starting issues

6 replies to this topic
  • ZX10Rsilver

Posted March 16, 2010 - 11:20 AM


i have a 2002 yamaha yzf426 but its such a pain to start even impossible after its been cleaned, its seems to have a weak spark about one in three kicks gives it a good spark. My friend also has the same bike but a year older and we checked his spark and it much stronger and starts almost every time on second kick, heres what we,ve checked:
coil changed it over for his one still same
CDI changed it over for his one still same
wiring loom changed it over for his one same thing
magneto and pick up (this looked ok but on the pick ups inside the seemed to have been scratch by some thing so smoothed them back down) still same thing.
Can anyone help as were out of ideas?

  • DeeCee

Posted March 16, 2010 - 05:57 PM


Did you try changing the spark plug cap as well ?

If not give this a try.

  • tek_01

Posted March 16, 2010 - 10:27 PM


Do they have the same size jets? how are the valve clearances?
alot of variables

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  • grayracer513

Posted March 17, 2010 - 06:37 AM


In your process of trying known good components, you've eliminated everything except the wiring itself and the stator.

One thing that is frequently overlooked is the effect that the layer of metallic sludge that builds up on the inside of the flywheel has on the strength of the magnetic field used to generate electricity. Be sure that's cleaned out.

  • ZX10Rsilver

Posted March 17, 2010 - 09:49 AM


yEs I'll take a look but would the expelling of gases have Anything to do with a spark

  • grayracer513

Posted March 17, 2010 - 10:08 AM


...would the expelling of gases have Anything to do with a spark

No, that's usually the result of undigested starches.

What are you talking about?

  • ZX10Rsilver

Posted March 18, 2010 - 09:21 AM


valve clearances why would this change the spark, any way check magneto it nice and clean still same

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