1986 Honda CR500 Coil Resistance

I am in the process of rebuilding a 1986 CR500.  I have it mostly back together and trying to get it started.  It has been sitting for a long time.  It has good compress and clean gas. 


It has what I consider weak spank on the plug.  I measured the primary coil resistance and it's .5 ohms.  The manual I have calls for a spec range from .2-.4 ohms.  Then I see another value online of .2 ohms.  Which is correct?


Could this high resistance be the root cause for my weak spark?

Before getting too excited about whether the coil is bad or not, pull the coil off the frame and clean up the coil and the frame.  You could just have a bad ground is all.  Also check the wires and connections and clean or replace if neccesary.  Then if it still has weak spark, a coil for that bike is only like 20 bucks. 

Edited by TUK101

end the pain now buy a cr250 ignition for that bike - 92 - 01 install easily, easy starting and easy maneuvering will be yours for doing this. second best ever thing for that bike is install a pwk carb. third best is a compression relese head because it makes them feel like your kicking a 125 and it will save your old cases from breaking,

Should I replace the entire ignition system.  That is- the startor, rotor, pulse box and coil. 


My plan is to keep this bike for a long time.  I want it to be easy to start and easy to maintain.


Do you also have a link for the ignition system?



complete ignition system, grind the colar out of the stator backing plate then stuff an oring in it to help center it then tighten it down alighning timing mark, simple? if you need a decomp head I have a few let me know and we'll work something out.

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