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Discussion Starter #1
Hey guys, newbie here to the forum and absolutely a newbie when it comes to motorcycle builds.

I picked up a barn find 76 500T for $250. It didn't run. No carburetors and no battery. I installed a new battery and a few things don't work, but above all, there's no spark when i use the kick start.

I checked the spark plugs and they were foul and I bought a multimeter and the ignition coils read no reiststance in any Ohm setting. So obviously i need new coils and plugs.

My question is, however, what are the other things i should check/where do i find them on the bike/how do i test them. I'm going to order new parts but I want to hold off until I can compile a list of things to buy all at once and make a weekend or two out of it.

I Aorreciate the help!

I also don't have a Clymer manual yet and when it comes to electrical, I'm dyslexic so trying to make sense of a wiring diagram is at the same level of torture to me as waterboarding :D
 

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Sensei
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Infinite resistance in both the windings?....Are you reading Black/white wire to either Yellow or Blue?....There SHOULD be NO continuity to ground EXCEPT through the points, which you should have disconnected to test the coils......
Perhaps a re-test would help.....Phone me while you are at the bike, meter in hand.....540-525-5199.....Steve

P.S. a Factory service manual is infinitely preferable to any other.......PDF copies are available here through some member's generosity...
 

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Sensei
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Yes, all good EXCEPT, IF you have just a bad plug cap you'll get a bad coil reading as well...The coil MAY be good.....Phone.....

Caps are under $6....Coils are $50+
 

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Sensei
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Nope.....You are reading through BOTH coils' primary windings...... You SHOULD be reading from either Yellow OR Blue to Black/white.... So just to average (may not be absolutely correct, but) that approximates each coil at 4.75 Ohms....Right in the acceptable range.....

Next, you need to unscrew the plug caps (boots) and measure from Black/white to the end of the spark plug lead......Post those results....(10K to 15K ish is normal).
Then read the individual caps....Should be ~5K Ohms range each.....

Then verify NO CONTINUITY from UNPLUGGED coil end of both/either Black/white wire to coil bracket and sandwiched steel core bars (grounds)
 

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Discussion Starter #10
Nope.....You are reading through BOTH coils' primary windings...... You SHOULD be reading from either Yellow OR Blue to Black/white.... So just to average (may not be absolutely correct, but) that approximates each coil at 4.75 Ohms....Right in the acceptable range.....

Next, you need to unscrew the plug caps (boots) and measure from Black/white to the end of the spark plug lead......Post those results.....
Then read the individual caps....Shoud be ~5K Ohms range each.....
So, Just for clarity, I need to pull both little plugs out and read with my meter? So i basically read double...
 

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Sensei
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200 Ohm for primarys...read Black/white to yellow then Black/white to Blue......

20K scale for secondaries.....Read Black/white to plug end (without cap/boot)......

Read Black/white to core and should show infinite resistance "i"... Zero or any numerical reading here is bad.....
 

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Discussion Starter #12
. --------- Blue(S)-----
----Yellow(M)------=
. ------yellow (S)-------


. ------ Blue(S)-------
-----Blue(M)-------=
. -------yellow(S)------

So I unplug either blue/yellow (S) and measure either Blue or yellow (M)

Trying to visualize this through text

Edit: Of course this screws my format up...
 

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Sensei
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Coil test when you get them off.......You'll need the new "boots/caps" first.....

 

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Sensei
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It would take TWO of them wired in parallel to equal the original Ampere/Hr rating.....Pretty expensive.....
Plus you still have the re-charging limitations with Lithium batteries that require rectifier and regulator changes......
 

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Discussion Starter #17
So i had a little time tonight and i opened up the right hand controls and disconnected the other wires from the light switch the guy jerry-rigged as a kill switch and found out that the housing has nearly none of the brackets and is hollow/useless. There was one clip inside but the screw was stripped. Could this be causing the arcing that was resulting in my loss of voltage?

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Discussion Starter #18
New kill switch, new spark plugs, new boots, battery is fully charged. I press the starter button and the lights dim/shut off slightly but the starter motor won't turn. I kick it and no spark.

Next step, check the points?
 

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Points. Always check the points.
 

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Discussion Starter #20
Points. Always check the points.
Finally got the plate off with an impact drill and it's literally missing pieces. Like someone one day decided to fix it, forgot, and just closed it back up :(

I guess the next question is, go and order and electronic starter motor instead?
 
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