If you need too fix your old cb400a cdi....heres what worked  for mine
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  1)replace capacitor 
www.mouser.com/Search/ProductDetail.aspx?qs=pnOZNUfuKbHY1Dnufbt69g%3d%3d
 Manufacturer Part #: DME4W1P5K-F 
Mouser Part #: 5989-400V1.5-F 
Manufacturer: Cornell Dubilier 
Description: Polyester Film Capacitors DME 400V1.5 
 


  2)replace old scr 3 prong chip labeled 5p4m with this 
http://www.mouser.com/Search/ProductDetail.aspx?qs=JJML70Qc14u1Y7KSFl6
H9Q%3d%3d 
   otherwise called..  Manufacturer Part #: S4008R 
Mouser Part #: 576-S4008R 
Manufacturer: Littelfuse 
Description: TVS SCR's S4008R 
 
 both parts only cost about 2bucks each.
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 The haredest thing about this repair is totally removing metal cdi housing.

 Too do this...have a metal worker grind all for corners then peel and bend
 housing off....then throw away. you make a plastic one later.
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 Once removed you need too soak the whole cdi but not elec 
wire harness-into the strongest jelly type paint stripper from walmart ($6).
 Let soak in small metal can and cover with tin foil  maybe a few hours 
until you melt off enough crap to start too see a green or yellow capacitor.
 (THIS CAN SHOCK YOU-dont touch with out insulated tools). If you can,
see if there are written readable numbers on this part.
If there is, write them down and replace with same uf rating. I choose 1.5uf 400v film capacitor
 because i saw an old honda cx500 twin that used 1.5uf.
 Return unit too paint stripper for up to 3 days. 
This should melt all compounds off exposing a clean circuit board. 
Wash with garden hose pressure spray , then let dry completely.
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 IF ANY ONE FINDS OUT WHICH CAPACITOR WAS USED ORIGINALLY,PLEASE LET ME KNOW
1UF 1.5UF 2UF OR 2.2UF AND WHAT VOLTAGE RATING? 
EMAIL ME    SJSARTWORK@CHARTER.NET
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 Now remove old capacitor(shaped like 2 aaa batteries side by side).
SNIP THE LEADS CONNECTED TO THE CAPACITOR AS CLOSE TO THE CAPACITOR AS 
POSSIBLE. You'll need too rough these 2 prongs up with sandpaper so you 
can solder to them the new capacitor. It doesnt matter which end you solder
 on where.It's non polarized.
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 Next remove old 5p4m scr chip. Should be a rectangle green chip encased in
 a clear plastic housing. Its about the size of a dime. Clip the chip out 
with snippers, leaving the 3 prongs in place. NOTE WHICH DIRECTION THE CHIP
 IS IN PLACE SO YOU CAN SOLDER THE NEW ONE IN THE SAME. Too remove the prongs
 , heat up the prongs with solder iron. While hot ,pull one out at a time 
with pliers. If you know how to desolder stuff , thats is obviously the 
correct thing to do here. Once the prongs are out just stick the tip of your
 solder iron in or on each prong hole and heat up a-lot then remove iron 
quickly. That should clear the little holes.....
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 Next position the new chip in like the last one and solder in place.
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 Look at your circuit board and wire connections. If you see any cracks in 
the solders or circuit paths,resolder up those cracks. Clean any corrosion 
that looks obvious. YOUR ALMOST DONE!!!
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 Its time too test the unit...
 First wrap circuit board completely in electric tape. Doesnt need too be 
tight,you'll remove that later. It's just to prevent shocks to you...
 Plug everything into bike as it should. Start and run bike. It should run
 like a charm. If so, remove it from bike and BE CAREFUL...THE CAPACITOR IS
 NOW CHARGED!!! Too remove charge...pull off tape and use insulated 
screwdriver to ground the 2 capacitor  leads together a few times. 
If you dont want to do this, just be careful to not touch any part of the
 actual circuit board or capacitor.
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 Lastly you need too make or find a durable plastic housing about the 
original size. You should fill half the container with a non conductive 
silicon or potting compound. Settle cdi into this, then fill the other side 
of plastic container so the cdi should be totally encased in this silicon.
 You might need too let dry for up to a week(the rubber helps protect from 
(weather,vibration,and heat). Just be patient, cause you'll have a working 
cdi for real cheap and will have saved possible hundreds.  

good luck
god bless 
and be careful
email me and let me know if this helped you sjsartwork@charter.net
