 2010 - 06:32 PM

#8

also guys, i want to thank you all for being patient with me. if i get a bit snippy, please dont take it personally. i am just getting pissed at the bike. thank you for all the help

  • MarkBYZ250

Posted July 12, 2010 - 09:24 PM

#9

Someone correct me if i'm wrong but the kill switch could be a problem.

  • jebova2301

Posted July 12, 2010 - 10:39 PM

#10

Someone correct me if i'm wrong but the kill switch could be a problem.


i already tested that. did basically what the manual said it should. when not being pressed, there was no continuity. when pressed, it would read resistance most of the time. from that, i can figure that if anything, the kill switch would be malfunctioning and letting it run instead of shutting it off





Related Content

Forums
Photo

are 2000 -2003 yz 125 cylinders then same? by dawson1120


Dirt Bike   Make / Model Specific   Yamaha   Yamaha 2-Stroke
  • 3 replies
Forums
Photo

06 yz125 won't start by 06yz125rider


Dirt Bike   Make / Model Specific   Yamaha   Yamaha 2-Stroke
  • 18 replies
Forums
Photo

Bottom End by wyattedwards250


Dirt Bike   Make / Model Specific   Yamaha   Yamaha 2-Stroke
  • 3 replies
Reviews

Yamaha YZ250 2013 by MXRider72


Yamaha YZ250 2013
  • 3 reviews
  • Last review by kb26racer
  • On July 10, 2014
Forums
Photo

bike for female rider? by rhii108


Dirt Bike   General Dirt Bike Forums   What bike should I buy?
  • 7 replies
 
x

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

RegisterSign InClose
If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.